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Miloch D, Cecchetto NR, Lescano JN, Leynaud GC, Perotti MG. Is thermal sensitivity affected by predation risk? A case study in tadpoles from ephemeral environments. J Exp Zool A Ecol Integr Physiol 2024; 341:400-409. [PMID: 38356256 DOI: 10.1002/jez.2793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 01/29/2024] [Accepted: 02/01/2024] [Indexed: 02/16/2024]
Abstract
Changes in environmental temperature may induce variations in thermal tolerance and sensitivity in ectotherm organisms. These variations generate plastic responses that can be analyzed by examining their Thermal Performance Curves (TPCs). Additionally, some performance traits, like locomotion, could be affected by other factors such as biological interactions (e.g., predator-prey interaction). Here, we evaluate if the risk of predation modifies TPCs in Mendoza four-eyed frog (Pleurodema nebulosum, Burmeister, 1861) and Guayapa's four-eyed frog (Pleurodema guayapae, Barrio, 1964), two amphibian species that occur in ephemeral ponds in arid environments. We measured thermal tolerances and maximum swimming velocity at six different temperatures in tadpoles under three situations: control, exposure to predator chemical cues, and exposure to conspecific alarm cues. TPCs were fitted using General Additive Mixed Models. We found that curves of tadpoles at risk of predation differed from those of control mainly in thermal sensitivity parameters. Our work confirms the importance of biotic interactions have in thermal physiology.
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Affiliation(s)
- Daniela Miloch
- Facultad de Ciencias Exactas, Físicas, y Naturales, Centro de Zoología Aplicada, Universidad Nacional de Córdoba, Córdoba, Argentina
- Instituto de Diversidad y Ecología Animal, Consejo Nacional de Investigaciones Científicas y Técnicas, Córdoba, Argentina
| | - Nicolas R Cecchetto
- Instituto de Investigaciones en Biodiversidad y Medio Ambiente, Consejo Nacional de Investigaciones Científicas y Técnicas, Bariloche, Río Negro, Argentina
| | - Julián N Lescano
- Facultad de Ciencias Exactas, Físicas, y Naturales, Centro de Zoología Aplicada, Universidad Nacional de Córdoba, Córdoba, Argentina
- Instituto de Diversidad y Ecología Animal, Consejo Nacional de Investigaciones Científicas y Técnicas, Córdoba, Argentina
| | - Gerardo C Leynaud
- Facultad de Ciencias Exactas, Físicas, y Naturales, Centro de Zoología Aplicada, Universidad Nacional de Córdoba, Córdoba, Argentina
- Instituto de Diversidad y Ecología Animal, Consejo Nacional de Investigaciones Científicas y Técnicas, Córdoba, Argentina
| | - María Gabriela Perotti
- Instituto de Investigaciones en Biodiversidad y Medio Ambiente, Consejo Nacional de Investigaciones Científicas y Técnicas, Bariloche, Río Negro, Argentina
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Huggenberger S, Walkowiak W. Evolution of air-borne vocalization: Insights from neural studies in the archeobatrachian species Bombina orientalis. J Comp Neurol 2024; 532:e25601. [PMID: 38450738 DOI: 10.1002/cne.25601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 01/30/2024] [Accepted: 02/23/2024] [Indexed: 03/08/2024]
Abstract
Vocalization of tetrapods evolved as an air-driven mechanism. Thus, it is conceivable that the underlaying neural network might have evolved from more ancient respiratory circuits and be made up of homologous components that generate breathing rhythms across vertebrates. In this context, the extant species of stem anurans provide an opportunity to analyze the connection of the neural circuits of lung ventilation and vocalization. Here, we analyzed the fictive lung ventilation and vocalization behavior of isolated brains of the Chinese fire-bellied toad Bombina orientalis during their mating season by nerve root recordings. We discovered significant differences in durations of activation of male brains after stimulation of the statoacoustic nerve or vocalization-relevant forebrain structures in comparison to female brains. The increased durations of motor nerve activities in male brains can be interpreted as fictive calling, as male's advertisement calls in vivo had the same general pattern compared to lung ventilation, but longer duration periods. Female brains react to the corresponding stimulations with the same shorter activity pattern that occurred spontaneously in both female and male brains and thus can be interpreted as fictive lung ventilations. These results support the hypothesis that vocal circuits evolved from ancient respiration networks in the anuran caudal hindbrain. Moreover, we could show that the terrestrial stem archeobatrachian Bombina spec. is an appropriate model to study the function and evolution of the shared network of lung ventilation and vocal generation.
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Affiliation(s)
- Stefan Huggenberger
- Institute of Anatomy and Clinical Morphology, Witten/Herdecke University, Witten, Germany
- Institute for Zoology, University of Cologne, Cologne, Germany
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da Silva ICO, Soares P, Malta L, Paiva F, Ferreira VL, de Oliveira CE, Tavares LER. New insights into a poorly known parasite, Dero lutzi (Oligochaeta: Naididae), associated with tree frogs of the genus Scinax: morphological evaluation and genotypic data. Rev Bras Parasitol Vet 2024; 33:e015323. [PMID: 38198362 PMCID: PMC10782506 DOI: 10.1590/s1984-29612024005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Accepted: 12/05/2023] [Indexed: 01/12/2024]
Abstract
The oligochaete Dero lutzi follows a life strategy that alternates between free-living periods in aquatic environments and endoparasitic phases. Most occurrences of D. lutzi in anurans are reported in species with arboreal habits, with studies limited to the recording of the oligochaete's presence in the host. Our study recovered specimens of D. lutzi from the tree frogs Scinax fuscovarius and Scinax. nasicus. We performed a morphological assessment of the parasite using light microscopy, for the first time, scanning electron microscopy. Molecular characterization of D. lutzi was carried out using the mitochondrial gene 16S rRNA and the nuclear gene 28S rRNA. Additionally, a phylogenetic tree was constructed to assess the species´position in relation to other group members. In our results, we confirmed the phenotypic morphological characteristics of the endoparasitic phase of D. lutzi. We also presented its phylogenetic position with other oligochaetes in the group, demonstrating the proximity between the endoparasite D. lutzi and the free-living oligochaete D. superterrenus.
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Affiliation(s)
- Isabela Caroline Oliveira da Silva
- Laboratório de Ciências Ambientais e Sustentabilidade Agropecuária, Universidade Católica Dom Bosco – UCDB, Campo Grande, MS, Brasil
- Laboratório de Parasitologia Animal, Instituto de Biociências, Universidade Federal de Mato Grosso do Sul – UFMS, Campo Grande, MS, Brasil
| | - Priscilla Soares
- Laboratório de Parasitologia Animal, Instituto de Biociências, Universidade Federal de Mato Grosso do Sul – UFMS, Campo Grande, MS, Brasil
- Laboratório de Pesquisa em Herpetologia, Instituto de Biociências, Universidade Federal de Mato Grosso do Sul – UFMS, Campo Grande, MS, Brasil
| | - Lennon Malta
- Laboratório de Parasitologia Animal, Instituto de Biociências, Universidade Federal de Mato Grosso do Sul – UFMS, Campo Grande, MS, Brasil
| | - Fernando Paiva
- Laboratório de Parasitologia Animal, Instituto de Biociências, Universidade Federal de Mato Grosso do Sul – UFMS, Campo Grande, MS, Brasil
| | - Vanda Lúcia Ferreira
- Laboratório de Pesquisa em Herpetologia, Instituto de Biociências, Universidade Federal de Mato Grosso do Sul – UFMS, Campo Grande, MS, Brasil
| | - Carina Elisei de Oliveira
- Laboratório de Ciências Ambientais e Sustentabilidade Agropecuária, Universidade Católica Dom Bosco – UCDB, Campo Grande, MS, Brasil
| | - Luiz Eduardo Roland Tavares
- Laboratório de Parasitologia Animal, Instituto de Biociências, Universidade Federal de Mato Grosso do Sul – UFMS, Campo Grande, MS, Brasil
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Das K, Rödel M, Stanley E, Srikanthan AN, Shanker K, Vijayakumar SP. Reed bamboos drive skull shape evolution in bush frogs of the Western Ghats, Peninsular India. Ecol Evol 2023; 13:e10493. [PMID: 37680959 PMCID: PMC10480065 DOI: 10.1002/ece3.10493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 08/15/2023] [Accepted: 08/21/2023] [Indexed: 09/09/2023] Open
Abstract
Reed bamboo is a major ecological and economic resource for many animals, including humans. Nonetheless, the influence of this plant's evolutionary role on the morphology of animal species remains unexplored. Here, we investigated the significance of bamboo habitats as ecological opportunities in shaping the skull morphology of bush frogs (Raorchestes) from the Western Ghats, Peninsular India. We applied a three-dimensional (3D) geometric morphometric approach to capture the skull shape of 55 species of bush frogs. We visualized the skull shape variables in phylomorphospace with principal component analysis and performed phylogenetic generalized least-squares analysis to assess the impact of cranial size (evolutionary allometry) and habitat (bamboo or non-bamboo) on cranial shape. We quantified the morphological disparity between bamboo and non-bamboo bush frogs' skull shape, and employed RRphylo, a phylogenetic ridge regression method, to access the evolutionary rate and rate shifts of skull shape change. The phylomorphospace delineated bamboo and non-bamboo bush frogs. While cranial shape exhibited a significant but smaller association with size, its association with habitat type was non-significant. We detected, however, significant differences in skull shape between the two frog groups, with bamboo frogs showing higher morphological disparity and a remarkable shift in the evolutionary rate of skull shape diversification. These findings underscore the role of reed bamboo in the evolution of skull shape in the radiation of frogs, endemic to the Western Ghats. We demonstrate that the association between the members of two distinct endemic clades (bamboo reeds and bamboo frogs) is the outcome of a deep-time ecological opportunity that dates back to the Miocene.
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Affiliation(s)
- Kalpana Das
- Museum für Naturkunde – Leibniz Institute for Evolution and Biodiversity ScienceBerlinGermany
| | - Mark‐Oliver Rödel
- Museum für Naturkunde – Leibniz Institute for Evolution and Biodiversity ScienceBerlinGermany
| | - Edward Stanley
- Department of Natural History, Florida Museum of Natural HistoryUniversity of FloridaGainesvilleFloridaUSA
| | - Achyuthan N. Srikanthan
- Centre for Ecological SciencesIndian Institute of ScienceBangaloreIndia
- Department of BiologyClark UniversityWorcesterMassachusettsUSA
| | - Kartik Shanker
- Centre for Ecological SciencesIndian Institute of ScienceBangaloreIndia
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Otero Y, Calatayud NE, Arcia ID, Mariscal D, Samaniego D, Rodríguez D, Rodríguez K, Guerrel J, Ibáñez R, Della Togna G. Recovery and Characterization of Spermatozoa in a Neotropical, Terrestrial, Direct-Developing Riparian Frog ( Craugastor evanesco) through Hormonal Stimulation. Animals (Basel) 2023; 13:2689. [PMID: 37684953 PMCID: PMC10486684 DOI: 10.3390/ani13172689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 08/19/2023] [Accepted: 08/19/2023] [Indexed: 09/10/2023] Open
Abstract
The Vanishing Rainfrog (Craugastor evanesco) is an endemic and critically endangered frog species of Panama. It is suspected that 90% of the population has disappeared from the wild. Frogs were collected from the wild and brought to a Captive Breeding Program; however, accomplishing regular reproductive events for this species has been difficult. The objective of this study was to determine the effect of hormonal stimulation on the production and quality of C. evanesco spermatozoa, aiming to develop an efficient and safe sperm collection protocol as a tool to help reproduce this endangered species. Mature males received intra-peritoneal injections with one of six hormone treatments, including des-Gly10, D-Ala6, Pro-NHEt9-GnRH-A, Amphiplex or hCG. Urine samples were collected at 10 different time points post-injection. Quality assessments included sperm concentration, percentage motility, percentage forward progressive motility (FPM), osmolality, pH and morphology analysis. Our results indicate that the optimal treatment for the collection of highly concentrated sperm samples of C. evanesco is 4 µg/gbw GnRH, followed by Amphiplex and 2 µg/gbw GnRH as sub-optimal treatments and finally, 6 µg/gbw GnRH and 5 and 10 IU/gbw hCG as non-optimal treatments. GnRH-A at 4 μg/gbw and Amphiplex stimulated the production of samples with the highest sperm concentrations and quality, despite Amphiplex producing lower percentages of intact acrosome and tail. In contrast, hCG concentrations were not reliable inducers of sperm production, consistently showing lower concentrations, higher percentages of sperm abnormalities and more acidic spermic urine than that induced by Amphiplex and GnRH-A. Morphological assessments revealed that C. evanesco spermatozoa have a filiform shape with a large acrosome on the anterior part of an elongated head, a small midpiece and a long tail with two filaments joined together by an undulating membrane.
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Affiliation(s)
- Yineska Otero
- Smithsonian Tropical Research Institute, Balboa, Ancón, Apartado 0843-03092, Panama; (Y.O.); (I.D.A.); (D.M.); (D.S.); (D.R.); (K.R.); (J.G.); (R.I.)
- Facultad de Medicina Veterinaria, Universidad de Panamá, Bella Vista, Apartado 3366, Panama
| | - Natalie E. Calatayud
- San Diego Zoo Wildlife Alliance, Beckman Center for Conservation Research, 15600 San Pasqual Valley Road, Escondido, CA 92025, USA;
| | - Igli D. Arcia
- Smithsonian Tropical Research Institute, Balboa, Ancón, Apartado 0843-03092, Panama; (Y.O.); (I.D.A.); (D.M.); (D.S.); (D.R.); (K.R.); (J.G.); (R.I.)
| | - Denise Mariscal
- Smithsonian Tropical Research Institute, Balboa, Ancón, Apartado 0843-03092, Panama; (Y.O.); (I.D.A.); (D.M.); (D.S.); (D.R.); (K.R.); (J.G.); (R.I.)
- Facultad de Medicina Veterinaria, Universidad de Panamá, Bella Vista, Apartado 3366, Panama
| | - Diego Samaniego
- Smithsonian Tropical Research Institute, Balboa, Ancón, Apartado 0843-03092, Panama; (Y.O.); (I.D.A.); (D.M.); (D.S.); (D.R.); (K.R.); (J.G.); (R.I.)
- Facultad de Medicina Veterinaria, Universidad de Panamá, Bella Vista, Apartado 3366, Panama
| | - Dionel Rodríguez
- Smithsonian Tropical Research Institute, Balboa, Ancón, Apartado 0843-03092, Panama; (Y.O.); (I.D.A.); (D.M.); (D.S.); (D.R.); (K.R.); (J.G.); (R.I.)
- Facultad de Ciencias Naturales, Exactas y Tecnología, Escuela de Biología, Universidad de Panamá, Bella Vista, Apartado 3366, Panama
| | - Karina Rodríguez
- Smithsonian Tropical Research Institute, Balboa, Ancón, Apartado 0843-03092, Panama; (Y.O.); (I.D.A.); (D.M.); (D.S.); (D.R.); (K.R.); (J.G.); (R.I.)
- Facultad de Ciencias Naturales, Exactas y Tecnología, Escuela de Biología, Universidad de Panamá, Bella Vista, Apartado 3366, Panama
| | - Jorge Guerrel
- Smithsonian Tropical Research Institute, Balboa, Ancón, Apartado 0843-03092, Panama; (Y.O.); (I.D.A.); (D.M.); (D.S.); (D.R.); (K.R.); (J.G.); (R.I.)
| | - Roberto Ibáñez
- Smithsonian Tropical Research Institute, Balboa, Ancón, Apartado 0843-03092, Panama; (Y.O.); (I.D.A.); (D.M.); (D.S.); (D.R.); (K.R.); (J.G.); (R.I.)
- Facultad de Ciencias Naturales, Exactas y Tecnología, Escuela de Biología, Universidad de Panamá, Bella Vista, Apartado 3366, Panama
| | - Gina Della Togna
- Smithsonian Tropical Research Institute, Balboa, Ancón, Apartado 0843-03092, Panama; (Y.O.); (I.D.A.); (D.M.); (D.S.); (D.R.); (K.R.); (J.G.); (R.I.)
- The Amphibian Survival Alliance, Apartado 0830-00689, Panama
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Piazza YG, Czuchlej SC, Gómez ML, Meijide FJ. Gonadal morphogenesis in the South American toad Rhinella Arenarum ( Anura, Bufonidae) unveils an extremely delayed rate of sex differentiation. J Morphol 2023; 284:e21611. [PMID: 37458081 DOI: 10.1002/jmor.21611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 05/26/2023] [Accepted: 06/06/2023] [Indexed: 07/18/2023]
Abstract
Among anurans, Bufonids are recognized for their retarded sex differentiation. However, few studies have addressed gonadal morphogenesis in this family. Here, we analyzed the early gonadogenesis in laboratory-reared Rhinella arenarum. Few germ cells were identified in the genital ridge at Gosner stage 26. At metamorphosis, somatic cells and germ cells were observed in the outer region of the undifferentiated gonad, whereas the central region was occupied by stromal tissue. A cortico-medullary organization was first recognized on Day 7 postmetamorphosis. The cortex was composed of germ cells and encompassing epithelial cells, whereas the medulla contained cells presumptively derived from the coelomic epithelium. Medullary somatic cells formed metameric knots along the length of the undifferentiated gonad. Consequently, a series of 12-14 gonomeres became recognizable externally. The first sign of ovarian differentiation was observed on Day 15 postmetamorphosis, when a cavity was formed within each gonomere. In contrast, testes were recognized by a uniform distribution of germ cells and intermingled somatic cells, as the division into cortex and medulla was lost. By Day 50 postmetamorphosis, the gonadal metameric organization was still apparent both in the ovaries and testes. Follicles containing diplotene oocytes were observed within the ovary. In the testis, an incipient lobular architecture was recognized without initiation of meiosis within the seminiferous cords. These observations reveal an extremely delayed gonadal development in R. arenarum, not reported previously for other anuran species. In addition, the late differentiation of the gonads contrasted with the early appearance of follicles in the Bidder's organ. Lastly, we observed that delayed metamorphs exhibited an undifferentiated gonad, demonstrating that gonadogenesis in this species is more dependent on somatic development than on age.
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Affiliation(s)
- Yanina G Piazza
- Laboratorio de Ecotoxicología Acuática, DBBE and IBBEA-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Ciudad Autónoma de Buenos Aires, Argentina
| | - Silvia C Czuchlej
- Laboratorio de Ecotoxicología Acuática, DBBE and IBBEA-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Ciudad Autónoma de Buenos Aires, Argentina
| | - María L Gómez
- Instituto de Bio y Geociencias del NOA, CONICET, Centro Científico Tecnológico-Salta, Salta, Argentina
| | - Fernando J Meijide
- Laboratorio de Ecotoxicología Acuática, DBBE and IBBEA-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Ciudad Autónoma de Buenos Aires, Argentina
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Kim YI, Chuang MF, Borzée A, Kwon S, Jang Y. Latitude-Induced and Behaviorally Thermoregulated Variations in Upper Thermal Tolerance of Two Anuran Species. Biology (Basel) 2022; 11:1506. [PMID: 36290410 DOI: 10.3390/biology11101506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 10/02/2022] [Accepted: 10/11/2022] [Indexed: 11/17/2022]
Abstract
Although thermal tolerance along geographical gradients gives an insight into species' response to climate change, current studies on thermal tolerance are strongly skewed towards global-scale patterns. As a result, intraspecific variations are often assumed to be constant, despite a lack of evidence. To understand population-specific responses to thermal stress, we investigated the presence of intraspecific variations in the critical thermal maximum (CTmax) of tadpoles in two anuran species, Rana uenoi and Bufo sachalinensis. The study was conducted across a five-degree latitudinal gradient in the Republic of Korea. We exposed the tadpoles to increasing temperatures and recorded the CTmax for 270 R. uenoi individuals from 11 sites, collected in rice paddies, and for 240 B. sachalinensis individuals from ten sites, collected in reservoirs. We also recorded the swimming performance and behavior of the tadpoles when placed in an experimental apparatus during CTmax measurements. We then used linear regressions to determine the relationship between abiotic factors and CTmax. In R. uenoi, we found a positive relationship between latitude and CTmax, but the tadpoles did not display specific thermoregulatory behaviors. In B. sachalinensis, none of the abiotic factors such as climate and geographic coordinates were related to CTmax, but we detected a tendency to swim close to the water surface when water temperature was increasing. For R. uenoi, we tentatively relate the CTmax variability across the latitudinal gradient to a physiological adaptive response associated with habitat characteristics that are assumed to be fluctuating, as the species inhabits small water bodies prone to drying out. In the case of B. sachalinensis, the behavior observed may be linked to oxygen depletion and thermoregulation, as it may buffer temperature changes in the absence of physiological adjustment. These findings suggest that intra-specific variations in CTmax are greater than generally accounted for, and thermal conditions of natural environments are important for understanding thermal tolerance in ectothermic species. Our results highlight that species' specific responses to climate warmings need to be studied to better protect species against climate change.
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Gorbsky GJ, Daum JR, Sapkota H, Summala K, Yoshida H, Georgescu C, Wren JD, Peshkin L, Horb ME. Developing immortal cell lines from Xenopus embryos , four novel cell lines derived from Xenopus tropicalis. Open Biol 2022; 12:220089. [PMID: 35857907 PMCID: PMC9256088 DOI: 10.1098/rsob.220089] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The diploid anuran Xenopus tropicalis has emerged as a key research model in cell and developmental biology. To enhance the usefulness of this species, we developed methods for generating immortal cell lines from Nigerian strain (NXR_1018, RRID:SCR_013731) X. tropicalis embryos. We generated 14 cell lines that were propagated for several months. We selected four morphologically distinct lines, XTN-6, XTN-8, XTN-10 and XTN-12 for further characterization. Karyotype analysis revealed that three of the lines, XTN-8, XTN-10 and XTN-12 were primarily diploid. XTN-6 cultures showed a consistent mixed population of diploid cells, cells with chromosome 8 trisomy, and cells containing a tetraploid content of chromosomes. The lines were propagated using conventional culture methods as adherent cultures at 30°C in a simple, diluted L-15 medium containing fetal bovine serum without use of a high CO2 incubator. Transcriptome analysis indicated that the four lines were distinct lineages. These methods will be useful in the generation of cell lines from normal and mutant strains of X. tropicalis as well as other species of Xenopus.
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Affiliation(s)
- Gary J. Gorbsky
- Cell Cycle and Cancer Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA,Depatment of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - John R. Daum
- Cell Cycle and Cancer Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Hem Sapkota
- Cell Cycle and Cancer Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Katja Summala
- Cell Cycle and Cancer Biology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Hitoshi Yoshida
- National Xenopus Resource and Eugene Bell Center for Regeneration Biology and Tissue Engineering, Marine Biological Laboratory, Woods Hole, MA, USA
| | - Constantin Georgescu
- Genes and Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Jonathan D. Wren
- Genes and Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, USA
| | - Leonid Peshkin
- National Xenopus Resource and Eugene Bell Center for Regeneration Biology and Tissue Engineering, Marine Biological Laboratory, Woods Hole, MA, USA,Department of Systems Biology, Harvard Medical School, Boston, MA, USA
| | - Marko E. Horb
- National Xenopus Resource and Eugene Bell Center for Regeneration Biology and Tissue Engineering, Marine Biological Laboratory, Woods Hole, MA, USA
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Paitz RT, Dugas MB. Steroid levels in frog eggs: Manipulations, developmental changes, and implications for maternal steroid effects. J Exp Zool Pt A 2022; 337:293-302. [PMID: 34905660 DOI: 10.1002/jez.2566] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 11/21/2021] [Accepted: 11/23/2021] [Indexed: 06/14/2023]
Abstract
Exposure to maternally derived steroids during embryonic development can elicit phenotypic effects in the resulting offspring. Studies of maternal steroid effects, especially rich in mammals and birds, have offered exciting insights into the evolution of maternal effects in vertebrates. To extend this literature, we quantified levels of steroids in the eggs of four neotropical dendrobatid frogs that lay terrestrial clutches, a reproductive strategy that has evolved multiple times in amphibians. Building on our observational results, we then manipulated levels of pregnenolone and progesterone in eggs of one species and examined how this affected steroid levels during development. Eggs of all four species had detectable steroids levels, with progestogens being more abundant than androgens and glucocorticoids. Estrogens could not be detected. Immersion of frog eggs in a solution containing pregnenolone and progesterone resulted in elevated levels of both steroids early in development, but levels declined and were similar to those in unmanipulated eggs by the end of development. Treated eggs also exhibited a transient increase in levels of steroids that can be produced from pregnenolone and progesterone. Overall, our findings demonstrate that frog eggs contain steroids similar to what has been observed in other egg-laying vertebrates. During development, steroid levels are dynamic, further suggesting developing embryos regulate exposure to maternal steroids. These results set the stage for investigating the causes and consequences of maternal steroid effects in frogs.
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Affiliation(s)
- Ryan T Paitz
- School of Biological Sciences, Illinois State University, Normal, Illinois, USA
| | - Matthew B Dugas
- School of Biological Sciences, Illinois State University, Normal, Illinois, USA
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Almeida-Gomes M, Gotelli NJ, Rocha CFD, Vieira MV, Prevedello JA. Random placement models explain species richness and dissimilarity of frog assemblages within Atlantic Forest fragments. J Anim Ecol 2022; 91:618-629. [PMID: 35007336 DOI: 10.1111/1365-2656.13660] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 12/21/2021] [Indexed: 11/28/2022]
Abstract
Understanding the effects of random versus niche-based processes on biodiversity patterns is a central theme in ecology, and an important tool for predicting effects of habitat loss and fragmentation on biodiversity. We investigated the predictive power of random processes to explain species richness and species dissimilarity of amphibian assemblages in a fragmented tropical landscape of the Atlantic Forest of South America. We analyzed a large database of amphibian abundance and occupancy, sampled in 21 forest fragments ranging in size from 1.9 to 619 ha. We compared observed species richness and species dissimilarity with the outcomes of two null (random placement) models: 1- the traditional Coleman's area-based model and 2- an abundance-based model (based on the number of individuals observed in each fragment). We applied these models for all species combined, and separately for forest-dependent and habitat-generalist species. The abundance-based model fitted the observed species richness data better than the area-based model for all species, forest-dependent species, and generalist species. The area-based and the abundance-based models were also able to significantly explain species dissimilarity for all species and for generalists, but not for forest dependent species. The traditional area-based model assigned too many individuals to large fragments, thus failing to accurately explain species richness within patches across the landscape. Although niche-based processes may be important to structuring the regional pool of species in fragmented landscapes, our results suggest that part of the variation in species richness and species dissimilarity can be successfully explained by random placement models, especially for generalist species. Evaluating which factors cause variation in the number of individuals among patches should be a focus in future studies aiming to understand biodiversity patterns in fragmented landscapes.
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Affiliation(s)
- Mauricio Almeida-Gomes
- Instituto de Biociências, Universidade Federal de Mato Grosso do Sul, Campo Grande, Brazil
| | | | | | - Marcus Vinícius Vieira
- Laboratório de Vertebrados, Departamento de Ecologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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11
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Hutter CR, Cobb KA, Portik DM, Travers SL, Wood PL, Brown RM. FrogCap: A modular sequence capture probe-set for phylogenomics and population genetics for all frogs, assessed across multiple phylogenetic scales. Mol Ecol Resour 2021; 22:1100-1119. [PMID: 34569723 DOI: 10.1111/1755-0998.13517] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 09/08/2021] [Accepted: 09/14/2021] [Indexed: 12/01/2022]
Abstract
Despite the prevalence of high-throughput sequencing in phylogenetics, many relationships remain difficult to resolve because of conflicting signal among genomic regions. Selection of different types of molecular markers from different genomic regions is required to overcome these challenges. For evolutionary studies in frogs, we introduce the publicly available FrogCap suite of genomic resources, which is a large collection of ~15,000 markers that unifies previous genetic sequencing efforts. FrogCap is designed to be modular, such that subsets of markers and SNPs can be selected based on the desired phylogenetic scale. FrogCap uses a variety of marker types that include exons and introns, ultraconserved elements, and previously sequenced Sanger markers, which span up to 10,000 bp in alignment lengths; in addition, we demonstrate potential for SNP-based analyses. We tested FrogCap using 121 samples distributed across five phylogenetic scales, comparing probes designed using a consensus- or exemplar genome-based approach. Using the consensus design is more resilient to issues with sensitivity, specificity, and missing data than picking an exemplar genome sequence. We also tested the impact of different bait kit sizes (20,020 vs. 40,040) on depth of coverage and found triple the depth for the 20,020 bait kit. We observed sequence capture success (i.e., missing data, sequenced markers/bases, marker length, and informative sites) across phylogenetic scales. The incorporation of different marker types is effective for deep phylogenetic relationships and shallow population genetics studies. Having demonstrated FrogCap's utility and modularity, we conclude that these new resources are efficacious for high-throughput sequencing projects across variable timescales.
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Affiliation(s)
- Carl R Hutter
- Biodiversity Institute and Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, Kansas, USA
| | - Kerry A Cobb
- Biodiversity Institute and Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, Kansas, USA
| | - Daniel M Portik
- California Academy of Sciences, San Francisco, California, USA
| | - Scott L Travers
- Biodiversity Institute and Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, Kansas, USA.,Department of Biological Sciences, Rutgers University-Newark, Newark, New Jersey, USA
| | - Perry L Wood
- Biodiversity Institute and Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, Kansas, USA
| | - Rafe M Brown
- Biodiversity Institute and Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, Kansas, USA
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12
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Reuben PL, Touchon JC. Nothing as it seems: behavioural plasticity appears correlated with morphology and colour, but is not in a Neotropical tadpole. Proc Biol Sci 2021; 288:20210246. [PMID: 33849314 PMCID: PMC8059526 DOI: 10.1098/rspb.2021.0246] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 03/19/2021] [Indexed: 12/20/2022] Open
Abstract
In response to environmental stressors, organisms often demonstrate flexible responses in morphology, life history or behaviour. However, it is currently unclear if such plastic responses are coordinated or operate independently of one another. In vertebrates, this may partly result from studies examining population- or species-level mean responses, as opposed to finer grained analyses of individuals or families. We measured predator-specific morphological and coloration plasticity in 42 families of tadpoles of the treefrog Dendropsophus ebraccatus and behavioural plasticity from 18 of these families, allowing us to examine the correlation between three predator-induced plastic responses. For all three plastic responses, tadpoles showed strong opposing responses to each of two predators, providing the appearance of covariation in plasticity. However, the examination of individual families revealed a strong correlation between morphological and coloration plasticity, but no correlations between either morphology or colour and behavioural plasticity. Thus, our analysis shows that some aspects of the plastic phenotype develop together while others function independently. This highlights the importance of examining individual- and family-level variation for understanding the adaptive significance of developmental plasticity, which is crucial for a holistic appreciation of phenotypic plasticity and its importance in ecology and evolution.
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Affiliation(s)
- Phoebe L. Reuben
- Department of Biology, Vassar College, 124 Raymond Avenue, Poughkeepsie, NY 12604, USA
| | - Justin C. Touchon
- Department of Biology, Vassar College, 124 Raymond Avenue, Poughkeepsie, NY 12604, USA
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13
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Kunisch S, Blüml V, Schwaha T, Beisser CJ, Handschuh S, Lemell P. Digital dissection of the head of the frogs Calyptocephalella gayi and Leptodactylus pentadactylus with emphasis on the feeding apparatus. J Anat 2021; 239:391-404. [PMID: 33713453 PMCID: PMC8273601 DOI: 10.1111/joa.13426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 02/21/2021] [Accepted: 02/22/2021] [Indexed: 11/26/2022] Open
Abstract
Micro‐computed tomography (microCT) of small animals has led to a more detailed and more accurate three‐dimensional (3D) view on different anatomical structures in the last years. Here, we present the cranial anatomy of two frog species providing descriptions of bone structures and soft tissues of the feeding apparatus with comments to possible relations to habitat and feeding ecology. Calyptocephalella gayi, known for its aquatic lifestyle, is not restricted to aquatic feeding but also feeds terrestrially using lingual prehension. This called for a detailed investigation of the morphology of its feeding apparatus and a comparison to a fully terrestrial species that is known to feed by lingual prehension such as Leptodactylus pentadactylus. These two frog species are of similar size, feed on similar diet but within different main habitats. MicroCT scans of both species were conducted in order to reconstruct the complete anatomical condition of the whole feeding apparatus for the first time. Differences in this regard are evident in the tongue musculature, which in L. pentadactylus is more massively built and with a broader interdigitating area of the two main muscles, the protractor musculus genioglossus and the retractor musculus hyoglossus. In contrast, the hyoid retractor (m. sternohyoideus) is more massive in the aquatic species C. gayi. Moreover, due to the different skull morphology, the origins of two of the five musculi adductores vary between the species. This study brings new insights into the relation of the anatomy of the feeding apparatus to the preferred feeding method via 3D imaging techniques. Contrary to the terrestrially feeding L. pentadactylus, the skeletal and muscular adaptations of the aquatic species C. gayi provide a clear picture of necessities prescribed by the habitat. Nevertheless, by keeping a certain amount of flexibility of the design of its feeding apparatus, C. gayi is able to employ various methods of feeding.
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Affiliation(s)
- Stephanie Kunisch
- Department of Evolutionary Biology, Faculty of Life Sciences, University of Vienna, Vienna, Austria
| | - Valentin Blüml
- Department of Evolutionary Biology, Faculty of Life Sciences, University of Vienna, Vienna, Austria
| | - Thomas Schwaha
- Department of Evolutionary Biology, Faculty of Life Sciences, University of Vienna, Vienna, Austria
| | - Christian Josef Beisser
- Department of Evolutionary Biology, Faculty of Life Sciences, University of Vienna, Vienna, Austria
| | | | - Patrick Lemell
- Department of Evolutionary Biology, Faculty of Life Sciences, University of Vienna, Vienna, Austria
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14
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Prado DMA, Gomes FR, Madelaire CB. Effects of corticosterone treatment and wound healing on reproductive traits of American bullfrogs. J Exp Zool A Ecol Integr Physiol 2021; 335:275-285. [PMID: 33411410 DOI: 10.1002/jez.2439] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 11/20/2020] [Accepted: 12/18/2020] [Indexed: 11/05/2022]
Abstract
During reproductive season, calling anuran males display high testosterone (T) and episodically high corticosterone (CORT) plasma levels, which are positively associated with higher calling rates and immunocompetence. However, exposure to constant stress stimuli can result in chronically elevated CORT levels, possibly leading to inhibition of reproductive and immune activity. Reproduction and immune responses are energetically expensive, so when an animal is immunologically challenged, a tradeoff might be expressed, with CORT potentially mediating it. Our aim was to test how episodic and chronic CORT treatments, alongside wound healing, would affect reproduction in American bullfrog males (Lithobates catesbeianus). Forty animals were divided in four groups: Episodic CORT (daily transdermic application of CORT), placebo (daily transdermic application of sesame oil), chronic CORT (subcutaneous CORT silastic implants), and sham control (subcutaneous empty silastic implants). One week after treatments began, animals were punctured in the leg with a biopsy needle and the wound was photographed after 45 days to determine wound healing status (WS). Blood samples were collected throughout the experiment to measure CORT and T plasma levels. After animal euthanasia, testes were dissected, fixed, and analyzed histologically to determine spermatogenic activity (germinative cyst [GmC] morphometrics). As expected, the episodic CORT treatment had no effect on T plasma levels or spermatogenic activity. On the other hand, chronic CORT treatment reduced GmC morphometric traits, indicating suppression of reproduction, although T levels were not altered. In addition, animals from sham control and chronic CORT treatments with higher T levels presented higher WS, which indicates an immune-enhancing T effect.
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Affiliation(s)
- Débora M A Prado
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo (USP), São Paulo, São Paulo State, Brazil
| | - Fernando R Gomes
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo (USP), São Paulo, São Paulo State, Brazil
| | - Carla B Madelaire
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo (USP), São Paulo, São Paulo State, Brazil
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15
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Moore CE, Helmann JS, Chen Y, St Amour SM, Hallmark MA, Hughes LE, Wax N, Mims MC. Anuran Traits of the United States (ATraiU): a database for anuran traits-based conservation, management, and research. Ecology 2020; 102:e03261. [PMID: 33226642 DOI: 10.1002/ecy.3261] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Accepted: 10/06/2020] [Indexed: 11/10/2022]
Abstract
The United States is home to many anuran species, each with traits that set them apart from one another. Understanding trait variation within and between anurans is key to many successful conservation, management, and research efforts. However, compiling trait data is intensive and time consuming. Trait databases can meet this need, but currently there is no detailed database that collates trait data for anurans of the contiguous United States. into a single location with transparency regarding original data sources. Furthermore, many currently available trait databases rarely report multiple data points for a given species' trait, frequently reporting a single averaged value. We present an anuran traits database for the contiguous United States that includes trait data from 411 unique references. We collated trait values for 106 native and nonnative species using a tiered search protocol. First, we digitized trait data from 33 state guide books for 12 ecological, morphological, and life history traits commonly reported in the literature. We then performed a targeted search of the primary literature to address data gaps, ultimately identifying an additional 356 peer-reviewed publications, theses, and agency reports with data fitting our criteria. Finally, we digitized trait data from 22 national and regional guidebooks. Following data compilation, we conducted an intensive data quality check procedure that included both manual and statistical analyses. For full transparency, all trait values are traceable to their original reference with additional metrics (e.g., reference count, data tier) to allow users to easily filter the full data set to fit the user's needs. Overall, we report 89% of included species with trait values for at least half of the 12 traits included, providing high coverage for interspecific analyses. With a high degree of transparency, inclusion of all original data sources, and a tiered system for cataloguing data source type, ATraiU can uniquely contribute to anuran ecology and conservation in the United States. Please cite this data paper when using the data. If using a specific trait value or values, please cite the original reference(s).
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Affiliation(s)
- Chloe E Moore
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, 24060, USA
| | - Jacob S Helmann
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, 24060, USA
| | - Ye Chen
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, 24060, USA
| | - Sabine M St Amour
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, 24060, USA
| | - Mackenzi A Hallmark
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, 24060, USA
| | - London E Hughes
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, 24060, USA
| | - Noah Wax
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, 24060, USA
| | - Meryl C Mims
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, 24060, USA
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16
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McCann S, Crossland M, Greenlees M, Shine R. Field trials of chemical suppression of embryonic cane toads ( Rhinella marina) by older conspecifics. Ecol Evol 2020; 10:10177-10185. [PMID: 33005373 PMCID: PMC7520185 DOI: 10.1002/ece3.6678] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 06/03/2020] [Accepted: 06/29/2020] [Indexed: 11/13/2022] Open
Abstract
Laboratory experiments have shown that the viability of embryos of the invasive cane toad (Rhinella marina) can be reduced by exposure to chemical cues from older conspecific larvae. These effects (very strong in laboratory trials) may offer an exciting new approach to controlling this problematic invasive species in Australia. However, the degree to which the method works in natural environments has yet to be assessed.Our experiments in the laboratory and in seminatural outdoor waterbodies show that chemical cues from tadpoles do indeed suppress the growth, development, and survival of conspecific larvae that are exposed as embryos and do so in a dose-dependent manner; higher tadpole densities cause greater suppression of embryos.In seminatural outdoor waterbodies, suppressor-exposed tadpoles were less than half as likely to survive to metamorphosis as were controls, and were much smaller when they did so and hence, less likely to survive the metamorph stage. Additionally, female cane toads were less likely to oviposit in a waterbody containing free-ranging (but not cage-enclosed) tadpoles, suggesting that the presence of tadpoles (rather than the chemical cues they produce) may discourage oviposition.Broadly, our results suggest that the suppression effect documented in laboratory studies does indeed occur in the field also, and hence that we may be able to translate that approach to develop new and more effective ways to reduce rates of recruitment of peri-urban populations of cane toads in their invasive range.
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Affiliation(s)
- Samantha McCann
- School of Life and Environmental SciencesUniversity of SydneySydneyNSWAustralia
| | - Michael Crossland
- School of Life and Environmental SciencesUniversity of SydneySydneyNSWAustralia
| | - Matthew Greenlees
- School of Life and Environmental SciencesUniversity of SydneySydneyNSWAustralia
- Department of Biological SciencesMacquarie UniversitySydneyNSWAustralia
| | - Richard Shine
- School of Life and Environmental SciencesUniversity of SydneySydneyNSWAustralia
- Department of Biological SciencesMacquarie UniversitySydneyNSWAustralia
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17
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Weiss L, Jungblut LD, Pozzi AG, O’Connell LA, Hassenklöver T, Manzini I. Conservation of Glomerular Organization in the Main Olfactory Bulb of Anuran Larvae. Front Neuroanat 2020; 14:44. [PMID: 32792916 PMCID: PMC7393516 DOI: 10.3389/fnana.2020.00044] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 06/30/2020] [Indexed: 01/11/2023] Open
Abstract
The glomerular array in the olfactory bulb of many vertebrates is segregated into molecularly and anatomically distinct clusters linked to different olfactory functions. In anurans, glomerular clustering is so far only described in Xenopus laevis. We traced olfactory projections to the bulb in tadpoles belonging to six distantly related anuran species in four families (Pipidae, Hylidae, Bufonidae, Dendrobatidae) and found that glomerular clustering is remarkably conserved. The general bauplan consists of four unequally sized glomerular clusters with minor inter-species variation. During metamorphosis, the olfactory system undergoes extensive remodeling. Tracings in metamorphotic and juvenile Dendrobates tinctorius and Xenopus tropicalis suggest a higher degree of variation in the glomerular organization after metamorphosis is complete. Our study highlights, that the anatomical organization of glomeruli in the main olfactory bulb (MOB) is highly conserved, despite an extensive ecomorphological diversification among anuran tadpoles, which suggests underlying developmental constraints.
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Affiliation(s)
- Lukas Weiss
- Department of Animal Physiology and Molecular Biomedicine, Justus-Liebig-University Giessen, Giessen, Germany
| | - Lucas D. Jungblut
- Departamento de Biodiversidad y Biología Experimental, IBBEA-CONICET, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Andrea G. Pozzi
- Departamento de Biodiversidad y Biología Experimental, IBBEA-CONICET, Universidad de Buenos Aires, Buenos Aires, Argentina
| | | | - Thomas Hassenklöver
- Department of Animal Physiology and Molecular Biomedicine, Justus-Liebig-University Giessen, Giessen, Germany
| | - Ivan Manzini
- Department of Animal Physiology and Molecular Biomedicine, Justus-Liebig-University Giessen, Giessen, Germany
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18
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Weiss L, Jungblut LD, Pozzi AG, Zielinski BS, O'Connell LA, Hassenklöver T, Manzini I. Multi-glomerular projection of single olfactory receptor neurons is conserved among amphibians. J Comp Neurol 2020; 528:2239-2253. [PMID: 32080843 DOI: 10.1002/cne.24887] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 02/18/2020] [Accepted: 02/18/2020] [Indexed: 11/07/2022]
Abstract
Individual receptor neurons in the peripheral olfactory organ extend long axons into the olfactory bulb forming synapses with projection neurons in spherical neuropil regions, called glomeruli. Generally, odor map formation and odor processing in all vertebrates is based on the assumption that receptor neuron axons exclusively connect to a single glomerulus without any axonal branching. We comparatively tested this hypothesis in multiple fish and amphibian species (both sexes) by applying sparse cell electroporation to trace single olfactory receptor neuron axons. Sea lamprey (jawless fish) and zebrafish (bony fish) support the unbranched axon concept, with 94% of axons terminating in single glomeruli. Contrastingly, axonal projections of the axolotl (salamander) branch extensively before entering up to six distinct glomeruli. Receptor neuron axons labeled in frog species (Pipidae, Bufonidae, Hylidae, and Dendrobatidae) predominantly bifurcate before entering a glomerulus and 59 and 50% connect to multiple glomeruli in larval and postmetamorphotic animals, respectively. Independent of developmental stage, lifestyle, and adaptations to specific habitats, it seems to be a common feature of amphibian olfactory receptor neuron axons to frequently bifurcate and connect to multiple glomeruli. Our study challenges the unbranched axon concept as a universal vertebrate feature and it is conceivable that also later diverging vertebrates deviate from it. We propose that this unusual wiring logic evolved around the divergence of the terrestrial tetrapod lineage from its aquatic ancestors and could be the basis of an alternative way of odor processing.
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Affiliation(s)
- Lukas Weiss
- Department of Animal Physiology and Molecular Biomedicine, University of Giessen, Giessen, Germany
| | - Lucas D Jungblut
- Departamento de Biodiversidad y Biología Experimental, IBBEA-CONICET, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Andrea G Pozzi
- Departamento de Biodiversidad y Biología Experimental, IBBEA-CONICET, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Barbara S Zielinski
- Department of Integrative Biology, University of Windsor, Windsor, Ontario, Canada
| | | | - Thomas Hassenklöver
- Department of Animal Physiology and Molecular Biomedicine, University of Giessen, Giessen, Germany
| | - Ivan Manzini
- Department of Animal Physiology and Molecular Biomedicine, University of Giessen, Giessen, Germany
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19
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Abstract
The surface tension of water provides a thin, elastic membrane upon which many tiny animals are adapted to live and move. We show that it may be equally important to the minute animals living beneath it by examining air-breathing mechanics in five species (three families) of anuran (frog) tadpoles. Air-breathing is essential for survival and development in most tadpoles, yet we found that all tadpoles at small body sizes were unable to break through the water's surface to access air. Nevertheless, by 3 days post-hatch and only 3 mm body length, all began to breathe air and fill the lungs. High-speed macrovideography revealed that surface tension was circumvented by a novel behaviour we call 'bubble-sucking': mouth attachment to the water's undersurface, the surface drawn into the mouth by suction, a bubble 'pinched off' within the mouth, then compressed and forced into the lungs. Growing tadpoles transitioned to air-breathing via typical surface breaching. Salamander larvae and pulmonate snails were also discovered to 'bubble-suck', and two insects used other means of circumvention, suggesting that surface tension may have a broader impact on animal phenotypes than hitherto appreciated.
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Affiliation(s)
- Kurt Schwenk
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269-3043, USA
| | - Jackson R Phillips
- Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269-3043, USA
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20
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Yovanovich CAM, Pierotti MER, Kelber A, Jorgewich-Cohen G, Ibáñez R, Grant T. Lens transmittance shapes ultraviolet sensitivity in the eyes of frogs from diverse ecological and phylogenetic backgrounds. Proc Biol Sci 2020; 287:20192253. [PMID: 31910785 PMCID: PMC7003468 DOI: 10.1098/rspb.2019.2253] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The amount of short wavelength (ultraviolet (UV), violet and blue) light that reaches the retina depends on the transmittance properties of the ocular media, especially the lens, and varies greatly across species in all vertebrate groups studied previously. We measured the lens transmittance in 32 anuran amphibians with different habits, geographical distributions and phylogenetic positions and used them together with eye size and pupil shape to evaluate the relationship with diel activity pattern, elevation and latitude. We found an unusually high lens UV transmittance in the most basal species, and a cut-off range that extends into the visible spectrum for the rest of the sample, with lenses even absorbing violet light in some diurnal species. However, other diurnal frogs had lenses that transmit UV light like the nocturnal species. This unclear pattern in the segregation of ocular media transmittance and diel activity is shared with other vertebrates and is consistent with the absence of significant correlations in our statistical analyses. Although we did not detect a significant phylogenetic effect, closely related species tend to have similar transmittances, irrespective of whether they share the same diel pattern or not, suggesting that anuran ocular media transmittance properties might be related to phylogeny.
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Affiliation(s)
- Carola A M Yovanovich
- Department of Zoology, Institute of Biosciences, University of São Paulo, São Paulo, Brazil
| | - Michele E R Pierotti
- Department of Zoology, Institute of Biosciences, University of São Paulo, São Paulo, Brazil.,Smithsonian Tropical Research Institute, Panama City, Panama
| | - Almut Kelber
- Department of Biology, Lund University, Lund, Sweden
| | | | - Roberto Ibáñez
- Smithsonian Tropical Research Institute, Panama City, Panama
| | - Taran Grant
- Department of Zoology, Institute of Biosciences, University of São Paulo, São Paulo, Brazil
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21
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Innes-Gold AA, Zuczek NY, Touchon JC. Right phenotype, wrong place: predator-induced plasticity is costly in a mismatched environment. Proc Biol Sci 2019; 286:20192347. [PMID: 31795869 PMCID: PMC6939276 DOI: 10.1098/rspb.2019.2347] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Accepted: 11/08/2019] [Indexed: 11/12/2022] Open
Abstract
Like many animals, tadpoles often produce different, predator-specific phenotypes when exposed to risk of predation. It is generally assumed that such plasticity enhances survival in the presence of the predator and is costly elsewhere, but evidence remains surprisingly scarce. We measured (1) the survival trade-off of opposing phenotypes developed by Dendropsophus ebraccatus tadpoles when exposed to different predators and (2) which specific aspects of morphology drive any potential survival benefit or cost. Tadpoles developed predator-specific phenotypes after being reared with caged fish or dragonfly predators for two weeks. In 24 h predation trials with either a fish or a dragonfly, survival was highest in the groups with their matched predator, and lowest among with those the mismatched predator, with predator-naive controls being relatively intermediate. Then, using a large group of phenotypically variable predator-naive tadpoles, we found that increased survival rates are directly related to the morphological changes that are induced by each predator. This demonstrates that induced phenotypes are indeed adaptive and the product of natural selection. Furthermore, our data provide clear evidence of an environmental cost for phenotypic plasticity in a heterogeneous environment. Such costs are fundamental for understanding the evolution and maintenance of inducible phenotypes.
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Affiliation(s)
| | | | - Justin C. Touchon
- Biology Department, Vassar College, 124 Raymond Ave, Poughkeepsie, NY 12604, USA
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22
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Llewelyn VK, Berger L, Glass BD. Percutaneous absorption between frog species: Variability in skin may influence delivery of therapeutics. J Vet Pharmacol Ther 2019; 43:91-95. [PMID: 31769075 DOI: 10.1111/jvp.12824] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 10/22/2019] [Accepted: 10/27/2019] [Indexed: 01/19/2023]
Abstract
Frogs have permeable skin, so transdermal delivery provides a practical alternative to traditional dosing routes. However, little is known about how frog skin permeability differs interspecifically, and there are different reported clinical outcomes following topical application of the same chemical in different frog species. This study collated in vitro absorption kinetic data previously reported for two frog species: the green tree frog (Litoria caerulea) and the cane toad (Rhinella marina), and used linear mixed-effects modelling to produce a model of absorption. Histology of skin samples from each species was performed to observe morphological differences that may affect absorption. Absorption kinetics differed significantly between species, with the logP of the applied chemical a better predictor of permeability than molecular weight. Application site also influenced permeability, with dorsal permeability consistently higher in cane toads. Ventral permeability was more consistent between species. Skin thickness differed between species and skin regions, and this may explain the differences in absorption kinetics. Guidelines for selecting chemicals and dosing site when treating frogs are presented. The permeability differences identified may explain the poor reproducibility reported in the treatment of disease across frog species, and reinforces the importance of considering interspecies differences when designing therapeutic treatments for frogs.
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Affiliation(s)
- Victoria K Llewelyn
- Pharmacy, College of Medicine and Dentistry, James Cook University, Townsville, Australia
| | - Lee Berger
- One Health Research Group, Melbourne Veterinary School, University of Melbourne, Werribee, Australia
| | - Beverley D Glass
- Pharmacy, College of Medicine and Dentistry, James Cook University, Townsville, Australia
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Pushchin I. Retinal ganglion cell topography and spatial resolution estimation in the Japanese tree frog Hyla japonica (Günther, 1859). J Anat 2019; 235:1114-1124. [PMID: 31418464 DOI: 10.1111/joa.13075] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/25/2019] [Indexed: 11/29/2022] Open
Abstract
Tree frogs are an interesting and diverse group of frogs. They display a number of unique adaptations to life in the arboreal environment. Vision plays a crucial role in their ecology. The topography of retinal ganglion cells (GCs) is closely related to a species' visual behavior. Despite a large amount of research addressing GC topography in vertebrates, there is scarce data on this subject in tree frogs. I studied the topography of GCs in the retina of the Japanese tree frog Hyla japonica. The GC density distribution was locally fairly homogeneous, with spatial density increasing gradually from the dorsal and ventral periphery towards the equator. A moderately pronounced visual streak was found close to the equator in the dorsal hemiretina, with a distinct area retinae temporalis in the dorsotemporal quadrant potentially subserving binocular vision. The minimum GC density (mean ± SEM, n = 5) was 3060 ± 60 and the maximum 12 800 ± 170 cells/mm2 . The total number of GCs was 292 ± 7 × 103 . The theoretical anatomical spatial resolution estimated from GC densities and eye optics was lowest in the ventral periphery (ca. 0.9 and 1.3 cycles/degree in air and water, respectively) and highest in the area retinae temporalis (ca. 2.1 and 2.8 cycles/degree). The relatively high GC density and presence of specialized retinal regions in Hyla japonica are consistent with its highly visual behavior. The present findings contribute to our understanding of the relative role of common ancestry and environmental pressure in GC topography variation within Anura.
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Affiliation(s)
- Igor Pushchin
- Laboratory of Physiology, National Scientific Center of Marine Biology , Far Eastern Branch Russian Academy of Sciences, Vladivostok, Russia
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Sherratt E, Anstis M, Keogh JS. Ecomorphological diversity of Australian tadpoles. Ecol Evol 2018; 8:12929-12939. [PMID: 30619594 PMCID: PMC6308865 DOI: 10.1002/ece3.4733] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 10/24/2018] [Accepted: 11/01/2018] [Indexed: 01/28/2023] Open
Abstract
Ecomorphology is the association between an organism's morphology and its ecology. Larval anuran amphibians (tadpoles) are classified into distinct ecomorphological guilds based upon morphological features and observations of their ecology. The extent to which guilds comprise distinct morphologies resulting from convergent evolution, the degree of morphological variability within each guild, and the degree of continuity in shape between guilds has not previously been examined in a phylogenetically informed statistical framework. Here, we examine tadpole ecomorphological guilds at a macroevolutionary scale by examining morphological diversity across the Australian continent. We use ecological data to classify species to guilds, and geometric morphometrics to quantify body shape in the tadpoles of 188 species, 77% of Australian frog diversity. We find that the ecomorphological guilds represented by Australian species are morphologically distinct, but there is substantial morphological variation associated with each guild, and all guilds together form a morphological continuum. However, in a phylogenetic comparative context, there is no significant difference in body shape among guilds. We also relate the morphological diversity of the Australian assemblage of tadpoles to a global sample and demonstrate that ecomorphological diversity of Australian tadpoles is limited with respect to worldwide species. Our results demonstrate that general patterns of ecomorphological variation are upheld in Australian tadpoles, but tadpole body shape is more variable and possibly generalist than generally appreciated.
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Affiliation(s)
- Emma Sherratt
- Department of Ecology and Evolutionary Biology, School of Biological SciencesThe University of AdelaideAdelaideSouth AustraliaAustralia
| | - Marion Anstis
- School of Environmental and Life SciencesThe University of NewcastleCallaghanNew South WalesAustralia
- Australian Museum Research InstituteAustralian MuseumSydneyNew South WalesAustralia
| | - J. Scott Keogh
- Division of Ecology & Evolution, Research School of BiologyThe Australian National UniversityCanberraAustralian Capital TerritoryAustralia
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Targueta CP, Guerra V, Gambale PG, Bastos RP, Silva DDME, Telles MPDC. Cytogenetics of two hylid frogs from Brazilian Cerrado. Genet Mol Biol 2018; 41:814-819. [PMID: 30508007 PMCID: PMC6415605 DOI: 10.1590/1678-4685-gmb-2017-0382] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2017] [Accepted: 04/10/2018] [Indexed: 11/22/2022] Open
Abstract
Cytogenetic data can be useful for taxonomic and phylogenetic studies, as well as to provide information about chromosome evolution. Therefore, it may help design conservation priorities for some threatened species, such as anurans. Herein, we describe the karyotypes of Scinax constrictus and Ololygon centralis, native endemic species from the Brazilian Cerrado. Chromosome preparations for both species were stained with Giemsa for morphological analyses and then impregnated by the Ag-NOR method for localization of the nucleolar organizer region (NOR). Both species had 24 chromosomes, as confirmed by meiotic analyses, which showed 12 bivalents. Chromosome morphologies presented the same pattern for Scinax and Ololygon compared to species already karyotyped in both genera. The NOR was interstitially located in the long arm of pair 7 in S. constrictus, whereas in O. centralis it was found near the centromere in the long arm of pair 1, thus diverging from what is commonly found for other Ololygon species. Therefore, we provide the first description of the karyotype of O. centralis and the first report of the localization of the NOR for the karyotype of both species. Our study increases the cytogenetic knowledge in species of the genera Scinax and Ololygon, and provide support for further studies on the taxonomy, ecology, and evolution of hylid anurans.
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Affiliation(s)
- Cíntia Pelegrineti Targueta
- Laboratório de Genética & Biodiversidade, Departamento de Genética, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, GO, Brazil
| | - Vinícius Guerra
- Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais, Universidade Estadual de Maringá, Maringá, PR, Brazil
| | - Priscilla Guedes Gambale
- Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais, Universidade Estadual de Maringá, Maringá, PR, Brazil
| | - Rogério Pereira Bastos
- Departamento de Ecologia, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, GO, Brazil
| | - Daniela de Melo e Silva
- Laboratório de Mutagênese, Departamento de Genética, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, GO, Brazil
| | - Mariana Pires de Campos Telles
- Laboratório de Genética & Biodiversidade, Departamento de Genética, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, GO, Brazil
- Escola de Ciências Agrárias e Biológicas, Pontifícia Universidade Católica de Goiás, Goiânia, GO, Brazil
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Saporito RA, Grant T. Comment on Amézquita et al. (2017) "Conspicuousness, color resemblance, and toxicity in geographically diverging mimicry: The pan-Amazonian frog Allobates femoralis". Evolution 2018. [PMID: 29524217 DOI: 10.1111/evo.13468] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Amézquita et al. (2017) recently concluded that species of the Allobates femoralis group are toxic to mice at levels equivalent to syntopic alkaloid-containing poison frogs, which they attributed to the presence of alkaloids in skin secretions. However, the chemical composition of skin secretions was not analyzed, and here we present additional data supporting the absence of alkaloids in skin secretions of the Allobates femoralis group. Instead, we suggest the observed toxicity was caused by the anesthetic benzocaine, which was applied to the buccal cavity to euthanize frogs prior to skin removal. We show that orally administered benzocaine is rapidly incorporated into the skin of species that sequester and do not sequester alkaloids, which casts doubt on the conclusion that Allobates femoralis group skin secretions are toxic and makes the results of experiments with alkaloid-containing species of Adelphobates and Ameerega uninterpretable. To prevent experimental errors and misinterpretations in studies of amphibian chemical defense, we encourage researchers to test the chemical composition of samples prior to experimentation, include all necessary controls to detect false positives, conduct small pilot studies for new methods, and consider the limitations of particular methods and their ability to address the intended research questions.
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Affiliation(s)
- Ralph A Saporito
- Department of Biology, John Carroll University, University Heights, Ohio 44118
| | - Taran Grant
- Department de Zoology, Institute of Biosciences, University of São Paulo, 05508, São Paulo, São Paulo, Brazil
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Lukas P, Olsson L. Sequence and timing of early cranial skeletal development in Xenopus laevis. J Morphol 2017; 279:62-74. [PMID: 28960402 DOI: 10.1002/jmor.20754] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 09/01/2017] [Accepted: 09/05/2017] [Indexed: 12/13/2022]
Abstract
Xenopus laevis is widely used as a model organism in biological research. Morphological descriptions of the larval cartilaginous skeleton are more than half a century old and comprehensive studies of early cartilage differentiation and development are missing. A proper understanding of early cranial skeletal development in X. laevis requires a detailed description that can function as a baseline for experimental studies. This basis makes it possible to evaluate skeletal defects produced by experiments on gene interactions, such as gain- or loss-of function experiments. In this study, we provide a detailed description of the pattern and timing of early cartilage differentiation and development in the larval head of X. laevis. Methods used include antibody staining, confocal laser scanning microscopy and 3D-reconstruction. Results were than compared to earlier studies based on classical histological approaches and clearing-and-staining. The first cartilage to chondrify is, in contrast to other vertebrates investigated so far, the ceratohyal. The components of the branchial basket chondrify in anterior-to-posterior direction as reported for other amphibians. Chondrification of different cartilages begins at different stages and the majority of cartilages are fully developed at Ziermann and Olsson stage 17. Our baseline data on the pattern and timing of early cartilaginous development in X. laevis is useful for evaluation of experiments which alter head skeletal development as well as for identifying heterochronic shifts in head development in other amphibians.
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Affiliation(s)
- Paul Lukas
- Institut für Spezielle Zoologie und Evolutionsbiologie mit Phyletischem Museum, Friedrich-Schiller-Universität, Jena, Germany
| | - Lennart Olsson
- Institut für Spezielle Zoologie und Evolutionsbiologie mit Phyletischem Museum, Friedrich-Schiller-Universität, Jena, Germany
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dos Santos JS, Introíni GO, Veiga-Menoncello ACP, Recco-Pimentel SM. Ultrastructure variation in the spermatozoa of Pseudopaludicola frogs (Amphibia, Anura, Leptodactylidae), with brief comments on its phylogenetic relevance. J Morphol 2015; 276:1495-504. [PMID: 26352290 DOI: 10.1002/jmor.20438] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2015] [Revised: 08/07/2015] [Accepted: 08/16/2015] [Indexed: 11/11/2022]
Abstract
The taxonomic history of the small frogs of the genus Pseudopaludicola from South America has been controversial. Phylogenetic inferences based on molecular data have identified four Pseudopaludicola clades, correlating with the known variation in karyotypes (2n = 22, 20, 18, and 16). In this study, the ultrastructure of the spermatozoa was analyzed in 12 species of the Pseudopaludicola, with the aim of describing their morphology and identifying characters that may contribute to a better understanding of the phylogenetic relationships. The spermatozoa presented marked differences in tail structures. The tails of the spermatozoa of the species with 2n = 22 chromosomes (Pseudopaludicola sp. 1 [P. pusilla group], Pseudopaludicola falcipes, P. mineira, and Pseudopaludicola saltica), as well as Pseudopaludicola ameghini and Pseudopaludicola ternetzi (2n=20), have juxta-axonemal fibers, undulating membranes and axial fibers. In contrast, in the species with 2n = 18 (P. facureae, P. giarettai, Pseudopaludicola canga, P. atragula, and Pseudopaludicola sp. 2) and 2n = 16 (Pseudopaludicola mystacalis), there are no evident axial or juxta-axonemal fibers, but a paraxonemal rod with a thick undulating membrane, which is shorter than that found among Pseudopaludicola species. The ultrastructural morphological differences observed in the spermatozoa of these species may be phylogenetically informative, given that they coincide with the consensus phylogeny of the group and appear to represent a progressive simplification of the spermatozoon.
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Affiliation(s)
- Julio Sérgio dos Santos
- Departamento de Biologia Estrutural e Funcional, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), 13083-863 Campinas, São Paulo, Brazil
| | - Gisele Orlandi Introíni
- Departamento de Biologia Estrutural e Funcional, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), 13083-863 Campinas, São Paulo, Brazil.,Departamento de Ciências Básicas da Saúde, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), 245, Porto Alegre, Rio Grande do Sul, 90050-170, Brazil
| | - Ana Cristina Prado Veiga-Menoncello
- Departamento de Biologia Estrutural e Funcional, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), 13083-863 Campinas, São Paulo, Brazil
| | - Shirlei Maria Recco-Pimentel
- Departamento de Biologia Estrutural e Funcional, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), 13083-863 Campinas, São Paulo, Brazil
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Barej MF, Schmitz A, Günther R, Loader SP, Mahlow K, Rödel MO. The first endemic West African vertebrate family - a new anuran family highlighting the uniqueness of the Upper Guinean biodiversity hotspot. Front Zool 2014; 11:8. [PMID: 24485269 PMCID: PMC3925359 DOI: 10.1186/1742-9994-11-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 12/21/2013] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Higher-level systematics in amphibians is relatively stable. However, recent phylogenetic studies of African torrent-frogs have uncovered high divergence in these phenotypically and ecologically similar frogs, in particular between West African torrent-frogs versus Central (Petropedetes) and East African (Arthroleptides and Ericabatrachus) lineages. Because of the considerable molecular divergence, and external morphology of the single West African torrent-frog species a new genus was erected (Odontobatrachus). In this study we aim to clarify the systematic position of West African torrent-frogs (Odontobatrachus). We determine the relationships of torrent-frogs using a multi-locus, nuclear and mitochondrial, dataset and include genera of all African and Asian ranoid families. Using micro-tomographic scanning we examine osteology and external morphological features of West African torrent-frogs to compare them with other ranoids. RESULTS Our analyses reveal Petropedetidae (Arthroleptides, Ericabatrachus, Petropedetes) as the sister taxon of the Pyxicephalidae. The phylogenetic position of Odontobatrachus is clearly outside Petropedetidae, and not closely related to any other ranoid family. According to our time-tree estimation Odontobatrachus has been separated from other frog lineages since the Cretaceous (90.1 Ma; confidence interval: 84.2-97.1 Ma). Along with this molecular evidence, osteological and external diagnostic characters recognize West African torrent-frogs as distinct from other ranoids and provide strong support for the necessity of the recognition of a new family of frogs. This is the only endemic vertebrate family occurring in the Upper Guinea biodiversity hotspot. CONCLUSION Based on molecular and morphological distinctiveness, the West African torrent-frog Odontobatrachus natator is allocated to a newly described anuran family. The discovery of an endemic vertebrate family in West Africa highlights the Upper Guinean forests as an outstanding, but highly endangered biodiversity hotspot.
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Affiliation(s)
- Michael F Barej
- Museum für Naturkunde, Leibniz Institute for Research on Evolution and Biodiversity, Invalidenstrasse 43, D-10115 Berlin, Germany
| | - Andreas Schmitz
- Department of Herpetology and Ichthyology, Natural History Museum of Geneva, CP 6434, 1211 Geneva 6, Switzerland
| | - Rainer Günther
- Museum für Naturkunde, Leibniz Institute for Research on Evolution and Biodiversity, Invalidenstrasse 43, D-10115 Berlin, Germany
| | - Simon P Loader
- Department of Environmental Sciences (Biogeography), University of Basel, Klingelbergstr. 27, Basel 4056, Switzerland
| | - Kristin Mahlow
- Museum für Naturkunde, Leibniz Institute for Research on Evolution and Biodiversity, Invalidenstrasse 43, D-10115 Berlin, Germany
| | - Mark-Oliver Rödel
- Museum für Naturkunde, Leibniz Institute for Research on Evolution and Biodiversity, Invalidenstrasse 43, D-10115 Berlin, Germany
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Medeiros LR, Lourenço LB, Rossa-Feres DC, Lima AP, Andrade GV, Giaretta AA, Egito GTBT, Recco-Pimentel SM. Comparative cytogenetic analysis of some species of the Dendropsophus microcephalus group ( Anura, Hylidae) in the light of phylogenetic inferences. BMC Genet 2013; 14:59. [PMID: 23822759 PMCID: PMC3710474 DOI: 10.1186/1471-2156-14-59] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Accepted: 06/20/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Dendropsophus is a monophyletic anuran genus with a diploid number of 30 chromosomes as an important synapomorphy. However, the internal phylogenetic relationships of this genus are poorly understood. Interestingly, an intriguing interspecific variation in the telocentric chromosome number has been useful in species identification. To address certain uncertainties related to one of the species groups of Dendropsophus, the D. microcephalus group, we carried out a cytogenetic analysis combined with phylogenetic inferences based on mitochondrial sequences, which aimed to aid in the analysis of chromosomal characters. Populations of Dendropsophus nanus, Dendropsophus walfordi, Dendropsophus sanborni, Dendropsophus jimi and Dendropsophus elianeae, ranging from the extreme south to the north of Brazil, were cytogenetically compared. A mitochondrial region of the ribosomal 12S gene from these populations, as well as from 30 other species of Dendropsophus, was used for the phylogenetic inferences. Phylogenetic relationships were inferred using maximum parsimony and Bayesian analyses. RESULTS The species D. nanus and D. walfordi exhibited identical karyotypes (2n = 30; FN = 52), with four pairs of telocentric chromosomes and a NOR located on metacentric chromosome pair 13. In all of the phylogenetic hypotheses, the paraphyly of D. nanus and D. walfordi was inferred. D. sanborni from Botucatu-SP and Torres-RS showed the same karyotype as D. jimi, with 5 pairs of telocentric chromosomes (2n = 30; FN = 50) and a terminal NOR in the long arm of the telocentric chromosome pair 12. Despite their karyotypic similarity, these species were not found to compose a monophyletic group. Finally, the phylogenetic and cytogenetic analyses did not cluster the specimens of D. elianeae according to their geographical occurrence or recognized morphotypes. CONCLUSIONS We suggest that a taxonomic revision of the taxa D. nanus and D. walfordi is quite necessary. We also observe that the number of telocentric chromosomes is useful to distinguish among valid species in some cases, although it is unchanged in species that are not necessarily closely related phylogenetically. Therefore, inferences based on this chromosomal character must be made with caution; a proper evolutionary analysis of the karyotypic variation in Dendropsophus depends on further characterization of the telocentric chromosomes found in this group.
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Affiliation(s)
- Lilian Ricco Medeiros
- Departamento de Biologia Estrutural e Funcional, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), 13086-863, Campinas, SP, Brazil
| | - Luciana Bolsoni Lourenço
- Departamento de Biologia Estrutural e Funcional, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), 13086-863, Campinas, SP, Brazil
| | - Denise Cerqueira Rossa-Feres
- Departamento de Zoologia e Botânica, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista (UNESP), 15054-000, São José do Rio Preto, São Paulo, Brazil
| | - Albertina Pimentel Lima
- Coordenadoria de Pesquisas em Ecologia, Instituto Nacional de Pesquisas da Amazônia (INPA), 69011-970, Manaus, AM, Brazil
| | - Gilda Vasconcellos Andrade
- Departamento de Biologia, Centro de Ciências Biológicas e da Saúde, Universidade Federal do Maranhão (UFMA), Campus do Bacanga, 65080-040, São Luís, MA, Brazil
| | - Ariovaldo Antonio Giaretta
- Laboratório de Anuros Neotropicais, Faculdade de Ciências Integradas do Pontal, Universidade Federal de Uberlândia, 38304-402, Ituiutaba, MG, Brazil
| | - Gabriel Toselli Barbosa Tabosa Egito
- Departamento de Biologia Estrutural e Funcional, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), 13086-863, Campinas, SP, Brazil
- Departamento de Polícia Federal, Ministério da Justiça, 68908-901, Macapá, AP, Brazil
| | - Shirlei Maria Recco-Pimentel
- Departamento de Biologia Estrutural e Funcional, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), 13086-863, Campinas, SP, Brazil
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Abstract
Many invasive species have evolved behavioural and morphological characteristics that facilitate their dispersal into new areas, but it is unclear how selection on this level of the phenotype filters through to the underlying physiology. Cane toads have been dispersing westward across northern tropical Australia for more than 70 years. Previous studies of cane toads at the invasive front have identified several behavioural, morphological and locomotory characteristics that have evolved to facilitate dispersal of toads. We assessed a range of physiological characteristics associated with locomotory abilities in toads from the long-established, east coast of Australia, from the invasive front, and from a site in between these locations. We measured time to exhaustion and respiratory gases of toads exercising on a treadmill, time to recovery from exhaustion, blood properties (lactate, haematocrit, haemoglobin, red blood cell count, blood cell volume), and muscle properties associated with locomotion (activities of the enzymes citrate synthase and lactate dehydrogenase, and pH buffering capacity). None of the measured physiological parameters supported the hypothesis that toads from the invasive front possess physiological adaptations that facilitate dispersal compared to toads from areas colonised in the past. The strongest difference among the three groups of toads, time to exhaustion, showed exactly the opposite trend; toads from the long-established populations in the east coast had the longest time to exhaustion. Successful colonisers can employ many characteristics to facilitate their dispersal, so the extent to which behaviour, morphology and physiology co-evolve remains an interesting question. However, in the present case at least, behavioural adaptations do not appear to have altered the organism's underlying physiology.
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Affiliation(s)
- Christopher R Tracy
- Research Institute for the Environment and Livelihoods, Charles Darwin University , Northern Territory 0909 , Australia ; Department of Zoology, University of Melbourne , Parkville, Victoria 3010 , Australia
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Ohba SY, Kawada H, Dida GO, Juma D, Sonye G, Minakawa N, Takagi M. Predators of Anopheles gambiae sensu lato (Diptera: Culicidae) larvae in wetlands, western Kenya: confirmation by polymerase chain reaction method. J Med Entomol 2010; 47:783-7. [PMID: 20939371 PMCID: PMC2980855 DOI: 10.1603/me10051] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Polymerase chain reaction analysis was performed to determine whether mosquito predators in wetland habitats feed on Anopheles gambiae sensu lato (s.l.) larvae. Aquatic mosquito predators were collected from six wetlands near Lake Victoria in Mbita, Western Kenya. This study revealed that the whole positive rate of An. gambiae s.l. from 330 predators was 54.2%. The order of positive rate was the highest in Odonata (70.2%), followed by Hemiptera (62.8%), Amphibia (41.7%), and Coleoptera (18%). This study demonstrates that the polymerase chain reaction method can determine whether aquatic mosquito predators feed on An. gambiae s.l. larvae if the predators have undigested An. gambiae s.l. in their midgut or stomach.
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Affiliation(s)
- Shin-Ya Ohba
- Department of Vector Ecology and Environment, Institute of Tropical Medicine and the Global Center of Excellence Program, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan.
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Evans SE, Jones MEH, Krause DW. A giant frog with South American affinities from the Late Cretaceous of Madagascar. Proc Natl Acad Sci U S A 2008; 105:2951-6. [PMID: 18287076 PMCID: PMC2268566 DOI: 10.1073/pnas.0707599105] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2007] [Indexed: 11/18/2022] Open
Abstract
Madagascar has a diverse but mainly endemic frog fauna, the biogeographic history of which has generated intense debate, fueled by recent molecular phylogenetic analyses and the near absence of a fossil record. Here, we describe a recently discovered Late Cretaceous anuran that differs strikingly in size and morphology from extant Malagasy taxa and is unrelated either to them or to the predicted occupants of the Madagascar-Seychelles-India landmass when it separated from Africa 160 million years ago (Mya). Instead, the previously undescribed anuran is attributed to the Ceratophryinae, a clade previously considered endemic to South America. The discovery offers a rare glimpse of the anuran assemblage that occupied Madagascar before the Tertiary radiation of mantellids and microhylids that now dominate the anuran fauna. In addition, the presence of a ceratophryine provides support for a controversial paleobiogeographical model that posits physical and biotic links among Madagascar, the Indian subcontinent, and South America that persisted well into the Late Cretaceous. It also suggests that the initial radiation of hyloid anurans began earlier than proposed by some recent estimates.
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Affiliation(s)
- Susan E. Evans
- *Research Department of Cell and Developmental Biology, Anatomy Building, UCL, University College London, Gower Street, London WC1E 6BT, United Kingdom; and
| | - Marc E. H. Jones
- *Research Department of Cell and Developmental Biology, Anatomy Building, UCL, University College London, Gower Street, London WC1E 6BT, United Kingdom; and
| | - David W. Krause
- Department of Anatomical Sciences, Stony Brook University, Stony Brook, NY 11794-8081
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Abstract
The nasal capsules of anurans are formed by an intricate set of sac-like cavities that house the olfactory organ and constitute the beginning of the respiratory system. In tadpoles, nasal capsules do not have a respiratory function, but each is composed of a single soft tissue cavity lined with olfactory epithelium. Our study has revealed that in Spea the nasal cartilages and septomaxillae are de novo adult structures that form dorsal to the larval skeleton of the ethmoid region. The only element of the adult nasal capsule that is partially derived from the larval skeleton is the solum nasi. Development of the nasal skeleton begins at about Gosner Stage 31, with chondrification of the septum nasi and lamina orbitonasalis. The alary cartilage and superior prenasal cartilage are the first of the anterior nasal cartilages to chondrify at Gosner Stage 37. By Gosner Stages 40/41, the ethmoid region is composed of the larval structures ventrally and the adult structures dorsally. By Stage 44, the larval structures have eroded. The adult nasal capsule is characterized by: (1) a septum nasi that projects ventrally beyond the plane of the nasal floor; (2) a paranasal commissure that forms the ventral margin of the fenestra nasolateralis; and (3) a large skeletal support for the eminentia olfactoria formed by the nasal floor and vomer. The timing of chondrification of the anterior nasal cartilages and the development of the postnasal wall, inferior prenasal cartilage, fenestra nasolateralis, and paranasal commissure are discussed and compared with those of other anuran species. This study also includes a discussion of the morphology of the skeletal support for the eminentia olfactoria, a structure best developed in distinctly ground-dwelling frogs such as spadefoot toads. Finally, we propose a more precise restriction of the terminology that is used to designate the posterior structures of the olfactory region of anurans.
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Affiliation(s)
- L A Pugener
- Department of Biological Sciences, University of Missouri-Rolla, Missouri 65409, USA.
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Kolesová H, Lametschwandtner A, Rocek Z. The evolution of amphibian metamorphosis: insights based on the transformation of the aortic arches of Pelobates fuscus ( Anura). J Anat 2007; 210:379-93. [PMID: 17367494 PMCID: PMC2100297 DOI: 10.1111/j.1469-7580.2007.00710.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/18/2007] [Indexed: 11/29/2022] Open
Abstract
In order to gain insights into how the aortic arches changed during the transition of vertebrates to land, transformations of the aortic arches during the metamorphosis of Pelobates fuscus were investigated and compared with data from the early development of a recent ganoid fish Amia calva and a primitive caudate amphibian Salamandrella keyserlingi. Although in larval Pelobates, as in other non-pipid anurans, the gill arches serve partly as a filter-feeding device, their aortic arches maintain the original piscine-like arrangement, except for the mandibular and hyoid aortic arches which were lost. As important pre-adaptations for breathing of atmospheric oxygen occur in larval Pelobates (which have well-developed, though non-respiratory lungs and pulmonary artery), transformation of aortic arches during metamorphosis is fast. The transformation involves disappearance of the ductus Botalli, which results in a complete shunting of blood into the lungs and skin, disappearance of the ductus caroticus, which results in shunting of blood into the head through the arteria carotis interna, and disappearance of arch V, which results in shunting blood to the body through arch IV (systemic arch). It is supposed that the branching pattern of the aortic arches of permanently water-dwelling piscine ancestors, of intermediate forms which occasionally left the water and of primitive tetrapods capable of spending longer periods of time on land had been the same as in the prematamorphic anuran larvae or in some metamorphosed caudates in which the ductus caroticus and ductus Botalli were not interrupted, and arch V was still complete.
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Affiliation(s)
- Hana Kolesová
- Institute of Anatomy, First Faculty of Medicine, Charles University, Prague, Czech Republic.
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36
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Abstract
The phylogenetic relationships among the three orders of modern amphibians (Caudata, Gymnophiona, and Anura) have been estimated based on both morphological and molecular evidence. Most morphological and paleontological studies of living and fossil amphibians support the hypothesis that salamanders and frogs are sister lineages (the Batrachia hypothesis) and that caecilians are more distantly related. Previous interpretations of molecular data based on nuclear and mitochondrial rRNA sequences suggested that salamanders and caecilians are sister groups to the exclusion of frogs. In an attempt to resolve this apparent conflict, the complete mitochondrial genomes of a salamander (Mertensiella luschani) and a caecilian (Typhlonectes natans) were determined (16,656 and 17,005 bp, respectively) and compared with previously published sequences from a frog (Xenopus laevis) and several other groups of vertebrates. Phylogenetic analyses of the mitochondrial data supported with high bootstrap values the monophyly of living amphibians with respect to other living groups of tetrapods, and a sister group relationship of salamanders and frogs. The lack of phylogenetically informative sites in the previous rRNA data sets (because of its shorter size and higher among-site rate variation) likely explains the discrepancy between our results and those based on previous molecular data. Strong support of the Batrachia hypothesis from both molecule- and morphology-based studies provides a robust phylogenetic framework that will be helpful to comparative studies among the three living orders of amphibians and will permit better understanding of the considerably divergent vertebral, brain, and digit developmental patterns found in frogs and salamanders.
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Affiliation(s)
- R Zardoya
- Museo Nacional de Ciencias Naturales, José Gutierrez Abascal, 2, 28006 Madrid,
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