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Júlia Roberta Sá Pontes - One of the best experts on this subject based on the ideXlab platform.
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Descrição morfológica da ontogenia de Hippocampus reidi Ginsburg, 1933 (Teleostei, Syngnathidae): período embrionário à fase reprodutiva
Universidade Federal da Paraíba, 2010Co-Authors: Júlia Roberta Sá PontesAbstract:Estudos acerca da ontogenia constituem uma etapa importante para ampliar o entendimento sobre mudanças na preferência alimentar e por micro-habitats, bem como para o aprimoramento da taxonomia, otimização da produção em s e l e ; a r i e u q s e p o ã t s e g a a r a p e a r u t l u c i u q a a m u r a i c i p o r p m e d o p m é b m a t maior compreensão acerca das implicações da extração de um alto volume de animais para o comércio. O presente trabalho buscou estimar o crescimento inicial da espécie de cavalo-marinho Hippocampus reidi e descrever morfologicamente sua ontogenia, do período embrionário à fase reprodutiva. Ambos aspectos são relevantes face às (1) singularidades morfológicas e biológicas do gênero, que incluem a capacidade de dobrar o corpo dorsoventralmente e a presença de placas ósseas dispostas em forma de anel ao longo do corpo, a cauda preênsil e o desenvolvimento de uma bolsa incubadora nos machos e (2) à necessidade de ampliar o conhecimento acerca da biologia e ecologia dos cavalos-marinhos, um grupo globalmente ameaçado pela sobrepesca e pela perda de habitat. Para a análise de crescimento, foram obtidos dados ex-situ de duas diferentes proles de H. reidi. A descrição ontogenética foi realizada utilizando-se dados obtidos in-situ e ex-situ . Foram consideradas duas fases distintas: planctônica e pós-planctônica (quando os jovens são capazes de se prender a estruturas de apoio). Principais resultados obtidos no estudo: H. reidi apresentou uma taxa de crescimento inicial de 0,017 cm ao dia; indivíduos jovens apresentaram decréscimo no percentual da cabeça, da altura do focinho e do tronco em relação ao comprimento padrão, com a idade. Durante a fase planctônica, os jovens exibiram cauda em processo de crescimento, pigmentação discreta e nadadeiras peitorais implantadas próximas à base da cabeça. Após este período, a estrutura corporal tornou-se mais sólida e cores de base variadas tornaram-se evidenciadas (aos 2,59 cm); o focinho tornou-se mais alongado e as nadadeiras peitorais passaram a se posicionar próximo à linha das órbitas.Ontogenetic studies constitute an important step to increase the knowledgebase about shifts in food preference and micro-habitats, as well as for improving taxonomy, production for aquaculture, and fisheries management; they may also shed new light on the implications of the extraction of a high volume of animals for trade. This study aimed to estimate the initial growth of the seahorse Hippocampus reidi, and to morphologically describe its ontogeny, from the embryonic period to the reproductive phase. Both aspects are relevant in face of (1) the morphological and biological singularities of the genus, including the ability to bend the body and the body covering formed by bony rings, a Prehensile Tail and the development of a pouch in males and (2) the need to increase our understanding of the biology and ecology of seahorses, a group globally threatened by overfishing and habitat loss. Growth was estimated using ex-situ data obtained from two different broods of H. reidi, while description of the ontogeny was done using data collected both in-situ and ex situ. Data were grouped into two distinct phases: planktonic and postplanktonic (when juveniles are able to use holdfasts). The main results obtained in the study are: H. reidi exhibited an initial daily growth rate of 0.017 cm; juveniles showed a decrease in the percentage of the head, and in the depth of the snout and trunk in relation to standard length with age. During the planktonic phase, juveniles exhibited a a positive growth in the Tail region, weak pigmentation and had the pectoral fins positioned near the base of the head. After that period, the body acquired a more solid structure, and various base became evident (at 2.59 cm); the snout became more elongated, and the pectoral fins were positioned near the level of the orbits
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Descrição morfológica da ontogenia de Hippocampus reidi Ginsburg, 1933 (Teleostei, Syngnathidae): período embrionário à fase reprodutiva
'Portal de Periodicos UFPB', 2010Co-Authors: Júlia Roberta Sá PontesAbstract:Ontogenetic studies constitute an important step to increase the knowledgebase about shifts in food preference and micro-habitats, as well as for improving taxonomy, production for aquaculture, and fisheries management; they may also shed new light on the implications of the extraction of a high volume of animals for trade. This study aimed to estimate the initial growth of the seahorse Hippocampus reidi, and to morphologically describe its ontogeny, from the embryonic period to the reproductive phase. Both aspects are relevant in face of (1) the morphological and biological singularities of the genus, including the ability to bend the body and the body covering formed by bony rings, a Prehensile Tail and the development of a pouch in males and (2) the need to increase our understanding of the biology and ecology of seahorses, a group globally threatened by overfishing and habitat loss. Growth was estimated using ex-situ data obtained from two different broods of H. reidi, while description of the ontogeny was done using data collected both in-situ and ex situ. Data were grouped into two distinct phases: planktonic and postplanktonic (when juveniles are able to use holdfasts). The main results obtained in the study are: H. reidi exhibited an initial daily growth rate of 0.017 cm; juveniles showed a decrease in the percentage of the head, and in the depth of the snout and trunk in relation to standard length with age. During the planktonic phase, juveniles exhibited a a positive growth in the Tail region, weak pigmentation and had the pectoral fins positioned near the base of the head. After that period, the body acquired a more solid structure, and various base became evident (at 2.59 cm); the snout became more elongated, and the pectoral fins were positioned near the level of the orbits.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPESEstudos acerca da ontogenia constituem uma etapa importante para ampliar o entendimento sobre mudanças na preferência alimentar e por micro-habitats, bem como para o aprimoramento da taxonomia, otimização da produção em s e l e ; a r i e u q s e p o ã t s e g a a r a p e a r u t l u c i u q a a m u r a i c i p o r p m e d o p m é b m a t maior compreensão acerca das implicações da extração de um alto volume de animais para o comércio. O presente trabalho buscou estimar o crescimento inicial da espécie de cavalo-marinho Hippocampus reidi e descrever morfologicamente sua ontogenia, do período embrionário à fase reprodutiva. Ambos aspectos são relevantes face às (1) singularidades morfológicas e biológicas do gênero, que incluem a capacidade de dobrar o corpo dorsoventralmente e a presença de placas ósseas dispostas em forma de anel ao longo do corpo, a cauda preênsil e o desenvolvimento de uma bolsa incubadora nos machos e (2) à necessidade de ampliar o conhecimento acerca da biologia e ecologia dos cavalos-marinhos, um grupo globalmente ameaçado pela sobrepesca e pela perda de habitat. Para a análise de crescimento, foram obtidos dados ex-situ de duas diferentes proles de H. reidi. A descrição ontogenética foi realizada utilizando-se dados obtidos in-situ e ex-situ . Foram consideradas duas fases distintas: planctônica e pós-planctônica (quando os jovens são capazes de se prender a estruturas de apoio). Principais resultados obtidos no estudo: H. reidi apresentou uma taxa de crescimento inicial de 0,017 cm ao dia; indivíduos jovens apresentaram decréscimo no percentual da cabeça, da altura do focinho e do tronco em relação ao comprimento padrão, com a idade. Durante a fase planctônica, os jovens exibiram cauda em processo de crescimento, pigmentação discreta e nadadeiras peitorais implantadas próximas à base da cabeça. Após este período, a estrutura corporal tornou-se mais sólida e cores de base variadas tornaram-se evidenciadas (aos 2,59 cm); o focinho tornou-se mais alongado e as nadadeiras peitorais passaram a se posicionar próximo à linha das órbitas
Dominique Adriaens - One of the best experts on this subject based on the ideXlab platform.
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do substrate type and gap distance impact gap bridging strategies in arboreal chameleons
bioRxiv, 2020Co-Authors: Allison M Luger, Vincent Vermeylen, Anthony Herrel, Dominique AdriaensAbstract:Chameleons are well-equipped for an arboreal lifestyle, having zygodactylous hands and feet as well as a fully Prehensile Tail. However, to what degree Tail use is preferred over autopod prehension has not been studied to date. Using an experimental set-up, where chameleons had to cross gaps of varying distances, we tested the effect of substrate diameter and type on Tail use in Chamaeleo calyptratus. Our results show that when crossing greater distances, C. calyptratus is more likely to use its Tail for additional stability. The animals were able to cross greater distances (up to 1.75 times the shoulder-hip length) on perches with a rougher material. We saw that depending on the distance of the gap, chameleons would change their crossing strategy on how they use their Prehensile Tails. With shorter gaps the Tails either do not or only touch the perch without coiling around it. With larger distances the Tails are fully coiled, and with the largest distances the Tails are fully coiled around the perch and after repositioning the hind legs, shifted towards the end of the perch. Males were able to cross relatively greater distances than females, likely due to their larger size and strength. Summary statementChameleons use their Prehensile Tail more often when crossing greater distances and switch strategies on when and how they use their Tails. Males are able to cross relatively greater distances than females.
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comparative developmental osteology of the seahorse skeleton reveals heterochrony amongst hippocampus sp and progressive caudal fin loss
Evodevo, 2014Co-Authors: Tamara A Franzodendaal, Dominique AdriaensAbstract:Seahorses are well known for their highly derived head shape, Prehensile Tail and armoured body. They belong to the family of teleosts known as Syngnathidae, which also includes the pipefishes, pipehorses and seadragons. Very few studies have investigated the development of the skeleton of seahorses because larvae are extremely difficult to obtain in the wild and breeding in captivity is rarely successful. Here we compare the developmental osteology of Hippocampus reidi over an ontogenetic series spanning the first 93 days after release from the brood pouch to that of a smaller series of Hippocampus; namely H. subelongatus. We compare the osteology in these two species over growth to the published description of the dwarf species, H. zosterae. We show that ossification onset in H. subelongatus is earlier than in H. reidi, despite similar sizes at parturition. Interestingly, the timing of development of the bony skeleton in H. zosterae is similar to that of the larger species, H. subelongatus. Furthermore, we show that the growth rate of all three species is similar up until about 30 days post pouch release. From this stage onwards in the life history, the size of the dwarf species H. zosterae remains relatively constant whilst the other two species continue growing with an accelerated growth phase. This data together with a phylogenetic assessment suggests that there has been a heterochronic shift (a delay) in the timing of ossification in H. reidi and accelerated bonedevelopment in H. zosterae. That is, H. zosterae is not a developmentally truncated dwarf species but rather a smaller version of its larger ancestor, “a proportioned dwarf” species. Furthermore, we show that caudal fin loss is incomplete in Hippocampus seahorses. This study shows that these three species of Hippocampus seahorses have evolved (either directly or indirectly) different osteogenic strategies over the last 20–30 million years of seahorse evolution.
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Virtual design from nature : kinematic modeling of the seahorse Tail
2010 SIMULIA Customer Conference Proceedings, 2010Co-Authors: Sofie Van Cauter, Srikanth Kannan, Srikanth Srigiriraju, Tomas Praet, Matthieu De Beule, Bert Masschaele, Dominique Adriaens, Benedict VerheggheAbstract:Seahorses (belonging to the genus Hippocampus) and pipehorses are unique among fishes in being armed with robust body plates instead of scales, and in being able to bend their Tail ventrally for use as a Prehensile appendage. They lack a powerful caudal fin, making them very slow swimmers, which can hardly escape predatory fish. However, they have survived millions of years of natural selection, yielding a very well camouflaged fish with a highly specialized caudal skeleton. This skeleton consists of a central axis of articulating vertebrae, surrounded by jointed bony rings. The stiff bony plates form an armor, which likely makes the fish strongly resistant to bites and unappetizing for predators. However, the adaptive nature of the articulated segments may also be in relation to the formation of the flexible, Prehensile Tail, which can roll up ventrally over more than 360 degrees and enables the seahorse to grasp and hold onto a support. The Tail bending mechanism of seahorses has been studied superficially in literature, but deTails of its functioning and constructional morphology are lacking. To gain a profound insight into the kinematics and mechanical interactions of the skeletal elements of the Tail, the musculoskeletal system is modeled, combining pyFormex with Abaqus, using various features such as beam connectors (bony plates and vertebrae), cartesian, cardan and slot connectors (joints) and axial connectors (muscles). Such modeling may allow the design of nature-inspired structures, providing innovative solutions in engineering where high stiffness combined with high flexibility is needed.
Tamara A Franzodendaal - One of the best experts on this subject based on the ideXlab platform.
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comparative developmental osteology of the seahorse skeleton reveals heterochrony amongst hippocampus sp and progressive caudal fin loss
Evodevo, 2014Co-Authors: Tamara A Franzodendaal, Dominique AdriaensAbstract:Seahorses are well known for their highly derived head shape, Prehensile Tail and armoured body. They belong to the family of teleosts known as Syngnathidae, which also includes the pipefishes, pipehorses and seadragons. Very few studies have investigated the development of the skeleton of seahorses because larvae are extremely difficult to obtain in the wild and breeding in captivity is rarely successful. Here we compare the developmental osteology of Hippocampus reidi over an ontogenetic series spanning the first 93 days after release from the brood pouch to that of a smaller series of Hippocampus; namely H. subelongatus. We compare the osteology in these two species over growth to the published description of the dwarf species, H. zosterae. We show that ossification onset in H. subelongatus is earlier than in H. reidi, despite similar sizes at parturition. Interestingly, the timing of development of the bony skeleton in H. zosterae is similar to that of the larger species, H. subelongatus. Furthermore, we show that the growth rate of all three species is similar up until about 30 days post pouch release. From this stage onwards in the life history, the size of the dwarf species H. zosterae remains relatively constant whilst the other two species continue growing with an accelerated growth phase. This data together with a phylogenetic assessment suggests that there has been a heterochronic shift (a delay) in the timing of ossification in H. reidi and accelerated bonedevelopment in H. zosterae. That is, H. zosterae is not a developmentally truncated dwarf species but rather a smaller version of its larger ancestor, “a proportioned dwarf” species. Furthermore, we show that caudal fin loss is incomplete in Hippocampus seahorses. This study shows that these three species of Hippocampus seahorses have evolved (either directly or indirectly) different osteogenic strategies over the last 20–30 million years of seahorse evolution.
Paul A. Trainor - One of the best experts on this subject based on the ideXlab platform.
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The transcriptome of the veiled chameleon (Chamaeleo calyptratus): A resource for studying the evolution and development of vertebrates
Developmental dynamics : an official publication of the American Association of Anatomists, 2019Co-Authors: Brendan J. Pinto, Raul E. Diaz, Paul A. Trainor, Daren C. Card, Todd A. Castoe, Stuart V. Nielsen, Tony GambleAbstract:Purpose The veiled chameleon (Chamaeleo calyptratus) is an emerging model system for studying functional morphology and evolutionary developmental biology (evo-devo). Chameleons possess body plans that are highly adapted to an arboreal life style, featuring laterally compressed bodies, split hands/ft for grasping, a projectile tongue, turreted independently moving eyes, and a Prehensile Tail. Despite being one of the most phenotypically divergent clades of tetrapods, genomic resources for chameleons are severely lacking. Methods To address this lack of resources, we used RNAseq to generate 288 million raw Illumina sequence reads from four adult tissues (male and female eyes and gonads) and whole embryos at three distinct developmental stages. We used these data to assemble a largely complete de novo transcriptome consisting of only 82 952 transcripts. In addition, a majority of assembled transcripts (67%) were successfully annotated. Results We then demonstrated the utility of these data in the context of studying visual system evolution by examining the content of veiled chameleon opsin genes to show that chameleons possess all five ancestral tetrapod opsins. Conclusion We present this de novo, annotated, multi-tissue transcriptome assembly for the Veiled Chameleon, Chamaeleo calyptratus, as a resource to address a range of evolutionary and developmental questions. The associated raw reads and final annotated transcriptome assembly are freely available for use on NCBI and Figshare, respectively.
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The Veiled Chameleon (Chamaeleo calyptratus Duméril and Duméril 1851): A Model for Studying Reptile Body Plan Development and Evolution
Cold Spring Harbor protocols, 2015Co-Authors: Raul E. Diaz, Christopher V. Anderson, Diana P. Baumann, Richard Kupronis, David Jewell, Christina Piraquive, Jill Kupronis, Kristy Winter, Federica Bertocchini, Paul A. TrainorAbstract:Vertebrate model organisms have facilitated the discovery and exploration of morphogenetic events and developmental pathways that underpin normal and pathological embryological events. In contrast to amniotes such as Mus musculus (Mammalia) and Gallus gallus (Aves), our understanding of early patterning and developmental events in reptiles (particularly nonavians) remains weak. Squamate reptiles (lizards, snakes, and amphisbaenians) comprise approximately one-third of all living amniotes. But studies of early squamate development have been limited because, in most members of this lineage, embryo development at the time of oviposition is very advanced (limb bud stages and older). In many cases, squamates give birth to fully developed offspring. However, in the veiled chameleon (Chamaeleo calyptratus), embryos have progressed only to a primitive pregastrula stage at the time of oviposition. Furthermore, the body plan of the veiled chameleon is highly specialized for climbing in an arboreal environment. It possesses an entire suite of skeletal and soft anatomical modifications, including cranioskeletal ornamentation, lingual anatomy and biomechanics for projection, autopodial clefting for grasping, adaptations for rapid integumental color changes, a Prehensile Tail with a lack of caudal autotomy, the loss of the tympanum in the middle ear, and the acquisition of turreted eyes. Thus, C. calyptratus is an important model organism for studying the role of ecological niche specialization, as well as genetic and morphological evolution within an adaptive framework. More importantly, this species is easily bred in captivity, with only a small colony (
Raul E. Diaz - One of the best experts on this subject based on the ideXlab platform.
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The transcriptome of the veiled chameleon (Chamaeleo calyptratus): A resource for studying the evolution and development of vertebrates
Developmental dynamics : an official publication of the American Association of Anatomists, 2019Co-Authors: Brendan J. Pinto, Raul E. Diaz, Paul A. Trainor, Daren C. Card, Todd A. Castoe, Stuart V. Nielsen, Tony GambleAbstract:Purpose The veiled chameleon (Chamaeleo calyptratus) is an emerging model system for studying functional morphology and evolutionary developmental biology (evo-devo). Chameleons possess body plans that are highly adapted to an arboreal life style, featuring laterally compressed bodies, split hands/ft for grasping, a projectile tongue, turreted independently moving eyes, and a Prehensile Tail. Despite being one of the most phenotypically divergent clades of tetrapods, genomic resources for chameleons are severely lacking. Methods To address this lack of resources, we used RNAseq to generate 288 million raw Illumina sequence reads from four adult tissues (male and female eyes and gonads) and whole embryos at three distinct developmental stages. We used these data to assemble a largely complete de novo transcriptome consisting of only 82 952 transcripts. In addition, a majority of assembled transcripts (67%) were successfully annotated. Results We then demonstrated the utility of these data in the context of studying visual system evolution by examining the content of veiled chameleon opsin genes to show that chameleons possess all five ancestral tetrapod opsins. Conclusion We present this de novo, annotated, multi-tissue transcriptome assembly for the Veiled Chameleon, Chamaeleo calyptratus, as a resource to address a range of evolutionary and developmental questions. The associated raw reads and final annotated transcriptome assembly are freely available for use on NCBI and Figshare, respectively.
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The Veiled Chameleon (Chamaeleo calyptratus Duméril and Duméril 1851): A Model for Studying Reptile Body Plan Development and Evolution
Cold Spring Harbor protocols, 2015Co-Authors: Raul E. Diaz, Christopher V. Anderson, Diana P. Baumann, Richard Kupronis, David Jewell, Christina Piraquive, Jill Kupronis, Kristy Winter, Federica Bertocchini, Paul A. TrainorAbstract:Vertebrate model organisms have facilitated the discovery and exploration of morphogenetic events and developmental pathways that underpin normal and pathological embryological events. In contrast to amniotes such as Mus musculus (Mammalia) and Gallus gallus (Aves), our understanding of early patterning and developmental events in reptiles (particularly nonavians) remains weak. Squamate reptiles (lizards, snakes, and amphisbaenians) comprise approximately one-third of all living amniotes. But studies of early squamate development have been limited because, in most members of this lineage, embryo development at the time of oviposition is very advanced (limb bud stages and older). In many cases, squamates give birth to fully developed offspring. However, in the veiled chameleon (Chamaeleo calyptratus), embryos have progressed only to a primitive pregastrula stage at the time of oviposition. Furthermore, the body plan of the veiled chameleon is highly specialized for climbing in an arboreal environment. It possesses an entire suite of skeletal and soft anatomical modifications, including cranioskeletal ornamentation, lingual anatomy and biomechanics for projection, autopodial clefting for grasping, adaptations for rapid integumental color changes, a Prehensile Tail with a lack of caudal autotomy, the loss of the tympanum in the middle ear, and the acquisition of turreted eyes. Thus, C. calyptratus is an important model organism for studying the role of ecological niche specialization, as well as genetic and morphological evolution within an adaptive framework. More importantly, this species is easily bred in captivity, with only a small colony (
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the veiled chameleon chamaeleo calyptratus dumeril and dumeril 1851 a model for studying reptile body plan development and evolution
CSH Protocols, 2015Co-Authors: Raul E. Diaz, Christopher V. Anderson, Diana P. Baumann, Richard Kupronis, David Jewell, Christina Piraquive, Jill Kupronis, Kristy Winter, Federica BertocchiniAbstract:Vertebrate model organisms have facilitated the discovery and exploration of morphogenetic events and developmental pathways that underpin normal and pathological embryological events. In contrast to amniotes such as Mus musculus (Mammalia) and Gallus gallus (Aves), our understanding of early patterning and developmental events in reptiles (particularly nonavians) remains weak. Squamate reptiles (lizards, snakes, and amphisbaenians) comprise approximately one-third of all living amniotes. But studies of early squamate development have been limited because, in most members of this lineage, embryo development at the time of oviposition is very advanced (limb bud stages and older). In many cases, squamates give birth to fully developed offspring. However, in the veiled chameleon (Chamaeleo calyptratus), embryos have progressed only to a primitive pregastrula stage at the time of oviposition. Furthermore, the body plan of the veiled chameleon is highly specialized for climbing in an arboreal environment. It possesses an entire suite of skeletal and soft anatomical modifications, including cranioskeletal ornamentation, lingual anatomy and biomechanics for projection, autopodial clefting for grasping, adaptations for rapid integumental color changes, a Prehensile Tail with a lack of caudal autotomy, the loss of the tympanum in the middle ear, and the acquisition of turreted eyes. Thus, C. calyptratus is an important model organism for studying the role of ecological niche specialization, as well as genetic and morphological evolution within an adaptive framework. More importantly, this species is easily bred in captivity, with only a small colony (<10 individuals) needed to obtain hundreds of embryos every year.