1
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Graham ZA, Padilla Perez DJ. Correlated evolution of conspicuous colouration and burrowing in crayfish. Proc Biol Sci 2024; 291:20240632. [PMID: 38981529 DOI: 10.1098/rspb.2024.0632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Accepted: 06/14/2024] [Indexed: 07/11/2024] Open
Abstract
Conspicuous colours have fascinated biologists for centuries, leading to research on the evolution and functional significance of colour traits. In many cases, research suggests that conspicuous colours are adaptive and serve a function in sexual or aposematic signalling. In other cases, a lack of evidence for the adaptive value of conspicuous colours garners interest from biologists, such as when organisms that live underground and are rarely exposed to the surface are nevertheless colourful. Here, we use phylogenetic comparative methods to investigate colour evolution throughout freshwater crayfishes that vary in burrowing ability. Within the taxa we analysed, conspicuous colours have evolved independently over 50 times, and these colours are more common in semi-terrestrial crayfishes that construct extensive burrows. The intuitive but not evolutionarily justified assumption when presented with these results is to assume that these colours are adaptive. But contrary to this intuition, we discuss the hypothesis that colouration in crayfish is neutral. Supporting these ideas, the small population sizes and reduced gene flow within semi-terrestrial burrowing crayfishes may lead to the fixation of colour-phenotype mutations. Overall, our work brings into question the traditional view of animal colouration as a perfectly adapted phenotype.
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Affiliation(s)
- Zackary A Graham
- Department of Organismal Biology, Ecology, and Zoo Science, West Liberty University, 208 University Drive , West Liberty, WV 26074, USA
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2
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Kouete MT, Bletz MC, LaBumbard BC, Woodhams DC, Blackburn DC. Parental care contributes to vertical transmission of microbes in a skin-feeding and direct-developing caecilian. Anim Microbiome 2023; 5:28. [PMID: 37189209 PMCID: PMC10184399 DOI: 10.1186/s42523-023-00243-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Accepted: 03/20/2023] [Indexed: 05/17/2023] Open
Abstract
BACKGROUND Our current understanding of vertebrate skin and gut microbiomes, and their vertical transmission, remains incomplete as major lineages and varied forms of parental care remain unexplored. The diverse and elaborate forms of parental care exhibited by amphibians constitute an ideal system to study microbe transmission, yet investigations of vertical transmission among frogs and salamanders have been inconclusive. In this study, we assess bacteria transmission in Herpele squalostoma, an oviparous direct-developing caecilian in which females obligately attend juveniles that feed on their mother's skin (dermatophagy). RESULTS We used 16S rRNA amplicon-sequencing of the skin and gut of wild caught H. squalostoma individuals (males, females, including those attending juveniles) as well as environmental samples. Sourcetracker analyses revealed that juveniles obtain an important portion of their skin and gut bacteria communities from their mother. The contribution of a mother's skin to the skin and gut of her respective juveniles was much larger than that of any other bacteria source. In contrast to males and females not attending juveniles, only the skins of juveniles and their mothers were colonized by bacteria taxa Verrucomicrobiaceae, Nocardioidaceae, and Erysipelotrichaceae. In addition to providing indirect evidence for microbiome transmission linked to parental care among amphibians, our study also points to noticeable differences between the skin and gut communities of H. squalostoma and that of many frogs and salamanders, which warrants further investigation. CONCLUSION Our study is the first to find strong support for vertical bacteria transmission attributed to parental care in a direct-developing amphibian species. This suggests that obligate parental care may promote microbiome transmission in caecilians.
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Affiliation(s)
- Marcel T Kouete
- School of Natural Resources and Environment, University of Florida, Gainesville, FL, 32611, USA.
- Department of Natural History, Florida Museum of Natural History, University of Florida, Gainesville, FL, 32611, USA.
| | - Molly C Bletz
- Department of Biology, University of Massachusetts, Boston, MA, 02125, USA
| | | | - Douglas C Woodhams
- Department of Biology, University of Massachusetts, Boston, MA, 02125, USA
| | - David C Blackburn
- Department of Natural History, Florida Museum of Natural History, University of Florida, Gainesville, FL, 32611, USA
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3
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Loeffler-Henry K, Kang C, Sherratt TN. Evolutionary transitions from camouflage to aposematism: Hidden signals play a pivotal role. Science 2023; 379:1136-1140. [PMID: 36927015 DOI: 10.1126/science.ade5156] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
Abstract
The initial evolution of warning signals in unprofitable prey, termed aposematism, is often seen as a paradox because any new conspicuous mutant would be easier to detect than its cryptic conspecifics and not readily recognized by naïve predators as defended. One possibility is that permanent aposematism first evolved through species using hidden warning signals, which are only exposed to would-be predators on encounter. Here, we present a large-scale analysis of evolutionary transitions in amphibian antipredation coloration and demonstrate that the evolutionary transition from camouflage to aposematism is rarely direct but tends to involve an intermediary stage, namely cryptic species that facultatively reveal conspicuous coloration. Accounting for this intermediate step can resolve the paradox and thereby advance our understanding of the evolution of aposematism.
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Affiliation(s)
| | - Changku Kang
- Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, South Korea
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, South Korea
| | - Thomas N Sherratt
- Department of Biology, Carleton University, Ottawa, Ontario K1S 5B6, Canada
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4
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Lowie A, De Kegel B, Wilkinson M, Measey J, O'Reilly JC, Kley NJ, Gaucher P, Adriaens D, Herrel A. The anatomy of the head muscles in caecilians (Amphibia: Gymnophiona): Variation in relation to phylogeny and ecology? J Anat 2023; 242:312-326. [PMID: 36087281 PMCID: PMC9877473 DOI: 10.1111/joa.13763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 08/07/2022] [Accepted: 08/29/2022] [Indexed: 02/01/2023] Open
Abstract
In limbless fossorial vertebrates such as caecilians (Gymnophiona), head-first burrowing imposes severe constraints on the morphology and overall size of the head. As such, caecilians developed a unique jaw-closing system involving the large and well-developed m. interhyoideus posterior, which is positioned in such a way that it does not significantly increase head diameter. Caecilians also possess unique muscles among amphibians. Understanding the diversity in the architecture and size of the cranial muscles may provide insights into how a typical amphibian system was adapted for a head-first burrowing lifestyle. In this study, we use dissection and non-destructive contrast-enhanced micro-computed tomography (μCT) scanning to describe and compare the cranial musculature of 13 species of caecilians. Our results show that the general organization of the head musculature is rather constant across extant caecilians. However, the early-diverging Rhinatrema bivittatum mainly relies on the 'ancestral' amphibian jaw-closing mechanism dominated by the m. adductores mandibulae, whereas other caecilians switched to the use of the derived dual jaw-closing mechanism involving the additional recruitment of the m. interhyoideus posterior. Additionally, the aquatic Typhlonectes show a greater investment in hyoid musculature than terrestrial caecilians, which is likely related to greater demands for ventilating their large lungs, and perhaps also an increased use of suction feeding. In addition to three-dimensional interactive models, our study provides the required quantitative data to permit the generation of accurate biomechanical models allowing the testing of further functional hypotheses.
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Affiliation(s)
- Aurélien Lowie
- Ghent University, Department of Biology, Evolutionary Morphology of Vertebrates, Ghent, Belgium
| | - Barbara De Kegel
- Ghent University, Department of Biology, Evolutionary Morphology of Vertebrates, Ghent, Belgium
| | - Mark Wilkinson
- Department of Life Sciences, Natural History Museum, London, UK
| | - John Measey
- Centre for Invasion Biology, Department of Botany & Zoology, Stellenbosch University, Stellenbosch, South Africa
| | - James C O'Reilly
- Department of Biomedical Sciences, Ohio University, Cleveland Campus, Cleveland, Ohio, USA
| | - Nathan J Kley
- Department of Anatomical Sciences, Health Sciences Center, Stony Brook University, Stony Brook, New York, USA
| | - Philippe Gaucher
- USR 3456, CNRS, Centre de recherche de Montabo IRD, Cayenne, France
| | - Dominique Adriaens
- Ghent University, Department of Biology, Evolutionary Morphology of Vertebrates, Ghent, Belgium
| | - Anthony Herrel
- Ghent University, Department of Biology, Evolutionary Morphology of Vertebrates, Ghent, Belgium.,UMR 7179 C.N.R.S/M.N.H.N., Département d'Ecologie et de Gestion de la Biodiversité, Paris Cedex 5, France
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5
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Robinson ML, Weber MG, Freedman MG, Jordan E, Ashlock SR, Yonenaga J, Strauss SY. Macroevolution of protective coloration across caterpillars reflects relationships with host plants. Proc Biol Sci 2023; 290:20222293. [PMID: 36651051 PMCID: PMC9845978 DOI: 10.1098/rspb.2022.2293] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
A critical function of animal coloration is avoiding attack, either by warning predators or reducing detectability. Evolution of these divergent strategies may depend on prey palatability and apparency to predators: conspicuous coloration may be favoured if species are distasteful, or habitats make hiding difficult; by contrast, camouflage may be effective if prey lack defences or environments are visually complex. For insect herbivores, host plants provide both chemical defence and the background against which they are detected or obscured; thus, plant traits may be key to coloration in these foundational terrestrial organisms. We use 1808 species of larval Lepidoptera to explore macroevolution of protective coloration strategy. We find that colour and pattern evolve jointly in caterpillars, similar to an array of species across the animal kingdom, while individual elements of coloration evolve closely with diet ecology. Consistent with key tenets of plant defence and plant-herbivore coevolutionary theory, conspicuous colours are associated with herbaceous host plants-thought to be defended by toxins-while camouflage colours and patterns are associated with woody plants and grasses. Contrary to theory, dietary specialization is not associated with conspicuous coloration. Our results add valuable insights into the evolutionary forces shaping colour and pattern in nature.
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Affiliation(s)
- Moria L. Robinson
- Center for Population Biology, University of California, Davis, CA 95616, USA,Department of Biology, Utah State University, Logan, Utah 84322, USA
| | - Marjorie G. Weber
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Micah G. Freedman
- Center for Population Biology, University of California, Davis, CA 95616, USA,Department of Ecology and Evolution, University of Chicago, Chicago, IL 60637, USA
| | - Evan Jordan
- Department of Evolution and Ecology, University of California, CA 95616, USA
| | - Sarah R. Ashlock
- Department of Evolution and Ecology, University of California, CA 95616, USA
| | - Jenna Yonenaga
- Department of Evolution and Ecology, University of California, CA 95616, USA
| | - Sharon Y. Strauss
- Center for Population Biology, University of California, Davis, CA 95616, USA,Wissenschaftskolleg zu Berlin, Berlin, 14193, Germany,Department of Evolution and Ecology, University of California, CA 95616, USA
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6
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Hyeun-Ji L, Rendón MÁ, Liedtke HC, Gomez-Mestre I. Shifts in the developmental rate of spadefoot toad larvae cause decreased complexity of post-metamorphic pigmentation patterns. Sci Rep 2020; 10:19624. [PMID: 33184389 PMCID: PMC7665075 DOI: 10.1038/s41598-020-76578-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 10/27/2020] [Indexed: 11/18/2022] Open
Abstract
Amphibian larvae are plastic organisms that can adjust their growth and developmental rates to local environmental conditions. The consequences of such developmental alterations have been studied in detail, both at the phenotypic and physiological levels. While largely unknown, it is of great importance to assess how developmental alterations affect the pigmentation pattern of the resulting metamorphs, because pigmentation is relevant for communication, mate choice, and camouflage and hence influences the overall fitness of the toads. Here we quantify the variation in several aspects of the pigmentation pattern of juvenile spadefoot toads experimentally induced to accelerate their larval development in response to decreased water level. It is known that induced developmental acceleration comes at the cost of reduced size at metamorphosis, higher metabolic rate, and increased oxidative stress. In this study, we show that spadefoot toads undergoing developmental acceleration metamorphosed with a less complex, more homogeneous, darker dorsal pattern consisting of continuous blotches, compared to the more contrasted pattern with segregated blotches and higher fractal dimension in normally developing individuals, and at a smaller size. We also observed a marked effect of population of origin in the complexity of the pigmentation pattern. Complexity of the post-metamorphic dorsal pigmentation could therefore be linked to pre-metamorphic larval growth and development.
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Affiliation(s)
- Lee Hyeun-Ji
- Ecology, Evolution, and Development Group, Doñana Biological Station, Consejo Superior de Investigaciones Científicas, 41092, Seville, Spain
- Department of Wetland Ecology, Doñana Biological Station, Consejo Superior de Investigaciones Científicas, 41092, Seville, Spain
| | - Miguel Ángel Rendón
- Department of Wetland Ecology, Doñana Biological Station, Consejo Superior de Investigaciones Científicas, 41092, Seville, Spain
| | - Hans Christoph Liedtke
- Ecology, Evolution, and Development Group, Doñana Biological Station, Consejo Superior de Investigaciones Científicas, 41092, Seville, Spain
- Department of Wetland Ecology, Doñana Biological Station, Consejo Superior de Investigaciones Científicas, 41092, Seville, Spain
| | - Ivan Gomez-Mestre
- Ecology, Evolution, and Development Group, Doñana Biological Station, Consejo Superior de Investigaciones Científicas, 41092, Seville, Spain.
- Department of Wetland Ecology, Doñana Biological Station, Consejo Superior de Investigaciones Científicas, 41092, Seville, Spain.
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7
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Cyriac VP, Kodandaramaiah U. Warning signals promote morphological diversification in fossorial uropeltid snakes (Squamata: Uropeltidae). Zool J Linn Soc 2020. [DOI: 10.1093/zoolinnean/zlaa062] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract
Many species possess warning colourations that signal unprofitability to predators. Warning colourations are also thought to provide prey with a ‘predator-free space’ and promote niche expansion. However, how such strategies release a species from environmental constraints and facilitate niche expansion is not clearly understood. Fossoriality in reptiles imposes several morphological limits on head and body size to facilitate burrowing underground, but many fossorial snakes live close to the surface and occasionally move above ground, exposing them to predators. In such cases, evolving antipredator defences that reduce predation on the surface could potentially relax the morphological constraints associated with fossoriality and promote morphological diversification. Fossorial uropeltid snakes possess varying degrees of conspicuous warning colourations that reduce avian predation when active above ground. We predicted that species with more conspicuous colourations will exhibit more robust body forms and show faster rates of morphological evolution because constraints imposed by fossoriality are relaxed. Using a comparative phylogenetic approach on the genus Uropeltis, we show that more conspicuous species tend to have more robust morphologies and have faster rates of head-shape evolution. Overall, we find that the evolution of warning colourations in Uropeltis can facilitate niche expansion by influencing rates of morphological diversification.
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Affiliation(s)
- Vivek Philip Cyriac
- IISER-TVM Centre for Research and Education in Ecology and Evolution (ICREEE) and School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, Maruthamala P.O., Vithura, Thiruvananthapuram, India
| | - Ullasa Kodandaramaiah
- IISER-TVM Centre for Research and Education in Ecology and Evolution (ICREEE) and School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, Maruthamala P.O., Vithura, Thiruvananthapuram, India
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8
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Allen WL, Moreno N, Gamble T, Chiari Y. Ecological, behavioral, and phylogenetic influences on the evolution of dorsal color pattern in geckos. Evolution 2020; 74:1033-1047. [PMID: 31886521 DOI: 10.1111/evo.13915] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 12/04/2019] [Accepted: 12/15/2019] [Indexed: 12/13/2022]
Abstract
The dorsal surfaces of many taxonomic groups often feature repetitive pattern elements consisting of stripes, spots, or bands. Here, we investigate how distinct categories of camouflage pattern work by relating them to ecological and behavioral traits in 439 species of gecko. We use phylogenetic comparative methods to test outstanding hypotheses based on camouflage theory and research in other taxa. We found that bands are associated with nocturnal activity, suggesting bands provide effective camouflage for motionless geckos resting in refugia during the day. A predicted association between stripes and diurnal activity was not supported, suggesting that stripes do not work via dazzle camouflage mechanisms in geckos. This, along with a lack of support for our prediction that plain patterning should be associated with open habitats, suggests that similar camouflage patterns do not work in consistent ways across taxa. We also found that plain and striped lineages frequently switched between using open or closed habitats, whereas spotted lineages rarely transitioned. This suggests that pattern categories differ in how specialized or generalized their camouflage is. This result has ramifications for theory on how camouflage compromises to background heterogeneity and how camouflage pattern might influence evolutionary trajectories.
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Affiliation(s)
- William L Allen
- Department of Biosciences, Swansea University, Swansea, UK, SA2 8PP
| | - Nickolas Moreno
- Department of Biology, University of South Alabama, Mobile, Alabama, 36688
| | - Tony Gamble
- Department of Biological Sciences, Marquette University, Milwaukee, Wisconsin, 53233.,Bell Museum of Natural History, University of Minnesota, Saint Paul, Minnesota, 55113.,Milwaukee Public Museum, Milwaukee, Wisconsin, 53233
| | - Ylenia Chiari
- Department of Biology, University of South Alabama, Mobile, Alabama, 36688.,Department of Biology, George Mason University, Manassas, Virginia, 20110
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9
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Kouete MT, Blackburn DC. Dietary Partitioning in Two Co-occurring Caecilian Species ( Geotrypetes seraphini and Herpele squalostoma) in Central Africa. Integr Org Biol 2019; 2:obz035. [PMID: 33791585 PMCID: PMC7671121 DOI: 10.1093/iob/obz035] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Trophic interactions among fossorial vertebrates remain poorly explored in tropical ecosystems. While caecilian species can co-occur, whether and how sympatric species partition dietary or other resources are largely unknown. Based on specimens collected during field surveys in southern Cameroon, we conducted a dietary analysis of two co-occurring caecilian species, Geotrypetes seraphini and Herpele squalostoma. We find a negligible overlap in the adult diets of these two species. Earthworms dominated the diet of adult G. seraphini, whereas we found that mole crickets were the most frequent prey items in adult H. squalostoma. The dietary breadth of adult G. seraphini is smaller than that of H. squalostoma, which consumes a variety of hard-bodied prey including mole crickets, cockroaches, beetles, and crabs. Juvenile diets were similar between these species and mostly contained earthworms and ants. We did not detect significant ontogenetic dietary shifts in either species, though adults generally consumed a broader diversity of prey. As adults, G. seraphini and H. squalostoma may partition prey categories by consuming soft-bodied and hard-bodied prey, respectively. Because most caecilians are likely opportunistic predators, we expect that sympatric species partition dietary resources either by preference for different soil layers or ability to consume different prey categories.
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Affiliation(s)
- M T Kouete
- California Academy of Sciences, San Francisco, CA 94118, USA.,Department of Natural History, Florida Museum of Natural History, University of Florida, Gainesville, FL 32611, USA
| | - D C Blackburn
- Department of Natural History, Florida Museum of Natural History, University of Florida, Gainesville, FL 32611, USA
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10
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Dallagnol Vargas N, Guimarães M, Caorsi V, Wolff Bordignon D, Borges‐Martins M. An experimental assessment of the antipredatory function of green dorsal coloration in poisonous Neotropical red‐bellied toads. J Zool (1987) 2019. [DOI: 10.1111/jzo.12740] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Natália Dallagnol Vargas
- Programa de Pós‐graduação em Biologia Animal Departamento de Zoologia Instituto de Biociências Universidade Federal do Rio Grande do Sul Porto Alegre Rio Grande do Sul Brazil
| | - Murilo Guimarães
- Programa de Pós‐graduação em Biologia Animal Departamento de Zoologia Instituto de Biociências Universidade Federal do Rio Grande do Sul Porto Alegre Rio Grande do Sul Brazil
| | - Valentina Caorsi
- Programa de Pós‐graduação em Biologia Animal Departamento de Zoologia Instituto de Biociências Universidade Federal do Rio Grande do Sul Porto Alegre Rio Grande do Sul Brazil
- The Istituto Agrario di San Michele all’Adige Research and Innovation Centre Fondazione Edmund Mach San Michele all’Adige TN Italy
| | - Debora Wolff Bordignon
- Programa de Pós‐graduação em Biologia Animal Departamento de Zoologia Instituto de Biociências Universidade Federal do Rio Grande do Sul Porto Alegre Rio Grande do Sul Brazil
| | - Márcio Borges‐Martins
- Programa de Pós‐graduação em Biologia Animal Departamento de Zoologia Instituto de Biociências Universidade Federal do Rio Grande do Sul Porto Alegre Rio Grande do Sul Brazil
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11
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Cyriac VP, Kodandaramaiah U. Conspicuous colours reduce predation rates in fossorial uropeltid snakes. PeerJ 2019; 7:e7508. [PMID: 31428543 PMCID: PMC6698130 DOI: 10.7717/peerj.7508] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 07/17/2019] [Indexed: 01/04/2023] Open
Abstract
Uropeltid snakes (Family Uropeltidae) are non-venomous, fossorial snakes that are found above ground occasionally, during which time they are exposed to predation. Many species are brightly coloured, mostly on the ventral surface, but these colours are expected to have no function below the ground. Observations have shown that the cephalic resemblance (resemblance to heads) of uropeltid tails may direct attacks of predators towards the hardened tails, thereby potentially increasing handling times for predators. Experiments have also shown that predators learn to avoid prey that are non-toxic and palatable but are difficult to capture, hard to process or require long handling time when such prey advertise their unprofitability through conspicuous colours. We here postulate that uropeltid snakes use their bright colours to signal long handling times associated with attack deflection to the tails, thereby securing reduced predation from predators that can learn to associate colour with handling time. Captive chicken experiments with dough models mimicking uropeltids indicate that attacks were more common on the tail than on the head. Field experiments with uropeltid clay models show that the conspicuous colours of these snakes decrease predation rates compared to cryptic models, but a novel conspicuous colour did not confer such a benefit. Overall, our experiments provide support for our hypothesis that the conspicuous colours of these snakes reduce predation, possibly because these colours advertise unprofitability due to long handling times.
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Affiliation(s)
- Vivek Philip Cyriac
- IISER-TVM Centre for Research and Education in Ecology and Evolution and School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, Kerala, India
| | - Ullasa Kodandaramaiah
- IISER-TVM Centre for Research and Education in Ecology and Evolution and School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, Kerala, India
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12
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Frynta D, Peléšková Š, Rádlová S, Janovcová M, Landová E. Human evaluation of amphibian species: a comparison of disgust and beauty. Naturwissenschaften 2019; 106:41. [PMID: 31263997 DOI: 10.1007/s00114-019-1635-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 06/10/2019] [Accepted: 06/14/2019] [Indexed: 12/19/2022]
Abstract
Animals can evoke a wide range of emotions helping us to choose a quick and appropriate reaction towards them: approach or avoidance in general. This work has focused on disgust evoked by amphibians in humans as well as perceived beauty. Due to the high morphological variability of recent amphibian taxa, we examined humans' cognitive categorisation of 101 amphibian photos and the effect of stimuli characteristics on disgust evaluation or beauty perception of individual groups/species. We also explored how respondents' characteristics, e.g. gender, age and disgust sensitivity (DS-R) influence the disgust and beauty evaluation of picture stimuli on a 7-point Likert scale. The scores of disgust and beauty evaluation were strongly negatively correlated, representing the opposite ends of a single axis, further referred to as the index of preference. The most preferred amphibians belonged to anurans, whereas the least preferred ones were mostly worm-like, legless and small-eyed caecilians. Additional analyses of morphologically diverse anurans showed that species with a round body shape, short forelegs, small eyes, warts, pink and grey colouration, or dark and dull colouration were perceived as disgusting or ugly. The effect of gender and age were only marginal; however, people with higher disgust sensitivity rated amphibians as more disgusting and less beautiful, which might support the hypothesis of a possible disgust involvement in animal fears and phobias. This topic has implications not only for the nature conservation decisions of globally endangered amphibians but also for understanding the evolution of disgust and its generalisation to harmless animals.
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Affiliation(s)
- Daniel Frynta
- Department of Zoology, Faculty of Science, Charles University in Prague, Viničná 7, 128 43, Prague, Czech Republic.,National Institute of Mental Health, Topolová 748, 250 67, Klecany, Czech Republic
| | - Šárka Peléšková
- Department of Zoology, Faculty of Science, Charles University in Prague, Viničná 7, 128 43, Prague, Czech Republic.,National Institute of Mental Health, Topolová 748, 250 67, Klecany, Czech Republic
| | - Silvie Rádlová
- National Institute of Mental Health, Topolová 748, 250 67, Klecany, Czech Republic
| | - Markéta Janovcová
- Department of Zoology, Faculty of Science, Charles University in Prague, Viničná 7, 128 43, Prague, Czech Republic.,National Institute of Mental Health, Topolová 748, 250 67, Klecany, Czech Republic
| | - Eva Landová
- Department of Zoology, Faculty of Science, Charles University in Prague, Viničná 7, 128 43, Prague, Czech Republic. .,National Institute of Mental Health, Topolová 748, 250 67, Klecany, Czech Republic.
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13
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Torres-Sánchez M, Gower DJ, Alvarez-Ponce D, Creevey CJ, Wilkinson M, San Mauro D. What lies beneath? Molecular evolution during the radiation of caecilian amphibians. BMC Genomics 2019; 20:354. [PMID: 31072350 PMCID: PMC6507065 DOI: 10.1186/s12864-019-5694-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 04/15/2019] [Indexed: 12/12/2022] Open
Abstract
Background Evolution leaves an imprint in species through genetic change. At the molecular level, evolutionary changes can be explored by studying ratios of nucleotide substitutions. The interplay among molecular evolution, derived phenotypes, and ecological ranges can provide insights into adaptive radiations. Caecilians (order Gymnophiona), probably the least known of the major lineages of vertebrates, are limbless tropical amphibians, with adults of most species burrowing in soils (fossoriality). This enigmatic order of amphibians are very distinct phenotypically from other extant amphibians and likely from the ancestor of Lissamphibia, but little to nothing is known about the molecular changes underpinning their radiation. We hypothesised that colonization of various depths of tropical soils and of freshwater habitats presented new ecological opportunities to caecilians. Results A total of 8540 candidate groups of orthologous genes from transcriptomic data of five species of caecilian amphibians and the genome of the frog Xenopus tropicalis were analysed in order to investigate the genetic machinery behind caecilian diversification. We found a total of 168 protein-coding genes with signatures of positive selection at different evolutionary times during the radiation of caecilians. The majority of these genes were related to functional elements of the cell membrane and extracellular matrix with expression in several different tissues. The first colonization of the tropical soils was connected to the largest number of protein-coding genes under positive selection in our analysis. From the results of our study, we highlighted molecular changes in genes involved in perception, reduction-oxidation processes, and aging that likely were involved in the adaptation to different soil strata. Conclusions The genes inferred to have been under positive selection provide valuable insights into caecilian evolution, potentially underpin adaptations of caecilians to their extreme environments, and contribute to a better understanding of fossorial adaptations and molecular evolution in vertebrates. Electronic supplementary material The online version of this article (10.1186/s12864-019-5694-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- María Torres-Sánchez
- Department of Biodiversity, Ecology and Evolution, Complutense University of Madrid, 28040, Madrid, Spain. .,Present address: Department of Neuroscience, Spinal Cord and Brain Injury Research Center & Ambystoma Genetic Stock Center, University of Kentucky, Lexington, KY, 40536, USA.
| | - David J Gower
- Department of Life Sciences, The Natural History Museum, London, SW7 5BD, UK
| | | | - Christopher J Creevey
- Institute for Global Food Security, Queen's University Belfast, University Road, Belfast, BT7 1NN, Northern Ireland, UK
| | - Mark Wilkinson
- Department of Life Sciences, The Natural History Museum, London, SW7 5BD, UK
| | - Diego San Mauro
- Department of Biodiversity, Ecology and Evolution, Complutense University of Madrid, 28040, Madrid, Spain
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Bertolesi GE, Zhang JZ, McFarlane S. Plasticity for colour adaptation in vertebrates explained by the evolution of the genes pomc, pmch and pmchl. Pigment Cell Melanoma Res 2019; 32:510-527. [PMID: 30791235 PMCID: PMC7167667 DOI: 10.1111/pcmr.12776] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Revised: 01/27/2019] [Accepted: 02/16/2019] [Indexed: 02/06/2023]
Abstract
Different camouflages work best with some background matching colour. Our understanding of the evolution of skin colour is based mainly on the genetics of pigmentation ("background matching"), with little known about the evolution of the neuroendocrine systems that facilitate "background adaptation" through colour phenotypic plasticity. To address the latter, we studied the evolution in vertebrates of three genes, pomc, pmch and pmchl, that code for α-MSH and two melanin-concentrating hormones (MCH and MCHL). These hormones induce either dispersion/aggregation or the synthesis of pigments. We find that α-MSH is highly conserved during evolution, as is its role in dispersing/synthesizing pigments. Also conserved is the three-exon pmch gene that encodes MCH, which participates in feeding behaviours. In contrast, pmchl (known previously as pmch), is a teleost-specific intron-less gene. Our data indicate that in zebrafish, pmchl-expressing neurons extend axons to the pituitary, supportive of an MCHL hormonal role, whereas zebrafish and Xenopus pmch+ neurons send axons dorsally in the brain. The evolution of these genes and acquisition of hormonal status for MCHL explain different mechanisms used by vertebrates to background-adapt.
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Affiliation(s)
- Gabriel E Bertolesi
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - John Zhijia Zhang
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Sarah McFarlane
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
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Winebarger MM, Pugh MW, Gangloff MM, Osbourn MS, Siefferman L. Body Size Is Positively Correlated With Conspicuous Coloration in Ambystoma Salamanders, but Negatively Correlated With Conspicuous Coloration in Plethodon Salamanders. Front Ecol Evol 2018. [DOI: 10.3389/fevo.2018.00143] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Beukema W, Nicieza AG, Lourenço A, Velo-Antón G. Colour polymorphism inSalamandra salamandra(Amphibia: Urodela), revealed by a lack of genetic and environmental differentiation between distinct phenotypes. J ZOOL SYST EVOL RES 2016. [DOI: 10.1111/jzs.12119] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Wouter Beukema
- CIBIO/InBIO; Centro de Investigação em Biodiversidade e Recursos Genéticos; Instituto de Ciências Agrárias de Vairão; Universidade do Porto; Vairão Portugal
- Department of Pathology; Bacteriology and Avian Diseases; Faculty of Veterinary Medicine; Ghent University; Merelbeke Belgium
| | - Alfredo G. Nicieza
- Departamento de Biología de Organismos y Sistemas; Universidad de Oviedo; Oviedo Spain
- Unidad Mixta de Investigación en Biodiversidad (UMIB); CSIC-Universidad de Oviedo-Principado de Asturias; Mieres Spain
| | - André Lourenço
- CIBIO/InBIO; Centro de Investigação em Biodiversidade e Recursos Genéticos; Instituto de Ciências Agrárias de Vairão; Universidade do Porto; Vairão Portugal
| | - Guillermo Velo-Antón
- CIBIO/InBIO; Centro de Investigação em Biodiversidade e Recursos Genéticos; Instituto de Ciências Agrárias de Vairão; Universidade do Porto; Vairão Portugal
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Stoelting RE, Measey GJ, Drewes RC. Population genetics of the São Tomé caecilian (Gymnophiona: Dermophiidae: Schistometopum thomense) reveals strong geographic structuring. PLoS One 2014; 9:e104628. [PMID: 25171066 PMCID: PMC4149351 DOI: 10.1371/journal.pone.0104628] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Accepted: 07/15/2014] [Indexed: 11/18/2022] Open
Abstract
Islands provide exciting opportunities for exploring ecological and evolutionary mechanisms. The oceanic island of São Tomé in the Gulf of Guinea exhibits high diversity of fauna including the endemic caecilian amphibian, Schistometopum thomense. Variation in pigmentation, morphology and size of this taxon over its c. 45 km island range is extreme, motivating a number of taxonomic, ecological, and evolutionary hypotheses to explain the observed diversity. We conducted a population genetic study of S. thomense using partial sequences of two mitochondrial DNA genes (ND4 and 16S), together with morphological examination, to address competing hypotheses of taxonomic or clinal variation. Using Bayesian phylogenetic analysis and Spatial Analysis of Molecular Variance, we found evidence of four geographic clades, whose range and approximated age (c. 253 Kya – 27 Kya) are consistent with the spread and age of recent volcanic flows. These clades explained 90% of variation in ND4 (φCT = 0.892), and diverged by 4.3% minimum pairwise distance at the deepest node. Most notably, using Mismatch Distributions and Mantel Tests, we identified a zone of population admixture that dissected the island. In the northern clade, we found evidence of recent population expansion (Fu's Fs = −13.08 and Tajima's D = −1.80) and limited dispersal (Mantel correlation coefficient = 0.36, p = 0.01). Color assignment to clades was not absolute. Paired with multinomial regression of chromatic data, our analyses suggested that the genetic groups and a latitudinal gradient together describe variation in color of S. thomense. We propose that volcanism and limited dispersal ability are the likely proximal causes of the observed genetic structure. This is the first population genetic study of any caecilian and demonstrates that these animals have deep genetic divisions over very small areas in accordance with previous speculations of low dispersal abilities.
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Affiliation(s)
- Ricka E. Stoelting
- Department of Herpetology, California Academy of Sciences, San Francisco, California, United States of America
- Department of Forest and Wildlife Ecology, University of Wisconsin, Madison, Wisconsin, United States of America
- * E-mail:
| | - G. John Measey
- Centre for Invasion Biology, Department of Botany and Zoology, University of Stellenbosch, Stellenbosch, South Africa
| | - Robert C. Drewes
- Department of Herpetology, California Academy of Sciences, San Francisco, California, United States of America
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Adaptive colouration in amphibians. Semin Cell Dev Biol 2013; 24:553-61. [DOI: 10.1016/j.semcdb.2013.05.004] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Revised: 04/12/2013] [Accepted: 05/01/2013] [Indexed: 11/20/2022]
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Measey GJ, Muchai V, Spawls S. Rediscovery of Boulengerula denhardtiNieden 1912 (Amphibia: Gymnophiona: Caeciliidae) in Meru County, Kenya. AFRICAN ZOOLOGY 2012. [DOI: 10.3377/004.047.0118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
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Ribeiro S, Nogueira C, Cintra CED, Da Silva NJ, Zaher H. Description of a New PoredLeposternon(Squamata, Amphisbaenidae) from the Brazilian Cerrado. SOUTH AMERICAN JOURNAL OF HERPETOLOGY 2011. [DOI: 10.2994/057.006.0303] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Measey GJ, Hinkel HH, Dumbo B, Fischer E. Rediscovery ofBoulengerula fischeri, with notes on its morphology and habitat. AFR J HERPETOL 2011. [DOI: 10.1080/21564574.2011.564659] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Herrel A, Measey GJ. The kinematics of locomotion in caecilians: effects of substrate and body shape. ACTA ACUST UNITED AC 2010; 313:301-9. [DOI: 10.1002/jez.599] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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