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1.
Genetica ; 150(6): 367-377, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36229707

RESUMO

The Brazilian Cerrado is considered a biodiversity hotspot highly threatened by human activities. Recently, many studies have demonstrated how underestimated is Cerrado's biodiversity considering squamate species, and the identification of divergent and cryptic lineages is essential for the formulation of effective conservation strategies. The transition areas between the Cerrado and the Atlantic Forest are even less known and, consequently, often dismissed in conservation policies. As previous studies suggested the presence of cryptic diversity within E. capetinga, we investigated patterns and processes in the geographic distribution of its genealogical lineages. We used DNA sequences from individuals collected in six localities and sequences publicly available from three mitochondrial markers (CYT-B, 16S and ND4) and one nuclear marker (C-Mos). We tested if the core and ecotone regions of the Cerrado show differences in biotic and abiotic characteristics that could promote genetic structure and divergence among lineages within E. capetinga. We found evidence for divergent lineages within the species, but not congruent with our hypothesis. Similar divergent patterns were observed in other Cerrado lizards, including interspecific divergences within the Enyalius genus. Molecular characterization of field-collected individuals (previously identified as E. bilineatus), allowed us to update the geographic distribution of the species to include the ecotone between the Cerrado and the Atlantic Forest, an area where species distribution overlap.


Assuntos
Lagartos , Humanos , Animais , Lagartos/genética , Florestas , Biodiversidade , Estruturas Genéticas , Brasil , Filogenia
2.
Braz J Biol ; 75(3): 535-40, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26465721

RESUMO

Human behavior toward wild animals is defined by cultural influences and often is affected by lack of knowledge, mainly in situations of confrontation. The present study was conducted between 2008 and 2013, involving analysis of snakes that had suffered injuries belonging to the reptile collections of Centro Universitário de Lavras and Universidade Federal de Juiz de Fora. The injuries were classified according to location on the body. Among the 449 specimens analyzed, 245 specimens showed injury to some part of the body. The nonvenomous snakes were the most representative and had a higher rate of injury (66.3%) than the venomous ones (18.2%). The body region where the greatest percentage of injuries was recorded was the anterior (39.6%), followed by the middle (36.5%) and posterior (8.4%). We believe this fact may have resulted due the lack of knowledge on how to differentiate species. Studies of the relationship between schooling level and contact with environmental education activities demonstrate reduction of attacks on these animals. This fact indicates that the preservation of many species is related to awareness and education of the population.


Assuntos
Serpentes/lesões , Animais , Brasil , Humanos
3.
Braz. J. Biol. ; 75(3): 535-540, Aug. 2015. tab
Artigo em Inglês | VETINDEX | ID: vti-341470

RESUMO

Human behavior toward wild animals is defined by cultural influences and often is affected by lack of knowledge, mainly in situations of confrontation. The present study was conducted between 2008 and 2013, involving analysis of snakes that had suffered injuries belonging to the reptile collections of Centro Universitário de Lavras and Universidade Federal de Juiz de Fora. The injuries were classified according to location on the body. Among the 449 specimens analyzed, 245 specimens showed injury to some part of the body. The nonvenomous snakes were the most representative and had a higher rate of injury (66.3%) than the venomous ones (18.2%). The body region where the greatest percentage of injuries was recorded was the anterior (39.6%), followed by the middle (36.5%) and posterior (8.4%). We believe this fact may have resulted due the lack of knowledge on how to differentiate species. Studies of the relationship between schooling level and contact with environmental education activities demonstrate reduction of attacks on these animals. This fact indicates that the preservation of many species is related to awareness and education of the population.(AU)


O comportamento humano para com os animais selvagens é definido por influências culturais e muitas vezes é afetado por falta de conhecimento, principalmente em situações de confronto. Podendo levar à matança indiscriminada, consequentemente a um estado de declínio. O presente estudo foi realizado entre 2008 e 2013, envolvendo a análise de serpente que sofreram lesões pertencentes às coleções de répteis do Centro Universitário de Lavras e Universidade Federal de Juiz de Fora. As lesões foram classificadas de acordo com a localização no corpo. Entre os 449 espécimes analisados, 245 mostram lesões. As serpentes não peçonhentas foram as mais representativas e apresentaram uma maior taxa de lesão (66,3%) do que os peçonhentos (18,2%). A região do corpo onde ocorreu a maior percentagem de lesões registada foi a anterior (39,6%), seguido pelo meio (36,5%) e posterior (8,4%). Acreditamos que este fato pode ter resultado devido a falta de conhecimento sobre como diferenciar espécies. Estudos sobre a relação entre nível de escolaridade e contato com atividades de educação ambiental demonstram redução dos ataques a esses animais. Este fato indica que a preservação de muitas espécies está relacionado à conscientização e educação da população.(AU)


Assuntos
Humanos , Animais , Serpentes/lesões , Conservação dos Recursos Naturais , Educação em Saúde Ambiental , Brasil
4.
Braz. J. Biol. ; 74(4): 977-982, 11/2014. graf
Artigo em Inglês | VETINDEX | ID: vti-13671

RESUMO

A type of locomotor behavior observed in animals with rigid bodies, that can be found in many animals with exoskeletons, shells, or other forms of body armor, to change direction, is the turning behavior. Aquatic floated-turning behavior among rigid bodies animals have been studied in whirligig beetles, boxfish, and more recently in freshwater turtle, Chrysemys picta. In the laboratory we observed a different kind of turning movement that consists in an underwater turning movement during foraging, wherein the animal pivoted its body, using one of the hindlimbs as the fixed-point support in the substratum. We describe, analyze and quantify this movement during foraging in Hydromedusa maximiliani, using observations made in the laboratory. We studied 3 adult specimens (2 males, 1 female) and 2 non-sexed juveniles of H. maximiliani. They were kept individually in an aquarium filled with water and small fish. They were filmed, in dorsal view, at 30 frames per second. Sequences were analyzed frame by frame and points were marked on limbs and shell to enable analysis of variation in limb flexion and extension, as well as rotation movements. While foraging, turtles frequently turned their bodies, using one hind leg as the pivot point. This underwater turning movement, in addition to slow movements with the neck stretched, or staying nearly immobile and scanning the surroundings with lateral movements of the neck (in arcs up to 180°), and fast attacks of neck, may increase prey capture rates.(AU)


Um tipo de comportamento locomotor observado em animais com corpo rígido, que pode ser encontrado em muitos animais com exoesqueleto, conchas, ou outras formas de armaduras, para mudar de direção, é o girar o corpo num plano horizontal (Turning performance). O movimento de girar o corpo flutuando na água (Aquatic floated-turning performance) entre animais de corpo rígido tem sido estudado em besouros, peixe-caixa, e mais recente na tartaruga de água doce, Chrysemys picta. No laboratório nós observamos um tipo diferente de giro que consiste em um giro subaquático, não flutuando na água, durante o forrageio, onde o animal pivota seu corpo, usando uma das patas traseiras como um ponto fixo de suporte no substrato. Nós descrevemos, analisamos e quantificamos esse movimento durante o forrageio de Hydromedusa maximiliani, usando observações feitas em laboratório. Nós analisamos três adultos (2 machos, 1 fêmea) e dois juvenis não sexados. Eles foram mantidos individualmente em um aquário preenchido água e pequenos peixes. Eles foram filmados, em vista dorsal, a 30 imagens por segundo. As sequencias foram analisadas quadro a quadro, e pontos foram marcados nos membros e no casco para permitir analisar variações angulares durante a flexão e extensão, bem como movimentos de rotação. Os membros fizeram movimentos sequencias durante o movimento de giro, mantendo sempre um dos membros posteriores como ponto fixo. Esta estratégia de forrageio associada com movimentos lentos e pescoço esticado, ou permanecer praticamente imóveis apenas observando o ambiente através de movimentos laterais do pescoço, descrevendo trajetórias em um ângulo de 180°, e ataques rápidos com o pescoço, talvez aumente seu potencial na captura de presas.(AU)


Assuntos
Animais , Masculino , Feminino , Movimento/fisiologia , Comportamento Predatório/fisiologia , Tartarugas/fisiologia , Peixes , Água Doce
5.
Braz J Biol ; 74(4): 977-82, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25627611

RESUMO

A type of locomotor behavior observed in animals with rigid bodies, that can be found in many animals with exoskeletons, shells, or other forms of body armor, to change direction, is the turning behavior. Aquatic floated-turning behavior among rigid bodies animals have been studied in whirligig beetles, boxfish, and more recently in freshwater turtle, Chrysemys picta. In the laboratory we observed a different kind of turning movement that consists in an underwater turning movement during foraging, wherein the animal pivoted its body, using one of the hindlimbs as the fixed-point support in the substratum. We describe, analyze and quantify this movement during foraging in Hydromedusa maximiliani, using observations made in the laboratory. We studied 3 adult specimens (2 males, 1 female) and 2 non-sexed juveniles of H. maximiliani. They were kept individually in an aquarium filled with water and small fish. They were filmed, in dorsal view, at 30 frames per second. Sequences were analyzed frame by frame and points were marked on limbs and shell to enable analysis of variation in limb flexion and extension, as well as rotation movements. While foraging, turtles frequently turned their bodies, using one hind leg as the pivot point. This underwater turning movement, in addition to slow movements with the neck stretched, or staying nearly immobile and scanning the surroundings with lateral movements of the neck (in arcs up to 180°), and fast attacks of neck, may increase prey capture rates.


Assuntos
Movimento/fisiologia , Comportamento Predatório/fisiologia , Tartarugas/fisiologia , Animais , Feminino , Peixes , Água Doce , Masculino
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