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Twomey E, Melo-Sampaio P, Schulte LM, Bossuyt F, Brown JL, Castroviejo-Fisher S. Multiple Routes to Color Convergence in a Radiation of Neotropical Poison Frogs. Syst Biol 2023; 72:1247-1261. [PMID: 37561391 PMCID: PMC10924724 DOI: 10.1093/sysbio/syad051] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 08/03/2023] [Accepted: 08/09/2023] [Indexed: 08/11/2023] Open
Abstract
Convergent evolution is defined as the independent evolution of similar phenotypes in different lineages. Its existence underscores the importance of external selection pressures in evolutionary history, revealing how functionally similar adaptations can evolve in response to persistent ecological challenges through a diversity of evolutionary routes. However, many examples of convergence, particularly among closely related species, involve parallel changes in the same genes or developmental pathways, raising the possibility that homology at deeper mechanistic levels is an important facilitator of phenotypic convergence. Using the genus Ranitomeya, a young, color-diverse radiation of Neotropical poison frogs, we set out to 1) provide a phylogenetic framework for this group, 2) leverage this framework to determine if color phenotypes are convergent, and 3) to characterize the underlying coloration mechanisms to test whether color convergence occurred through the same or different physical mechanisms. We generated a phylogeny for Ranitomeya using ultraconserved elements and investigated the physical mechanisms underlying bright coloration, focusing on skin pigments. Using phylogenetic comparative methods, we identified several instances of color convergence, involving several gains and losses of carotenoid and pterin pigments. We also found a compelling example of nonparallel convergence, where, in one lineage, red coloration evolved through the red pterin pigment drosopterin, and in another lineage through red ketocarotenoids. Additionally, in another lineage, "reddish" coloration evolved predominantly through structural color mechanisms. Our study demonstrates that, even within a radiation of closely related species, convergent evolution can occur through both parallel and nonparallel mechanisms, challenging the assumption that similar phenotypes among close relatives evolve through the same mechanisms.
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Affiliation(s)
- Evan Twomey
- Department of Wildlife/Zoo Animal Biology and Systematics, Faculty of Biological Sciences, Goethe University Frankfurt, Max-von-Laue-Str. 13, Frankfurt am Main 60438, Germany
| | - Paulo Melo-Sampaio
- Departamento de Vertebrados, Museu Nacional, Universidade Federal do Rio de Janeiro, R. Gen. Herculano Gomes 41, Rio de Janeiro 20941-360, Brazil
| | - Lisa M Schulte
- Department of Wildlife/Zoo Animal Biology and Systematics, Faculty of Biological Sciences, Goethe University Frankfurt, Max-von-Laue-Str. 13, Frankfurt am Main 60438, Germany
| | - Franky Bossuyt
- Amphibian Evolution Laboratory, Biology Department, Vrije Universiteit Brussel, Pleinlaan 2, Brussels 1050, Belgium
| | - Jason L Brown
- School of Biological Sciences, Southern Illinois University, 125 Lincoln Dr., Carbondale, IL 62901, USA
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Schulte LM, Jendras J, Twomey E, Ramirez-Bautista A, Bossuyt F. Gene expression of secretory proteins in the nuptial pads of three Lithobates species (Anura: Ranidae). AMPHIBIA-REPTILIA 2022. [DOI: 10.1163/15685381-bja10108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Abstract
Many amphibian species possess male-specific secretory breeding glands. In anurans, such specialized glands are often present as nuptial pads at the first digit of the hand, which are pressed against the female during amplexus. However, the role of nuptial pad secretions remains largely unknown. Here, we investigate the inner morphology as well as the RNA expression patterns of the nuptial pads of several Central American Lithobates species (Ranidae). As shown for the breeding glands of other amphibian species, the Lithobates nuptial pads are composed of large specialized mucus glands, excreting proteinaceous content to the surface. Whole-transcriptome sequencing revealed that for one of the species the most highly expressed transcripts encoding secretory proteins in the nuptial pads are sodefrin precursor-like factor (SPF) proteins, known to have a pheromone function in multiple amphibian species. The other two species, however, lack high expression of SPF transcripts but express other secretory proteins, whose roles in amphibian breeding glands remain unknown. Several of these proteins are highly expressed in all samples, suggesting a direct role during courtship or for the maintenance/development of the glands.
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Affiliation(s)
- Lisa M. Schulte
- Department of Wildlife-/Zoo-Animal-Biology and Systematics, Faculty of Biological Sciences, Goethe University Frankfurt, Max-von-Laue-Str. 13, 60438 Frankfurt/Main, Germany
| | - Julia Jendras
- Department of Wildlife-/Zoo-Animal-Biology and Systematics, Faculty of Biological Sciences, Goethe University Frankfurt, Max-von-Laue-Str. 13, 60438 Frankfurt/Main, Germany
| | - Evan Twomey
- Department of Wildlife-/Zoo-Animal-Biology and Systematics, Faculty of Biological Sciences, Goethe University Frankfurt, Max-von-Laue-Str. 13, 60438 Frankfurt/Main, Germany
| | - Aurelio Ramirez-Bautista
- Laboratorio de Ecología de Poblaciones, Centro de Investigaciones Biológicas, Instituto de Ciencias Básicas e Ingeniería, Universidad Autónoma del Estado de Hidalgo, Km 4.5 carretera Pachuca-Tulancingo, 42184, Mineral de La Reforma, Hidalgo, México
| | - Franky Bossuyt
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium
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Schulte LM, Martel A, Cruz-Elizalde R, Ramírez-Bautista A, Bossuyt F. Love bites: male frogs (Plectrohyla, Hylidae) use teeth scratching to deliver sodefrin precursor-like factors to females during amplexus. Front Zool 2021; 18:59. [PMID: 34823558 PMCID: PMC8613984 DOI: 10.1186/s12983-021-00445-6] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 11/09/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Efficient transfer of chemical signals is important for successful mating in many animal species. Multiple evolutionary lineages of animals evolved direct sex pheromone transmission during traumatic mating-the wounding of the partner with specialized devices-which helps to avoid signal loss to the environment. Although such direct transmission modes of so-called allohormone pheromones are well-documented in invertebrates, they are considered rare in vertebrates. Males of several species of the frog genus Plectrohyla (Hylidae, Anura) have elongated teeth and develop swollen lips during the breeding season. Here we investigated the possibility that these structures are used to scratch the females' skin and apply allohormone pheromones during traumatic mating in several Plectrohyla species. RESULTS Our behavioural observations revealed that males press their upper jaw onto the females' dorsum during amplexus, leaving small skin scratches with their teeth. Histological examinations of the males' lips identified specialized mucus glands, resembling known amphibian pheromone glands. Whole-transcriptome sequencing of these breeding glands showed high expression of sodefrin precursor-like factor (SPF) proteins, which are known to have a pheromone function in multiple amphibian species. CONCLUSIONS Our study suggests SPF delivery via traumatic mating in several anuran species: the males have specialized breeding glands in the lips for production and secretion and use their elongated teeth as wounding devices for application. We hypothesize that these SPF proteins end up in the females' circulatory system, where understanding their exact function will require further molecular, physiological and behavioural testing.
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Affiliation(s)
- Lisa M Schulte
- Department of Wildlife-/Zoo-Animal-Biology and Systematics, Faculty of Biological Sciences, Goethe University Frankfurt, Max-von-Laue-Str. 13, 60438, Frankfurt/Main, Germany.
| | - An Martel
- Wildlife Health, Ghent University, Salisburylaan 133, 9820, Merelbeke, Belgium
| | - Raciel Cruz-Elizalde
- Laboratorio de Zoología, Facultad de Ciencias Naturales, Universidad Autónoma de Querétaro, Avenida de Las Ciencias S/N, Santa Fe Juriquilla, C. P. 76230, Querétaro, Mexico
| | - Aurelio Ramírez-Bautista
- Laboratorio de Ecología de Poblaciones, Centro de Investigaciones Biológicas, Instituto de Ciencias Básicas E Ingeniería, Universidad Autónoma del Estado de Hidalgo, Km 4.5 carretera Pachuca-Tulancingo, 42184, Mineral de La Reforma, Hidalgo, Mexico
| | - Franky Bossuyt
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050, Brussels, Belgium
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Janssenswillen S, Roelants K, Carpentier S, de Rooster H, Metzemaekers M, Vanschoenwinkel B, Proost P, Bossuyt F. Odorant-binding proteins in canine anal sac glands indicate an evolutionarily conserved role in mammalian chemical communication. BMC Ecol Evol 2021; 21:182. [PMID: 34565329 PMCID: PMC8474896 DOI: 10.1186/s12862-021-01910-w] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 09/10/2021] [Indexed: 11/29/2022] Open
Abstract
Background Chemical communication is an important aspect of the behavioural ecology of a wide range of mammals. In dogs and other carnivores, anal sac glands are thought to convey information to conspecifics by secreting a pallet of small volatile molecules produced by symbiotic bacteria. Because these glands are unique to carnivores, it is unclear how their secretions relate to those of other placental mammals that make use of different tissues and secretions for chemical communication. Here we analyse the anal sac glands of domestic dogs to verify the secretion of proteins and infer their evolutionary relationship to those involved in the chemical communication of non-carnivoran mammals. Results Proteomic analysis of anal sac gland secretions of 17 dogs revealed the consistently abundant presence of three related proteins. Homology searches against online databases indicate that these proteins are evolutionary related to ‘odorant binding proteins’ (OBPs) found in a wide range of mammalian secretions and known to contribute to chemical communication. Screening of the dog’s genome sequence show that the newly discovered OBPs are encoded by a single cluster of three genes in the pseudoautosomal region of the X-chromosome. Comparative genomic screening indicates that the same locus is shared by a wide range of placental mammals and that it originated at least before the radiation of extant placental orders. Phylogenetic analyses suggest a dynamic evolution of gene duplication and loss, resulting in large gene clusters in some placental taxa and recurrent loss of this locus in others. The homology of OBPs in canid anal sac glands and those found in other mammalian secretions implies that these proteins maintained a function in chemical communication throughout mammalian evolutionary history by multiple shifts in expression between secretory tissues involved in signal release and nasal mucosa involved in signal reception. Conclusions Our study elucidates a poorly understood part of the biology of a species that lives in close association with humans. In addition, it shows that the protein repertoire underlying chemical communication in mammals is more evolutionarily stable than the variation of involved glands and tissues would suggest. Supplementary Information The online version contains supplementary material available at 10.1186/s12862-021-01910-w.
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Affiliation(s)
- Sunita Janssenswillen
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel, Pleinlaan 2, 1050, Brussels, Belgium
| | - Kim Roelants
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel, Pleinlaan 2, 1050, Brussels, Belgium.
| | - Sebastien Carpentier
- Proteomics Core - SyBioMa, Katholieke Universiteit Leuven, Herestraat 49 - 03.313, 3000, Leuven, Belgium
| | - Hilde de Rooster
- Small Animal Department, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820, Merelbeke, Belgium
| | - Mieke Metzemaekers
- Rega Institute, Molecular Immunology, Katholieke Universiteit Leuven, Herestraat 49 - Bus1042, 3000, Leuven, Belgium
| | - Bram Vanschoenwinkel
- Community Ecology Lab, Biology Department, Vrije Universiteit Brussel, Pleinlaan 2, 1050, Brussels, Belgium.,Center for Environmental Management, University of the Free State, Bloemfontein, 9030, South Africa
| | - Paul Proost
- Rega Institute, Molecular Immunology, Katholieke Universiteit Leuven, Herestraat 49 - Bus1042, 3000, Leuven, Belgium
| | - Franky Bossuyt
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel, Pleinlaan 2, 1050, Brussels, Belgium
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Rancilhac L, Irisarri I, Angelini C, Arntzen JW, Babik W, Bossuyt F, Künzel S, Lüddecke T, Pasmans F, Sanchez E, Weisrock D, Veith M, Wielstra B, Steinfartz S, Hofreiter M, Philippe H, Vences M. Phylotranscriptomic evidence for pervasive ancient hybridization among Old World salamanders. Mol Phylogenet Evol 2020; 155:106967. [PMID: 33031928 DOI: 10.1016/j.ympev.2020.106967] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 07/09/2020] [Accepted: 09/28/2020] [Indexed: 11/18/2022]
Abstract
Hybridization can leave genealogical signatures in an organism's genome, originating from the parental lineages and persisting over time. This potentially confounds phylogenetic inference methods that aim to represent evolution as a strictly bifurcating tree. We apply a phylotranscriptomic approach to study the evolutionary history of, and test for inter-lineage introgression in the Salamandridae, a Holarctic salamanders group of interest in studies of toxicity and aposematism, courtship behavior, and molecular evolution. Although the relationships between the 21 currently recognized salamandrid genera have been the subject of numerous molecular phylogenetic studies, some branches have remained controversial and sometimes affected by discordances between mitochondrial vs. nuclear trees. To resolve the phylogeny of this family, and understand the source of mito-nuclear discordance, we generated new transcriptomic (RNAseq) data for 20 salamandrids and used these along with published data, including 28 mitochondrial genomes, to obtain a comprehensive nuclear and mitochondrial perspective on salamandrid evolution. Our final phylotranscriptomic data set included 5455 gene alignments for 40 species representing 17 of the 21 salamandrid genera. Using concatenation and species-tree phylogenetic methods, we find (1) Salamandrina sister to the clade of the "True Salamanders" (consisting of Chioglossa, Mertensiella, Lyciasalamandra, and Salamandra), (2) Ichthyosaura sister to the Near Eastern genera Neurergus and Ommatotriton, (3) Triturus sister to Lissotriton, and (4) Cynops paraphyletic with respect to Paramesotriton and Pachytriton. Combining introgression tests and phylogenetic networks, we find evidence for introgression among taxa within the clades of "Modern Asian Newts" and "Modern European Newts". However, we could not unambiguously identify the number, position, and direction of introgressive events. Combining evidence from nuclear gene analysis with the observed mito-nuclear phylogenetic discordances, we hypothesize a scenario with hybridization and mitochondrial capture among ancestral lineages of (1) Lissotriton into Ichthyosaura and (2) Triturus into Calotriton, plus introgression of nuclear genes from Triturus into Lissotriton. Furthermore, both mitochondrial capture and nuclear introgression may have occurred among lineages assigned to Cynops. More comprehensive genomic data will, in the future, allow testing this against alternative scenarios involving hybridization with other, extinct lineages of newts.
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Affiliation(s)
- Loïs Rancilhac
- Zoological Institute, Technische Universität Braunschweig, Mendelssohnstr. 4, 38106 Braunschweig, Germany.
| | - Iker Irisarri
- Department of Biodiversity and Evolutionary Biology, Museo Nacional de Ciencias Naturales, José Gutiérrez Abascal 2, 28006 Madrid, Spain
| | | | - Jan W Arntzen
- Naturalis Biodiversity Center, 2300 RA Leiden, the Netherlands
| | - Wiesław Babik
- Institute of Environmental Sciences, Jagiellonian University, ul. Gronostajowa 7, 30-387 Kraków, Poland
| | - Franky Bossuyt
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels Belgium
| | - Sven Künzel
- Max Planck Institute for Evolutionary Biology, 24306 Plön, Germany
| | - Tim Lüddecke
- Department of Bioresources, Fraunhofer Institute for Molecular Biology and Applied Ecology, Winchesterstr. 2, 35394 Gießen, Germany; LOEWE Centre for Translational Biodiversity Genomics (LOEWE-TBG), Senckenberganlage 25, 60325 Frankfurt, Germany
| | - Frank Pasmans
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium
| | - Eugenia Sanchez
- Zoological Institute, Technische Universität Braunschweig, Mendelssohnstr. 4, 38106 Braunschweig, Germany; Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - David Weisrock
- Department of Biology, University of Kentucky, Lexington, KY 40506, USA
| | - Michael Veith
- Biogeography Department, Trier University, 54286 Trier, Germany
| | - Ben Wielstra
- Institute of Biology Leiden, Leiden University, 2300 RA Leiden, the Netherlands
| | - Sebastian Steinfartz
- Institute of Biology, Molecular Evolution and Systematics of Animals, University of Leipzig, Talstrasse 33, 04103, Leipzig, Germany
| | - Michael Hofreiter
- Faculty of Mathematics and Natural Sciences, Institute for Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany
| | - Hervé Philippe
- Centre for Biodiversity Theory and Modelling, UMR CNRS 5321, Station of Theoretical and Experimental Ecology, 2 route du CNRS, 09200 Moulis, France
| | - Miguel Vences
- Zoological Institute, Technische Universität Braunschweig, Mendelssohnstr. 4, 38106 Braunschweig, Germany
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Bossuyt F, Schulte LM, Maex M, Janssenswillen S, Novikova PY, Biju SD, Van de Peer Y, Matthijs S, Roelants K, Martel A, Van Bocxlaer I. Multiple Independent Recruitment of Sodefrin Precursor-Like Factors in Anuran Sexually Dimorphic Glands. Mol Biol Evol 2020; 36:1921-1930. [PMID: 31238339 DOI: 10.1093/molbev/msz115] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Chemical signaling in animals often plays a central role in eliciting a variety of responses during reproductive interactions between males and females. One of the best-known vertebrate courtship pheromone systems is sodefrin precursor-like factors (SPFs), a family of two-domain three-finger proteins with a female-receptivity enhancing function, currently only known from salamanders. The oldest divergence between active components in a single salamander species dates back to the Late Paleozoic, indicating that these proteins potentially gained a pheromone function earlier in amphibian evolution. Here, we combined whole transcriptome sequencing, proteomics, histology, and molecular phylogenetics in a comparative approach to investigate SPF occurrence in male breeding glands across the evolutionary tree of anurans (frogs and toads). Our study shows that multiple families of both terrestrially and aquatically reproducing frogs have substantially increased expression levels of SPFs in male breeding glands. This suggests that multiple anuran lineages make use of SPFs to complement acoustic and visual sexual signaling during courtship. Comparative analyses show that anurans independently recruited these proteins each time the gland location on the male's body allowed efficient transmission of the secretion to the female's nares.
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Affiliation(s)
- Franky Bossuyt
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel, Brussels, Belgium
| | - Lisa M Schulte
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel, Brussels, Belgium.,Department of Wildlife-/Zoo-Animal-Biology and Systematics, Faculty of Biological Sciences, Goethe University Frankfurt, Frankfurt/Main, Germany
| | - Margo Maex
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel, Brussels, Belgium
| | - Sunita Janssenswillen
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel, Brussels, Belgium
| | - Polina Yu Novikova
- Department of Plant Biotechnology and Bioinformatics, Center for Plant Systems Biology, Ghent University, Ghent, Belgium
| | - S D Biju
- Systematics Lab, Department of Environmental Studies, University of Delhi, Delhi, India
| | - Yves Van de Peer
- Department of Plant Biotechnology and Bioinformatics, Center for Plant Systems Biology, Ghent University, Ghent, Belgium
| | - Severine Matthijs
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel, Brussels, Belgium
| | - Kim Roelants
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel, Brussels, Belgium
| | - An Martel
- Wildlife Health Ghent, Department of Pathology, Bacteriology, and Avian Diseases, Ghent University, Merelbeke, Belgium
| | - Ines Van Bocxlaer
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel, Brussels, Belgium
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Maex M, Treer D, De Greve H, Proost P, Van Bocxlaer I, Bossuyt F. Exaptation as a Mechanism for Functional Reinforcement of an Animal Pheromone System. Curr Biol 2018; 28:2955-2960.e5. [DOI: 10.1016/j.cub.2018.06.074] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 06/27/2018] [Accepted: 06/28/2018] [Indexed: 10/28/2022]
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Treer D, Maex M, Van Bocxlaer I, Proost P, Bossuyt F. Divergence of species-specific protein sex pheromone blends in two related, nonhybridizing newts (Salamandridae). Mol Ecol 2017; 27:508-519. [PMID: 29087032 DOI: 10.1111/mec.14398] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [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: 05/14/2017] [Revised: 08/17/2017] [Accepted: 08/24/2017] [Indexed: 12/01/2022]
Abstract
In animals that use chemical communication during courtship and reproduction, speciation is often associated with divergence of their sex pheromones. In multicomponent pheromone systems, divergence can be obtained either by adding or deleting components, or by altering the relative contribution of individual components to the mixture. Protein pheromone systems can additionally evolve by amino acid sequence divergence to produce pheromones with a species-specific effect. The sodefrin precursor-like factor (SPF) pheromone system, a blend of proteins that essentially enhances receptivity in salamanders, has had a long and dynamic evolution of gene duplications, but the mechanisms that govern interspecific divergence and the role they play in reproductive isolation remain elusive. Here, we use transcriptomics and proteomics to characterize the SPF protein repertoire of the alpine newt (Ichthyosaura alpestris), and compare it to the previously identified repertoire of SPF proteins of the palmate newt (Lissotriton helveticus), a related but nonhybridizing species. Subsequent phylogenetic analyses indicate that, despite the availability of multiple SPF gene copies, both species predominantly express the same subset of orthologs. Our study demonstrates that species specificity in the SPF protein pheromone system can be established by gradual sequence divergence of the same set of proteins alone.
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Affiliation(s)
- Dag Treer
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Margo Maex
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Ines Van Bocxlaer
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Paul Proost
- Laboratory of Molecular Immunology, Department of Microbiology and Immunology, Rega Institute, Katholieke Universiteit Leuven (K.U. Leuven), Leuven, Belgium
| | - Franky Bossuyt
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Brussels, Belgium
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Galle S, Derave W, Bossuyt F, Calders P, Malcolm P, De Clercq D. Exoskeleton plantarflexion assistance for elderly. Gait Posture 2017; 52:183-188. [PMID: 27915222 DOI: 10.1016/j.gaitpost.2016.11.040] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [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: 05/27/2015] [Revised: 09/20/2016] [Accepted: 11/25/2016] [Indexed: 02/02/2023]
Abstract
Elderly are confronted with reduced physical capabilities and increased metabolic energy cost of walking. Exoskeletons that assist walking have the potential to restore walking capacity by reducing the metabolic cost of walking. However, it is unclear if current exoskeletons can reduce energy cost in elderly. Our goal was to study the effect of an exoskeleton that assists plantarflexion during push-off on the metabolic energy cost of walking in physically active and healthy elderly. Seven elderly (age 69.3±3.5y) walked on treadmill (1.11ms2) with normal shoes and with the exoskeleton both powered (with assistance) and powered-off (without assistance). After 20min of habituation on a prior day and 5min on the test day, subjects were able to walk with the exoskeleton and assistance of the exoskeleton resulted in a reduction in metabolic cost of 12% versus walking with the exoskeleton powered-off. Walking with the exoskeleton was perceived less fatiguing for the muscles compared to normal walking. Assistance resulted in a statistically nonsignificant reduction in metabolic cost of 4% versus walking with normal shoes, likely due to the penalty of wearing the exoskeleton powered-off. Also, exoskeleton mechanical power was relatively low compared to previously identified optimal assistance magnitude in young adults. Future exoskeleton research should focus on further optimizing exoskeleton assistance for specific populations and on considerate integration of exoskeletons in rehabilitation or in daily life. As such, exoskeletons should allow people to walk longer or faster than without assistance and could result in an increase in physical activity and resulting health benefits.
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Affiliation(s)
- S Galle
- Department of Movement and Sport Sciences, Ghent University, Watersportlaan 2, B-9000 Ghent, Belgium.
| | - W Derave
- Department of Movement and Sport Sciences, Ghent University, Watersportlaan 2, B-9000 Ghent, Belgium.
| | - F Bossuyt
- Department of Movement and Sport Sciences, Ghent University, Watersportlaan 2, B-9000 Ghent, Belgium.
| | - P Calders
- Department of Physical Therapy and Motor Rehabilitation, De Pintelaan 185, B-9000 Ghent, Belgium.
| | - P Malcolm
- Department of Movement and Sport Sciences, Ghent University, Watersportlaan 2, B-9000 Ghent, Belgium; Department of Biomechanics, University of Nebraska at Omaha, Omaha, NE, 68182, United States.
| | - D De Clercq
- Department of Movement and Sport Sciences, Ghent University, Watersportlaan 2, B-9000 Ghent, Belgium.
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10
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Van Bocxlaer I, Maex M, Treer D, Janssenswillen S, Janssens R, Vandebergh W, Proost P, Bossuyt F. Beyond sodefrin: evidence for a multi-component pheromone system in the model newt Cynops pyrrhogaster (Salamandridae). Sci Rep 2016; 6:21880. [PMID: 26935790 PMCID: PMC4776240 DOI: 10.1038/srep21880] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 01/18/2016] [Indexed: 11/09/2022] Open
Abstract
Sodefrin, a decapeptide isolated from the male dorsal gland of the Japanese fire belly newt Cynops pyrrhogaster, was the first peptide pheromone identified from a vertebrate. The fire belly salamander and sodefrin have become a model for sex pheromone investigation in aquatically courting salamanders ever since. Subsequent studies in other salamanders identified SPF protein courtship pheromones of around 20 kDa belonging to the same gene-family. Although transcripts of these proteins could be PCR-amplified in Cynops, it is currently unknown whether they effectively use full-length SPF pheromones next to sodefrin. Here we combined transcriptomics, proteomics and phylogenetics to investigate SPF pheromone use in Cynops pyrrhogaster. Our data show that not sodefrin transcripts, but multiple SPF transcripts make up the majority of the expression profile in the dorsal gland of this newt. Proteome analyses of water in which a male has been courting confirm that this protein blend is effectively secreted and tail-fanned to the female. By combining phylogenetics and expression data, we show that independent evolutionary lineages of these SPF’s were already expressed in ancestral Cynops species before the origin of sodefrin. Extant Cynops species continue to use this multi-component pheromone system, consisting of various proteins in addition to a lineage-specific peptide.
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Affiliation(s)
- Ines Van Bocxlaer
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050 Brussels, Belgium
| | - Margo Maex
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050 Brussels, Belgium
| | - Dag Treer
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050 Brussels, Belgium
| | - Sunita Janssenswillen
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050 Brussels, Belgium
| | - Rik Janssens
- Laboratory of Molecular Immunology, Department of Microbiology and Immunology, KU Leuven - University of Leuven, Minderbroedersstraat 10 - box 1030, B-3000 Leuven, Belgium
| | - Wim Vandebergh
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050 Brussels, Belgium
| | - Paul Proost
- Laboratory of Molecular Immunology, Department of Microbiology and Immunology, KU Leuven - University of Leuven, Minderbroedersstraat 10 - box 1030, B-3000 Leuven, Belgium
| | - Franky Bossuyt
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050 Brussels, Belgium
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Abstract
Pheromones are an important component of sexual communication in courting salamanders, but the number of species in which their use has been demonstrated with behavioral evidence remains limited. Here we developed a behavioral assay for demonstrating courtship pheromone use in the aquatically courting Iberian ribbed newt Pleurodeles waltl. By performing an in-depth study of the courtship behavior, we show that females invariably open their cloaca (cloacal gaping) before engaging in pinwheel behavior, the circling movement that is the prelude to spermatophore uptake. In contrast, cloacal gaping was not observed in failed courtships, where females escaped or displayed thanatosis. Since gaping mainly occurred during male amplexus and cloacal imposition, which is the obvious period of pheromone transfer, we next investigated whether male courtship water (i.e., water holding courtship pheromones) alone was able to induce this reaction in females. These tests showed that courtship water induced cloacal gaping significantly more than water, even in the absence of a male. Cloacal gaping thus provides a simple and robust test for demonstrating courtship pheromone use in the Iberian ribbed newt. Since opening the cloaca is an essential prerequisite for spermatophore pick-up in all internally fertilizing salamanders, we hypothesize that variations on this assay will also be useful in several other species.
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Affiliation(s)
| | - Franky Bossuyt
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit, Brussel, Belgium
- * E-mail:
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Van Bocxlaer I, Treer D, Maex M, Vandebergh W, Janssenswillen S, Stegen G, Kok P, Willaert B, Matthijs S, Martens E, Mortier A, de Greve H, Proost P, Bossuyt F. Side-by-side secretion of Late Palaeozoic diverged courtship pheromones in an aquatic salamander. Proc Biol Sci 2015; 282:20142960. [PMID: 25694622 PMCID: PMC4345460 DOI: 10.1098/rspb.2014.2960] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [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
Males of the advanced salamanders (Salamandroidea) attain internal fertilization without a copulatory organ by depositing a spermatophore on the substrate in the environment, which females subsequently take up with their cloaca. The aquatically reproducing modern Eurasian newts (Salamandridae) have taken this to extremes, because most species do not display close physical contact during courtship, but instead largely rely on females following the male track at spermatophore deposition. Although pheromones have been widely assumed to represent an important aspect of male courtship, molecules able to induce the female following behaviour that is the prelude for successful insemination have not yet been identified. Here, we show that uncleaved sodefrin precursor-like factor (SPF) protein pheromones are sufficient to elicit such behaviour in female palmate newts (Lissotriton helveticus). Combined transcriptomic and proteomic evidence shows that males simultaneously tail-fan multiple ca 20 kDa glycosylated SPF proteins during courtship. Notably, molecular dating estimates show that the diversification of these proteins already started in the late Palaeozoic, about 300 million years ago. Our study thus not only extends the use of uncleaved SPF proteins outside terrestrially reproducing plethodontid salamanders, but also reveals one of the oldest vertebrate pheromone systems.
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Affiliation(s)
- Ines Van Bocxlaer
- Amphibian Evolution Laboratory, Biology Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium
| | - Dag Treer
- Amphibian Evolution Laboratory, Biology Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium
| | - Margo Maex
- Amphibian Evolution Laboratory, Biology Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium
| | - Wim Vandebergh
- Amphibian Evolution Laboratory, Biology Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium
| | - Sunita Janssenswillen
- Amphibian Evolution Laboratory, Biology Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium
| | - Gwij Stegen
- Amphibian Evolution Laboratory, Biology Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium
| | - Philippe Kok
- Amphibian Evolution Laboratory, Biology Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium
| | - Bert Willaert
- Amphibian Evolution Laboratory, Biology Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium
| | - Severine Matthijs
- Amphibian Evolution Laboratory, Biology Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium
| | - Erik Martens
- Laboratory of Immunobiology, Department of Microbiology and Immunology, Rega Institute, Katholieke Universiteit Leuven (K.U. Leuven), Minderbroedersstraat 10-Box 1030, 3000 Leuven, Belgium
| | - Anneleen Mortier
- Laboratory of Molecular Immunology, Department of Microbiology and Immunology, Rega Institute, Katholieke Universiteit Leuven (K.U. Leuven), Minderbroedersstraat 10-Box 1030, 3000 Leuven, Belgium
| | - Henri de Greve
- Structural and Molecular Microbiology, Structural Biology Research Centre, VIB, Pleinlaan 2, 1050 Brussels, Belgium Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
| | - Paul Proost
- Laboratory of Molecular Immunology, Department of Microbiology and Immunology, Rega Institute, Katholieke Universiteit Leuven (K.U. Leuven), Minderbroedersstraat 10-Box 1030, 3000 Leuven, Belgium
| | - Franky Bossuyt
- Amphibian Evolution Laboratory, Biology Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium
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Bossuyt F, García-Pinillos F, Raja Azidin R, Vanrenterghem J, Robinson M. The Utility of a High-intensity Exercise Protocol to Prospectively Assess ACL Injury Risk. Int J Sports Med 2015; 37:125-33. [DOI: 10.1055/s-0035-1555930] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- F. Bossuyt
- Research Institute of Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | | | - R. Raja Azidin
- Research Institute of Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - J. Vanrenterghem
- Research Institute for Sport and Exercise, Liverpool John Moores University, Liverpool, United Kingdom
| | - M. Robinson
- Sport Science, Liverpool John Moores University, Liverpool, United Kingdom
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Janssenswillen S, Willaert B, Treer D, Vandebergh W, Bossuyt F, Van Bocxlaer I. High pheromone diversity in the male cheek gland of the red-spotted newt Notophthalmus viridescens (Salamandridae). BMC Evol Biol 2015; 15:54. [PMID: 25888438 PMCID: PMC4379952 DOI: 10.1186/s12862-015-0333-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 03/09/2015] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Male salamanders (Urodela) often make use of pheromones that are produced in sexually dimorphic glands to persuade the female into courtship and mating. The mental gland of lungless salamanders (Plethodontidae) and dorsal cloacal glands (or abdominal glands) of newts (Salamandridae) have been particularly well studied in that respect. In both families, sodefrin precursor-like factor (SPF) proteins have been identified as major components of the courtship pheromone system. However, similar to plethodontids, some newts also make use of subtle head glands during courtship, but few pheromones have been characterized from such structures. Males of red-spotted newts (Notophthalmus viridescens, Salamandridae) have both cloacal and cheek (genial) glands, and are known to apply secretions to the female's nose by both tail-fanning and cheek-rubbing. Here we combined transcriptomic and phylogenetic analyses to investigate the presence, diversity and evolution of SPF proteins in the cloacal and cheek glands of this species. RESULTS Our analyses indicate that the cheek glands of male N. viridescens produce a similar amount and diversity of SPF isoforms as the cloacal glands in this species. Expression in other tissues was much lower, suggesting that both male-specific courtship glands secrete SPF pheromones during courtship. Our phylogenetic analyses show that N. viridescens expresses a combination of isoforms that stem from four highly diverged evolutionary lineages of SPF variants, that together form a basis for the broad diversity of SPF precursors in the breeding glands. CONCLUSIONS The similar SPF expression of cheek and cloacal glands suggests that this protein family is used for pheromone signalling through cheek rubbing in the red-spotted newt. Since several male salamandrids in other genera have comparable head glands, SPF application via other glands than the cloacal glands may be more widespread than currently appreciated in salamandrids.
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Affiliation(s)
- Sunita Janssenswillen
- Biology Department, Amphibian Evolution Lab, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050, Brussels, Belgium.
| | - Bert Willaert
- Biology Department, Amphibian Evolution Lab, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050, Brussels, Belgium.
| | - Dag Treer
- Biology Department, Amphibian Evolution Lab, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050, Brussels, Belgium.
| | - Wim Vandebergh
- Biology Department, Amphibian Evolution Lab, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050, Brussels, Belgium.
| | - Franky Bossuyt
- Biology Department, Amphibian Evolution Lab, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050, Brussels, Belgium.
| | - Ines Van Bocxlaer
- Biology Department, Amphibian Evolution Lab, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050, Brussels, Belgium.
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15
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Janssenswillen S, Vandebergh W, Treer D, Willaert B, Maex M, Van Bocxlaer I, Bossuyt F. Origin and diversification of a salamander sex pheromone system. Mol Biol Evol 2014; 32:472-80. [PMID: 25415963 DOI: 10.1093/molbev/msu316] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Sex pheromones form an important facet of reproductive strategies in many organisms throughout the Animal Kingdom. One of the oldest known sex pheromones in vertebrates are proteins of the Sodefrin Precursor-like Factor (SPF) system, which already had a courtship function in early salamanders. The subsequent evolution of salamanders is characterized by a diversification in courtship and reproduction, but little is known on how the SPF pheromone system diversified in relation to changing courtship strategies. Here, we combined transcriptomic, genomic, and phylogenetic analyses to investigate the evolution of the SPF pheromone system in nine salamandrid species with distinct courtship displays. First, we show that SPF originated from vertebrate three-finger proteins and diversified through multiple gene duplications in salamanders, while remaining a single copy in frogs. Next, we demonstrate that tail-fanning newts have retained a high phylogenetic diversity of SPFs, whereas loss of tail-fanning has been associated with a reduced importance or loss of SPF expression in the cloacal region. Finally, we show that the attractant decapeptide sodefrin is cleaved from larger SPF precursors that originated by a 62 bp insertion and consequent frameshift in an ancestral Cynops lineage. This led to the birth of a new decapeptide that rapidly evolved a pheromone function independently from uncleaved proteins.
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Affiliation(s)
- Sunita Janssenswillen
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Wim Vandebergh
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Dag Treer
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Bert Willaert
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Margo Maex
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Ines Van Bocxlaer
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Franky Bossuyt
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel (VUB), Brussels, Belgium
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Martel A, Blooi M, Adriaensen C, Van Rooij P, Beukema W, Fisher MC, Farrer RA, Schmidt BR, Tobler U, Goka K, Lips KR, Muletz C, Zamudio KR, Bosch J, Lötters S, Wombwell E, Garner TWJ, Cunningham AA, Spitzen-van der Sluijs A, Salvidio S, Ducatelle R, Nishikawa K, Nguyen TT, Kolby JE, Van Bocxlaer I, Bossuyt F, Pasmans F. Wildlife disease. Recent introduction of a chytrid fungus endangers Western Palearctic salamanders. Science 2014; 346:630-1. [PMID: 25359973 DOI: 10.1126/science.1258268] [Citation(s) in RCA: 299] [Impact Index Per Article: 29.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Emerging infectious diseases are reducing biodiversity on a global scale. Recently, the emergence of the chytrid fungus Batrachochytrium salamandrivorans resulted in rapid declines in populations of European fire salamanders. Here, we screened more than 5000 amphibians from across four continents and combined experimental assessment of pathogenicity with phylogenetic methods to estimate the threat that this infection poses to amphibian diversity. Results show that B. salamandrivorans is restricted to, but highly pathogenic for, salamanders and newts (Urodela). The pathogen likely originated and remained in coexistence with a clade of salamander hosts for millions of years in Asia. As a result of globalization and lack of biosecurity, it has recently been introduced into naïve European amphibian populations, where it is currently causing biodiversity loss.
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Affiliation(s)
- A Martel
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820 Merelbeke, Belgium.
| | - M Blooi
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820 Merelbeke, Belgium. Centre for Research and Conservation, Royal Zoological Society of Antwerp, Koningin Astridplein 26, Antwerp, Belgium
| | - C Adriaensen
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820 Merelbeke, Belgium
| | - P Van Rooij
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820 Merelbeke, Belgium
| | - W Beukema
- CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos da Universidade do Porto, Instituto de Ciências Agrárias de Vairão, Rua Padre Armando Quintas, Vairão, Portugal
| | - M C Fisher
- Department of Infectious Disease Epidemiology, Imperial College London, Norfolk Place, London W2 1PG, UK
| | - R A Farrer
- Genome Sequencing and Analysis Program, The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - B R Schmidt
- Koordinationsstelle für amphibien- und reptilienschutz in der Schweiz (KARCH), Passage Maximilien-de-Meuron 6, 2000 Neuchâtel, Switzerland. Institut für Evolutionsbiologie und Umweltwissenschaften, Universität Zürich. Winterthurerstrasse 190, 8057 Zürich, Switzerland
| | - U Tobler
- Koordinationsstelle für amphibien- und reptilienschutz in der Schweiz (KARCH), Passage Maximilien-de-Meuron 6, 2000 Neuchâtel, Switzerland. Institut für Evolutionsbiologie und Umweltwissenschaften, Universität Zürich. Winterthurerstrasse 190, 8057 Zürich, Switzerland
| | - K Goka
- Invasive Alien Species Research Team, National Institute for Environment Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan
| | - K R Lips
- Department of Biology, University of Maryland, College Park, MD 20742, USA
| | - C Muletz
- Department of Biology, University of Maryland, College Park, MD 20742, USA
| | - K R Zamudio
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY 14853, USA
| | - J Bosch
- Museo Nacional de Ciencias Naturales, Consejo Superior de Investigaciones cientificas (CSIC), José Gutiérrez Abascal 2, 28006 Madrid, Spain
| | - S Lötters
- Biogeography Department, Trier University, 54286 Trier, Germany
| | - E Wombwell
- Durrell Institute of Conservation and Ecology, University of Kent, Kent CT2 7NR, UK. Institute of Zoology, Zoological Society of London, London NW1 4RY, UK
| | - T W J Garner
- Institute of Zoology, Zoological Society of London, London NW1 4RY, UK
| | - A A Cunningham
- Institute of Zoology, Zoological Society of London, London NW1 4RY, UK
| | - A Spitzen-van der Sluijs
- Reptile, Amphibian and Fish Conservation the Netherlands (RAVON), Post Office Box 1413, 6501 BK Nijmegen, Netherlands
| | - S Salvidio
- Department of Earth Science, Environmental and Life (Di.S.T.A.V.), University of Genova, Corso Europa 26, I-16132 Genova, Italy
| | - R Ducatelle
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820 Merelbeke, Belgium
| | - K Nishikawa
- Graduate School of Human and Environmental Studies, Kyoto University, Yoshida Nihonmatsu-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - T T Nguyen
- Vietnam National Museum of Nature, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Cau Giay, Hanoi, Vietnam
| | - J E Kolby
- James Cook University, One Health Research Group, School of Public Health, Tropical Medicine and Rehabilitation Sciences, Townsville, Queensland, Australia
| | - I Van Bocxlaer
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
| | - F Bossuyt
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
| | - F Pasmans
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820 Merelbeke, Belgium
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Matthijs S, Ye L, Stijlemans B, Cornelis P, Bossuyt F, Roelants K. Low structural variation in the host-defense peptide repertoire of the dwarf clawed frog Hymenochirus boettgeri (Pipidae). PLoS One 2014; 9:e86339. [PMID: 24466037 PMCID: PMC3899252 DOI: 10.1371/journal.pone.0086339] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Accepted: 12/06/2013] [Indexed: 02/05/2023] Open
Abstract
THE skin secretion of many amphibians contains peptides that are able to kill a broad range of microorganisms (antimicrobial peptides: AMPs) and potentially play a role in innate immune defense. Similar to the toxin arsenals of various animals, amphibian AMP repertoires typically show major structural variation, and previous studies have suggested that this may be the result of diversifying selection in adaptation to a diverse spectrum of pathogens. Here we report on transcriptome analyses that indicate a very different pattern in the dwarf clawed frog H. boettgeri. Our analyses reveal a diverse set of transcripts containing two to six tandem repeats, together encoding 14 distinct peptides. Five of these have recently been identified as AMPs, while three more are shown here to potently inhibit the growth of gram-negative bacteria, including multi-drug resistant strains of the medically important Pseudomonas aeruginosa. Although the number of predicted peptides is similar to the numbers of related AMPs in Xenopus and Silurana frog species, they show significantly lower structural variation. Selection analyses confirm that, in contrast to the AMPs of other amphibians, the H. boettgeri peptides did not evolve under diversifying selection. Instead, the low sequence variation among tandem repeats resulted from purifying selection, recent duplication and/or concerted gene evolution. Our study demonstrates that defense peptide repertoires of closely related taxa, after diverging from each other, may evolve under differential selective regimes, leading to contrasting patterns of structural diversity.
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Affiliation(s)
- Severine Matthijs
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel, Brussels, Belgium
| | - Lumeng Ye
- Department of Bioengineering Sciences, Research Group of Microbiology and Vlaams Instituut voor Biotechnologie, Vrije Universiteit Brussel, Brussels, Belgium
| | - Benoit Stijlemans
- Unit of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Brussels, Belgium
- Laboratory of Myeloid Cell Immunology, Vlaams Instituut voor Biotechnologie, Brussels, Belgium
| | - Pierre Cornelis
- Department of Bioengineering Sciences, Research Group of Microbiology and Vlaams Instituut voor Biotechnologie, Vrije Universiteit Brussel, Brussels, Belgium
| | - Franky Bossuyt
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel, Brussels, Belgium
| | - Kim Roelants
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel, Brussels, Belgium
- * E-mail:
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Yang Y, Chiesura G, Luyckx G, Vervust T, Bossuyt F, Kaufmann M, Degrieck J, Vanfleteren J. Development of a Dielectric Sensor System for the On-line Cure Monitoring of Composites. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.protcy.2014.09.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Vanfleteren J, Chtioui I, Plovie B, Yang Y, Bossuyt F, Vervust T, Dunphy S, Vandecasteele B. Arbitrarily Shaped 2.5D Circuits Using Stretchable Interconnections and Embedding in Thermoplastic Polymers. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.protcy.2014.09.073] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Martel A, Spitzen-van der Sluijs A, Blooi M, Bert W, Ducatelle R, Fisher MC, Woeltjes A, Bosman W, Chiers K, Bossuyt F, Pasmans F. Batrachochytrium salamandrivorans sp. nov. causes lethal chytridiomycosis in amphibians. Proc Natl Acad Sci U S A 2013; 110:15325-9. [PMID: 24003137 PMCID: PMC3780879 DOI: 10.1073/pnas.1307356110] [Citation(s) in RCA: 382] [Impact Index Per Article: 34.7] [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] [Indexed: 11/18/2022] Open
Abstract
The current biodiversity crisis encompasses a sixth mass extinction event affecting the entire class of amphibians. The infectious disease chytridiomycosis is considered one of the major drivers of global amphibian population decline and extinction and is thought to be caused by a single species of aquatic fungus, Batrachochytrium dendrobatidis. However, several amphibian population declines remain unexplained, among them a steep decrease in fire salamander populations (Salamandra salamandra) that has brought this species to the edge of local extinction. Here we isolated and characterized a unique chytrid fungus, Batrachochytrium salamandrivorans sp. nov., from this salamander population. This chytrid causes erosive skin disease and rapid mortality in experimentally infected fire salamanders and was present in skin lesions of salamanders found dead during the decline event. Together with the closely related B. dendrobatidis, this taxon forms a well-supported chytridiomycete clade, adapted to vertebrate hosts and highly pathogenic to amphibians. However, the lower thermal growth preference of B. salamandrivorans, compared with B. dendrobatidis, and resistance of midwife toads (Alytes obstetricans) to experimental infection with B. salamandrivorans suggest differential niche occupation of the two chytrid fungi.
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Affiliation(s)
- An Martel
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, B-9820 Merelbeke, Belgium
| | | | - Mark Blooi
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, B-9820 Merelbeke, Belgium
| | - Wim Bert
- Department of Biology, Nematology Unit, Faculty of Science, Ghent University, 9000 Ghent, Belgium
| | - Richard Ducatelle
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, B-9820 Merelbeke, Belgium
| | - Matthew C. Fisher
- Department of Infectious Disease Epidemiology, Faculty of Medicine, Imperial College London, London W2 1PG, United Kingdom; and
| | - Antonius Woeltjes
- Reptile, Amphibian and Fish Conservation The Netherlands, 6501 BK, Nijmegen, Netherlands
| | - Wilbert Bosman
- Reptile, Amphibian and Fish Conservation The Netherlands, 6501 BK, Nijmegen, Netherlands
| | - Koen Chiers
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, B-9820 Merelbeke, Belgium
| | - Franky Bossuyt
- Amphibian Evolution Lab, Biology Department, Vrije Universiteit Brussel, 1050 Brussels, Belgium
| | - Frank Pasmans
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, B-9820 Merelbeke, Belgium
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Willaert B, Bossuyt F, Janssenswillen S, Adriaens D, Baggerman G, Matthijs S, Pauwels E, Proost P, Raepsaet A, Schoofs L, Stegen G, Treer D, Van Hoorebeke L, Vandebergh W, Van Bocxlaer I. Frog nuptial pads secrete mating season-specific proteins related to salamander pheromones. ACTA ACUST UNITED AC 2013; 216:4139-43. [PMID: 23948475 DOI: 10.1242/jeb.086363] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Males of many frog species develop spiny nuptial pads with underlying glands on their thumbs during the mating period. We used 3D visualization on the European common frog Rana temporaria to show that the morphology of these glands allows the channelling of secreted molecules to the pad's surface during amplexus. Combined transcriptome and proteome analyses show that proteins of the Ly-6/uPAR family, here termed amplexins, are highly expressed in the nuptial glands during the mating season, but are totally absent outside that period. The function of amplexins remains unknown, but it is interesting to note that they share structural similarities with plethodontid modulating factors, proteins that influence courtship duration in salamanders.
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Affiliation(s)
- Bert Willaert
- Vrije Universiteit Brussel, Biology Department, Amphibian Evolution Lab, Pleinlaan 2, B-1050 Brussels, Belgium
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Vandebergh W, Maex M, Bossuyt F, Van Bocxlaer I. Recurrent functional divergence of early tetrapod keratins in amphibian toe pads and mammalian hair. Biol Lett 2013; 9:20130051. [PMID: 23485876 DOI: 10.1098/rsbl.2013.0051] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Amphibians have invaded arboreal habitats multiple times independently during their evolution. Adaptation to these habitats was nearly always accompanied by the presence or appearance of toe pads, flattened enlargements on tips of fingers and toes that provide adhesive power in these environments. The strength and elasticity of the toe pad relies on polygonal arrayed cells ending in nanoscale projections, which are densely packed with cytoskeletal proteins. Here, we characterized and determined the evolutionary origin of these proteins in the toe pad of the tree frog Hyla cinerea. We created a subtracted cDNA library enriching genes that are expressed in the toe pad, but nowhere else in the toe. Our analyses revealed five alpha keratins as main structural proteins of the amphibian toe pad. Phylogenetic analyses show that these proteins belong to different keratin lineages that originated in an early tetrapod ancestor and in mammals evolved to become the major keratin types of hair. The ancestral keratins were probably already expressed in areas that required skin reinforcement in early tetrapods, and subsequently diverged to support fundamentally different adaptive structures in amphibians and mammals.
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Affiliation(s)
- Wim Vandebergh
- Biology Department, Amphibian Evolution Lab, Vrije Universiteit Brussel, , Pleinlaan 2, Brussels 1050, Belgium.
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Treer D, Van Bocxlaer I, Matthijs S, Du Four D, Janssenswillen S, Willaert B, Bossuyt F. Love is blind: indiscriminate female mating responses to male courtship pheromones in newts (Salamandridae). PLoS One 2013; 8:e56538. [PMID: 23457580 PMCID: PMC3574087 DOI: 10.1371/journal.pone.0056538] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Accepted: 01/10/2013] [Indexed: 11/18/2022] Open
Abstract
Internal fertilization without copulation or prolonged physical contact is a rare reproductive mode among vertebrates. In many newts (Salamandridae), the male deposits a spermatophore on the substrate in the water, which the female subsequently takes up with her cloaca. Because such an insemination requires intense coordination of both sexes, male newts have evolved a courtship display, essentially consisting of sending pheromones under water by tail-fanning towards their potential partner. Behavioral experiments until now mostly focused on an attractant function, i.e. showing that olfactory cues are able to bring both sexes together. However, since males start their display only after an initial contact phase, courtship pheromones are expected to have an alternative function. Here we developed a series of intraspecific and interspecific two-female experiments with alpine newt (Ichthyosaura alpestris) and palmate newt (Lissotriton helveticus) females, comparing behavior in male courtship water and control water. We show that male olfactory cues emitted during tail-fanning are pheromones that can induce all typical features of natural female mating behavior. Interestingly, females exposed to male pheromones of their own species show indiscriminate mating responses to conspecific and heterospecific females, indicating that visual cues are subordinate to olfactory cues during courtship.
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Affiliation(s)
- Dag Treer
- Amphibian Evolution Lab, Vrije Universiteit Brussel, Brussels, Belgium
| | - Ines Van Bocxlaer
- Amphibian Evolution Lab, Vrije Universiteit Brussel, Brussels, Belgium
| | - Severine Matthijs
- Amphibian Evolution Lab, Vrije Universiteit Brussel, Brussels, Belgium
| | - Dimitri Du Four
- Amphibian Evolution Lab, Vrije Universiteit Brussel, Brussels, Belgium
| | | | - Bert Willaert
- Amphibian Evolution Lab, Vrije Universiteit Brussel, Brussels, Belgium
| | - Franky Bossuyt
- Amphibian Evolution Lab, Vrije Universiteit Brussel, Brussels, Belgium
- * E-mail:
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Kamei RG, San Mauro D, Gower DJ, Van Bocxlaer I, Sherratt E, Thomas A, Babu S, Bossuyt F, Wilkinson M, Biju SD. Discovery of a new family of amphibians from northeast India with ancient links to Africa. Proc Biol Sci 2012; 279:2396-401. [PMID: 22357266 DOI: 10.1098/rspb.2012.0150] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The limbless, primarily soil-dwelling and tropical caecilian amphibians (Gymnophiona) comprise the least known order of tetrapods. On the basis of unprecedented extensive fieldwork, we report the discovery of a previously overlooked, ancient lineage and radiation of caecilians from threatened habitats in the underexplored states of northeast India. Molecular phylogenetic analyses of mitogenomic and nuclear DNA sequences, and comparative cranial anatomy indicate an unexpected sister-group relationship with the exclusively African family Herpelidae. Relaxed molecular clock analyses indicate that these lineages diverged in the Early Cretaceous, about 140 Ma. The discovery adds a major branch to the amphibian tree of life and sheds light on both the evolution and biogeography of caecilians and the biotic history of northeast India-an area generally interpreted as a gateway between biodiversity hotspots rather than a distinct biogeographic unit with its own ancient endemics. Because of its distinctive morphology, inferred age and phylogenetic relationships, we recognize the newly discovered caecilian radiation as a new family of modern amphibians.
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Affiliation(s)
- Rachunliu G Kamei
- Department of Environmental Studies, Systematics Laboratory, Centre for Environmental Management of Degraded Ecosystems, University of Delhi, Delhi, 110 007, India
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Van Bocxlaer I, Biju SD, Willaert B, Giri VB, Shouche YS, Bossuyt F. Mountain-associated clade endemism in an ancient frog family (Nyctibatrachidae) on the Indian subcontinent. Mol Phylogenet Evol 2011; 62:839-47. [PMID: 22178364 DOI: 10.1016/j.ympev.2011.11.027] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Revised: 11/17/2011] [Accepted: 11/24/2011] [Indexed: 10/14/2022]
Abstract
Night frogs (Nyctibatrachidae) form a family endemic to the Western Ghats, a hill chain along the west coast of southern India. Extant members of this family are descendants of a lineage that originated on the subcontinent during its longtime isolation in the Late Cretaceous. Because the evolutionary history of Nyctibatrachidae has always been tightly connected to the subcontinent, these tropically-adapted frogs are an ideal group for studying how patterns of endemism originated and evolved during the Cenozoic in the Western Ghats. We used a combined set of mitochondrial and nuclear DNA fragments to investigate the phylogenetic relationships of 120 ingroup specimens of all known species of Nyctibatrachidae. Our analyses indicate that, although this family had an early origin on the Indian subcontinent, the early diversification of extant nyctibatrachids happened only in the Eocene. Biogeographic analyses show that dispersal across the Palghat gap and Shencottah gap was limited, which led to clade endemism within mountain ranges of the Western Ghats. It is likely that multiple biota have been affected simultaneously by these prominent geographical barriers. Our study therefore further highlights the importance of considering the Western Ghats-Sri Lanka biodiversity hotspot as an assemblage of distinct mountain regions, each containing endemism and deserving attention in future conservation planning.
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Affiliation(s)
- Ines Van Bocxlaer
- Biology Department, Amphibian Evolution Lab, Unit of Ecology & Systematics, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium.
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Vandebergh W, Bossuyt F. Radiation and Functional Diversification of Alpha Keratins during Early Vertebrate Evolution. Mol Biol Evol 2011; 29:995-1004. [DOI: 10.1093/molbev/msr269] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
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Abstract
Anurans (frogs and toads) are unique among land vertebrates in possessing a free-living larval stage that, parallel to adult frogs, diversified into an impressive range of ecomorphs. The tempo and mode at which tadpole morphology evolved through anuran history as well as its relationship to lineage diversification remain elusive. We used a molecular phylogenetic framework to examine patterns of morphological evolution in tadpoles in light of observed episodes of accelerated lineage diversification. Our reconstructions show that the expansion of tadpole morphospace during the basal anuran radiation in the Triassic/Early Jurassic was unparalleled by the basal neobatrachian radiation in the Late Jurassic/Early Cretaceous or any subsequent radiation in the Late Cretaceous/Early Tertiary. Comparative analyses of radiation episodes indicate that the slowdown of morphospace expansion was caused not only by a drop in evolutionary rate after the basal anuran radiation but also by an overall increase in homoplasy in the characters that did evolve during later radiations. The overlapping sets of evolving characters among more recent radiations may have enhanced tadpole diversity by creating unique combinations of homoplastic traits, but the lack of innovative character changes prevented the exploration of fundamental regions in morphospace. These complex patterns transcend the four traditionally recognized tadpole morphotypes and apply to most tissue types and body parts.
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Affiliation(s)
- Kim Roelants
- Unit of Ecology and Systematics, Vrije Universiteit Brussel, 1050 Brussels, Belgium.
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Mannaert A, Amemiya CT, Bossuyt F. Comparative analyses of vertebrate posterior HoxD clusters reveal atypical cluster architecture in the caecilian Typhlonectes natans. BMC Genomics 2010; 11:658. [PMID: 21106068 PMCID: PMC3091776 DOI: 10.1186/1471-2164-11-658] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2010] [Accepted: 11/24/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The posterior genes of the HoxD cluster play a crucial role in the patterning of the tetrapod limb. This region is under the control of a global, long-range enhancer that is present in all vertebrates. Variation in limb types, as is the case in amphibians, can probably not only be attributed to variation in Hox genes, but is likely to be the product of differences in gene regulation. With a collection of vertebrate genome sequences available today, we used a comparative genomics approach to study the posterior HoxD cluster of amphibians. A frog and a caecilian were included in the study to compare coding sequences as well as to determine the gain and loss of putative regulatory sequences. RESULTS We sequenced the posterior end of the HoxD cluster of a caecilian and performed comparative analyses of this region using HoxD clusters of other vertebrates. We determined the presence of conserved non-coding sequences and traced gains and losses of these footprints during vertebrate evolution, with particular focus on amphibians. We found that the caecilian HoxD cluster is almost three times larger than its mammalian counterpart. This enlargement is accompanied with the loss of one gene and the accumulation of repeats in that area. A similar phenomenon was observed in the coelacanth, where a different gene was lost and expansion of the area where the gene was lost has occurred. At least one phylogenetic footprint present in all vertebrates was lost in amphibians. This conserved region is a known regulatory element and functions as a boundary element in neural tissue to prevent expression of Hoxd genes. CONCLUSION The posterior part of the HoxD cluster of Typhlonectes natans is among the largest known today. The loss of Hoxd-12 and the expansion of the intergenic region may exert an influence on the limb enhancer, by having to bypass a distance seven times that of regular HoxD clusters. Whether or not there is a correlation with the loss of limbs remains to be investigated. These results, together with data on other vertebrates show that the tetrapod Hox clusters are more variable than previously thought.
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Affiliation(s)
- An Mannaert
- Biology Department, ECOL, Amphibian Evolution Lab, Vrije Universiteit Brussel, Brussels, Belgium
| | - Chris T Amemiya
- Benaroya Research Institute at Virginia Mason and University of Washington, Seattle, USA
| | - Franky Bossuyt
- Biology Department, ECOL, Amphibian Evolution Lab, Vrije Universiteit Brussel, Brussels, Belgium
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Van Bocxlaer I, Loader SP, Roelants K, Biju SD, Menegon M, Bossuyt F. Gradual Adaptation Toward a Range-Expansion Phenotype Initiated the Global Radiation of Toads. Science 2010; 327:679-82. [DOI: 10.1126/science.1181707] [Citation(s) in RCA: 173] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Roelants K, Fry BG, Norman JA, Clynen E, Schoofs L, Bossuyt F. Identical Skin Toxins by Convergent Molecular Adaptation in Frogs. Curr Biol 2010; 20:125-30. [DOI: 10.1016/j.cub.2009.11.015] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2009] [Revised: 11/04/2009] [Accepted: 11/05/2009] [Indexed: 10/20/2022]
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Biju S, Van Bocxlaer I, Giri VB, Loader SP, Bossuyt F. Two new endemic genera and a new species of toad (Anura: Bufonidae) from the Western Ghats of India. BMC Res Notes 2009; 2:241. [PMID: 19968866 PMCID: PMC2797014 DOI: 10.1186/1756-0500-2-241] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2009] [Accepted: 12/07/2009] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Bufonidae are a large family of toads with a subcosmopolitan distribution. Recent molecular phylogenetic analyses have revealed a radiation of toads (Adenominae) with distinct adult and larval ecomorphs on the Southern parts of the Indian subcontinent. The Indian torrential species "Ansonia" ornata has a basal position in this clade and does not group with South-East Asian Ansonia. Additionally, the nested position of "Bufo" koynayensis and an undescribed sister species, and their distinct ecologies including a non-typical egg-laying strategy within bufonids, support the recognition of a second distinct genus. In this paper we describe two new genera and one new species from the Adenominae clade. FINDINGS Ansonia ornata Günther, 1876 "1875" is transferred to Ghatophryne gen. nov., a genus of torrentially adapted toads that are endemic to the Western Ghats of India. On the basis of close morphological resemblance and distribution, Ansonia rubigina Pillai and Pattabiraman, 1981 is provisionally transferred to this new genus. The Western Ghats endemic toad Bufo koynayensis Soman, 1963 is transferred to a new genus Xanthophryne gen. nov. Based on molecular and morphological evidence, we additionally describe a new species, Xanthophryne tigerinus sp. nov., from Amboli in the Western Ghats. CONCLUSION The descriptions and subsequent taxonomic changes we propose result in three genera of bufonids recognised as being endemic to the Western Ghats (Ghatophryne gen. nov., Xanthophryne gen. nov. and Pedostibes), and one to Sri Lanka (Adenomus). The spatial distribution, and arrangement of these lineages at the base of Adenominae diversification, reflects their Early Neogene isolation in the Western Ghats-Sri Lanka hotspot.
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Affiliation(s)
- Sd Biju
- Biology Department, Unit of Ecology & Systematics: Amphibian Evolution Lab, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050 Brussels, Belgium.
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Axisa F, Brosteaux D, De Leersnyder E, Bossuyt F, Vanfleteren J, Hermans B, Puers R. Biomedical Stretchable Sytems using MID Based Stretchable Electronics Technology. ACTA ACUST UNITED AC 2007; 2007:5688-91. [DOI: 10.1109/iembs.2007.4353637] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Roelants K, Gower DJ, Wilkinson M, Loader SP, Biju SD, Guillaume K, Moriau L, Bossuyt F. Global patterns of diversification in the history of modern amphibians. Proc Natl Acad Sci U S A 2007; 104:887-92. [PMID: 17213318 PMCID: PMC1783409 DOI: 10.1073/pnas.0608378104] [Citation(s) in RCA: 485] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The fossil record of modern amphibians (frogs, salamanders, and caecilians) provides no evidence for major extinction or radiation episodes throughout most of the Mesozoic and early Tertiary. However, long-term gradual diversification is difficult to reconcile with the sensitivity of present-day amphibian faunas to rapid ecological changes and the incidence of similar environmental perturbations in the past that have been associated with high turnover rates in other land vertebrates. To provide a comprehensive overview of the history of amphibian diversification, we constructed a phylogenetic timetree based on a multigene data set of 3.75 kb for 171 species. Our analyses reveal several episodes of accelerated amphibian diversification, which do not fit models of gradual lineage accumulation. Global turning points in the phylogenetic and ecological diversification occurred after the end-Permian mass extinction and in the late Cretaceous. Fluctuations in amphibian diversification show strong temporal correlation with turnover rates in amniotes and the rise of angiosperm-dominated forests. Approximately 86% of modern frog species and >81% of salamander species descended from only five ancestral lineages that produced major radiations in the late Cretaceous and early Tertiary. This proportionally late accumulation of extant lineage diversity contrasts with the long evolutionary history of amphibians but is in line with the Tertiary increase in fossil abundance toward the present.
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Affiliation(s)
- Kim Roelants
- *Unit of Ecology and Systematics, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - David J. Gower
- Department of Zoology, Natural History Museum, London SW7 5BD, United Kingdom; and
| | - Mark Wilkinson
- Department of Zoology, Natural History Museum, London SW7 5BD, United Kingdom; and
| | - Simon P. Loader
- Department of Zoology, Natural History Museum, London SW7 5BD, United Kingdom; and
| | - S. D. Biju
- *Unit of Ecology and Systematics, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
- Centre for Environmental Management of Degraded Ecosystems, School of Environmental Studies, University of Delhi, Delhi 110007, India
| | - Karen Guillaume
- *Unit of Ecology and Systematics, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Linde Moriau
- *Unit of Ecology and Systematics, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Franky Bossuyt
- *Unit of Ecology and Systematics, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
- To whom correspondence should be addressed. E-mail:
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Axisa F, Brosteaux D, De Leersnyder E, Bossuyt F, Gonzalez M, De Smet N, Schacht E, Rymarczyk-Machal M, Vanfleteren J. Low cost, biocompatible elastic and conformable electronic technologies using MID in stretchable polymer. Annu Int Conf IEEE Eng Med Biol Soc 2007; 2007:6593-6596. [PMID: 18003536 DOI: 10.1109/iembs.2007.4353870] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
For user comfort reasons, electronic circuits for implantation in the human body or for use as smart clothes should ideally be soft, stretchable and elastic. In this contribution the results of an MID (Molded Interconnect Device) technology will be presented, showing the feasibility of functional stretchable electronic circuits. In the developed technology rigid or flexible standard components are interconnected by meander shaped metallic wires and embedded by molding in a stretchable substrate polymer. Several technologies have been developed to this purpose, which combine low cost and good reliability under mechanical strain. In this way reliable stretchability of the circuits above 100% has been demonstrated. Enhanced reliability has been reached using an additional conductive polymer layer.
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Affiliation(s)
- F Axisa
- IMEC/TFCG Microsystems, Ghent, Belgium.
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Abstract
Overseas dispersals are often invoked when Southern Hemisphere terrestrial and freshwater organism phylogenies do not fit the sequence or timing of Gondwana fragmentation. We used dispersal-vicariance analyses and molecular timetrees to show that two species-rich frog groups, Microhylidae and Natatanura, display congruent patterns of spatial and temporal diversification among Gondwanan plates in the Late Cretaceous, long after the presumed major tectonic break-up events. Because amphibians are notoriously salt-intolerant, these analogies are best explained by simultaneous vicariance, rather than by oceanic dispersal. Hence our results imply Late Cretaceous connections between most adjacent Gondwanan landmasses, an essential concept for biogeographic and palaeomap reconstructions.
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Affiliation(s)
- Ines Van Bocxlaer
- Biology Department, Unit of Ecology and Systematics, Vrije Universiteit BrusselBrussels, Belgium
| | - Kim Roelants
- Biology Department, Unit of Ecology and Systematics, Vrije Universiteit BrusselBrussels, Belgium
| | - S.D. Biju
- Biology Department, Unit of Ecology and Systematics, Vrije Universiteit BrusselBrussels, Belgium
- Centre for Environmental Management of Degraded Ecosystems (CEMDE), School of Environmental Studies, University of DelhiDelhi, India
| | - J. Nagaraju
- Laboratory of Molecular Genetics, Centre for DNA Fingerprinting and DiagnosticsHyderabad, India
| | - Franky Bossuyt
- Biology Department, Unit of Ecology and Systematics, Vrije Universiteit BrusselBrussels, Belgium
- * To whom correspondence should be addressed. E-mail:
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Bossuyt F, Brown RM, Hillis DM, Cannatella DC, Milinkovitch MC. Phylogeny and Biogeography of a Cosmopolitan Frog Radiation: Late Cretaceous Diversification Resulted in Continent-Scale Endemism in the Family Ranidae. Syst Biol 2006; 55:579-94. [PMID: 16857652 DOI: 10.1080/10635150600812551] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
Ranidae is a large anuran group with a nearly cosmopolitan distribution. We investigated the phylogenetic relationships and early biogeographic history of ranid frogs, using 104 representatives of all subfamilies and families, sampled from throughout their distribution. Analyses of approximately 1570 bp of nuclear gene fragments (Rag-1, rhod, Tyr) and approximately 2100 bp of the mitochondrial genome (12S rRNA, tRNAVAL, 16S rRNA) indicate that the monophyly of several taxa can be rejected with high confidence. Our tree is characterized by a clear historical association of each major clade with one Gondwanan plate. This prevalence of continent-scale endemism suggests that plate tectonics has played a major role in the distribution of ranid frogs. We performed dispersal-vicariance analyses, as well as analyses constrained by paleogeographic data, to estimate ancestral distributions during early ranid diversification. Additionally, we used molecular clock analyses to evaluate whether these scenarios fit the temporal framework of continental breakup. Our analyses suggest that a scenario in which the ancestors of several clades (Rhacophorinae, Dicroglossinae, Raninae) reached Eurasia via the Indian subcontinent, and the ancestor of Ceratobatrachinae entered via the Australia-New Guinea plate, best fits the paleogeographic models and requires the fewest number of dispersal/vicariance events. However, several alternatives, in which part of the ranid fauna colonized Laurasia from Africa, are not significantly worse. Most importantly, all hypotheses make clear predictions as to where to expect key fossils and where to sample other living ranids, and thus constitute a strong basis for further research.
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Affiliation(s)
- Franky Bossuyt
- Biology Department, Unit of Ecology & Systematics, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium.
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Mannaert A, Roelants K, Bossuyt F, Leyns L. A PCR survey for posterior Hox genes in amphibians. Mol Phylogenet Evol 2006; 38:449-58. [PMID: 16198128 DOI: 10.1016/j.ympev.2005.08.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2005] [Revised: 08/22/2005] [Accepted: 08/23/2005] [Indexed: 10/25/2022]
Abstract
Hox genes encode transcription factors that play a key role in specifying the body plan in metazoans and are therefore essential in explaining patterns of evolutionary diversity. As an ancient tetrapod group with diverse limb types, amphibians are important for understanding the origin and diversification of limbs in land vertebrates. We conducted a PCR survey in two species of each amphibian order to identify Hox-9 to Hox-13, known to function in limb development. Fifteen distinct posterior Hox genes and one retro-pseudogene were identified, and the former confirm the existence of four Hox clusters in each amphibian order. Some genes expected to occur in all tetrapods, based on the posterior Hox complement of mammals, fishes and coelacanth, were not recovered from our survey, and may have been lost. Hoxd-12 is absent in frogs and possibly other amphibians. Considering its function in autopodial development, the loss of this gene may be related to the absence of the fifth finger in frogs and salamanders.
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Affiliation(s)
- An Mannaert
- Department of Biology, Unit of Ecology and Systematics, Vrije Universiteit Brussel, VUB, Pleinlaan 2, 1050 Brussels, Belgium
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Abstract
AbstractThe oriental shrubfrog genus Philautus (Anura, Ranidae, Rhacophorinae) is a large group of direct-developing frogs that still holds several undescribed species on the Indian subcontinent. Here we describe two new species, Philautus anili sp. nov. and Philautus dubois sp. nov. from Wayanad (Kerala) and Kodaikanal (Tamil Nadu), respectively. Both species were collected from the township, where they are abundant in roadside vegetation and gardens, illustrating that several of the most common Western Ghats frogs are still not scientifically described. The two species are clearly distinct from all known species, but are morphologically similar to each other. However, Philautus anili differs from P. dubois by its larger snout-to-vent length, the sharp canthus rostralis, and the tibia that is longer than the femur.
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Abstract
Current models for the early diversification of living frogs inferred from morphological, ontogenetic, or DNA sequence data invoke very different scenarios of character evolution and biogeography. To explore central controversies on the phylogeny of Anura, we analyzed nearly 4000 base pairs of mitochondrial and nuclear DNA for the major frog lineages. Likelihood-based analyses of this data set are congruent with morphological evidence in supporting a paraphyletic arrangement of archaeobatrachian frogs, with an (Ascaphus + Leiopelma) clade as the sister-group of all other living anurans. The stability of this outcome is reinforced by screening for phylogenetic bias resulting from site-specific rate variation, homoplasy, or the obligatory use of distantly related outgroups. Twenty-one alternative branching and rooting hypotheses were evaluated using a nonparametric multicomparison test and parametric bootstrapping. Relaxed molecular clock estimates situate the emergence of crown-group anurans in the Triassic, approximately 55 million years prior to their first appearance in the fossil record. The existence of at least four extant frog lineages on the supercontinent Pangaea before its breakup gains support from the estimation that three early splits between Laurasia- and Gondwana-associated families coincide with the initial rifting of these landmasses. This observation outlines the potential significance of this breakup event in the formation of separate Mesozoic faunal assemblages in both hemispheres.
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Affiliation(s)
- Kim Roelants
- Biology Department, Unit of Ecology and Systematics, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
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Bossuyt F, Meegaskumbura M, Beenaerts N, Gower DJ, Pethiyagoda R, Roelants K, Mannaert A, Wilkinson M, Bahir MM, Manamendra-Arachchi K, Ng PKL, Schneider CJ, Oommen OV, Milinkovitch MC. Local endemism within the Western Ghats-sri Lanka biodiversity hotspot. Science 2004; 306:479-81. [PMID: 15486298 DOI: 10.1126/science.1100167] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The apparent biotic affinities between the mainland and the island in the Western Ghats-Sri Lanka biodiversity hotspot have been interpreted as the result of frequent migrations during recent periods of low sea level. We show, using molecular phylogenies of two invertebrate and four vertebrate groups, that biotic interchange between these areas has been much more limited than hitherto assumed. Despite several extended periods of land connection during the past 500,000 years, Sri Lanka has maintained a fauna that is largely distinct from that of the Indian mainland. Future conservation programs for the subcontinent should take into account such patterns of local endemism at the finest scale at which they may occur.
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Affiliation(s)
- Franky Bossuyt
- Biology Department, Unit of Ecology and Systematics, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium.
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Roelants K, Jiang J, Bossuyt F. Endemic ranid (Amphibia: Anura) genera in southern mountain ranges of the Indian subcontinent represent ancient frog lineages: evidence from molecular data. Mol Phylogenet Evol 2004; 31:730-40. [PMID: 15062806 DOI: 10.1016/j.ympev.2003.09.011] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2003] [Revised: 09/12/2003] [Indexed: 11/16/2022]
Abstract
The geological history of the Indian subcontinent is marked by successive episodes of extensive isolation, which have provided ideal settings for the development of a unique floral and faunal diversity. By molecular phylogenetic analysis of a large set of ranid frog taxa from the Oriental realm, we show that four genera, now restricted to torrential habitats in the Western Ghats of India and the central highlands of Sri Lanka, represent remnants of ancient divergences. None of three other biodiversity hotspots in the Oriental mainland were found to harbour an equivalent level of long-term evolutionary history in this frog group. By unceasingly providing favourable humid conditions, the subcontinent's southern mountain ranges have served as refugia for old lineages, and hence constitute a unique reservoir of ancient ranid endemism.
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Affiliation(s)
- Kim Roelants
- Department of Biology, Unit of Ecology and Systematics, Vrije Universiteit Brussel (Free University of Brussels), Pleinlaan 2, B-1050 Brussels, Belgium
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Biju SD, Bossuyt F. New frog family from India reveals an ancient biogeographical link with the Seychelles. Nature 2003; 425:711-4. [PMID: 14562102 DOI: 10.1038/nature02019] [Citation(s) in RCA: 185] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2003] [Accepted: 09/01/2003] [Indexed: 11/09/2022]
Abstract
About 96% of the more than 4,800 living anuran species belong to the Neobatrachia or advanced frogs. Because of the extremely poor representation of these animals in the Mesozoic fossil record, hypotheses on their early evolution have to rely largely on extant taxa. Here we report the discovery of a burrowing frog from India that is noticeably distinct from known taxa in all anuran families. Phylogenetic analyses of 2.8 kilobases of mitochondrial and nuclear DNA unambiguously designate this frog as the sister taxon of Sooglossidae, a family exclusively occurring on two granitic islands of the Seychelles archipelago. Furthermore, molecular clock analyses uncover the branch leading to both taxa as an ancient split in the crown-group Neobatrachia. Our discovery discloses a lineage that may have been more diverse on Indo-Madagascar in the Cretaceous period, but now only comprises four species on the Seychelles and a sole survivor in India. Because of its very distinct morphology and an inferred origin that is earlier than several neobatrachian families, we recognize this frog as a new family.
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Affiliation(s)
- S D Biju
- Tropical Botanic Garden and Research Institute, Palode, Thiruvananthapuram, 695562 Kerala, India
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Affiliation(s)
- M Meegaskumbura
- Biology Department, Boston University, Boston, MA 02215, USA
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Abstract
Sixty-five million years ago, massive volcanism produced on the India-Seychelles landmass the largest continental lava deposit (Deccan Traps) of the past 200 million years. Using a molecular clock-independent approach for inferring dating information from molecular phylogenies, we show that multiple lineages of frogs survived Deccan Traps volcanism after millions of years of isolation on drifting India. The collision between the Indian and Eurasian plates was followed by wide dispersal of several of these lineages. This "out-of-India" scenario reveals a zoogeographical pattern that might reconcile paleontological and molecular data in other vertebrate groups.
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Affiliation(s)
- F Bossuyt
- Unit of Evolutionary Genetics, Free University of Brussels (ULB), cp 300, Institute of Molecular Biology and Medicine, rue Jeener and Brachet 12, B-6041 Gosselies, Belgium
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Bossuyt F, Milinkovitch MC. Convergent adaptive radiations in Madagascan and Asian ranid frogs reveal covariation between larval and adult traits. Proc Natl Acad Sci U S A 2000; 97:6585-90. [PMID: 10841558 PMCID: PMC18667 DOI: 10.1073/pnas.97.12.6585] [Citation(s) in RCA: 240] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Recent studies have reported that independent adaptive radiations can lead to identical ecomorphs. Our phylogenetic analyses of nuclear and mitochondrial DNA sequences here indicate that a major radiation of ranid frogs on Madagascar produced morphological, physiological, and developmental characters that are remarkably similar to those that independently evolved on the Indian subcontinent. We demonstrate further that, in several cases, adult and larval stages each evolved sets of characters which are not only convergent between independent lineages, but also allowed both developmental stages to invade the same adaptive zone. It is likely that such covariations are produced by similar selective pressures on independent larval and adult characters rather than by genetic or functional linkage. We briefly discuss why larval/adult covariations might constitute an important evolutionary phenomenon in species for which more than one developmental stage potentially has access to multiple environmental conditions.
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Affiliation(s)
- F Bossuyt
- Unit of Evolutionary Genetics, Free University of Brussels (ULB), cp 300, Institute of Molecular Biology and Medicine, rue Jeener and Brachet 12, B-6041 Gosselies, Belgium
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