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Universidade Do Estado Do Rio De Janeiro Centro Biomédico Instituto De Biologia Roberto Alcantara Gomes Universidade do Estado do Rio de Janeiro Centro Biomédico Instituto de Biologia Roberto Alcantara Gomes Thiago Maia Ney Carneiro Ecologia de duas espécies de lagarto cogenéricas (Squamata, Tropidurus) em simpatria em uma área do semiárido no nordeste do Brasil Rio de Janeiro 2016 Thiago Maia Ney Carneiro Ecologia de duas espécies de lagarto cogenéricas (Squamata, Tropidurus) em simpatria em uma área do semiárido no nordeste do Brasil Tese apresentada, como requisito parcial para obtenção do título de Doutor, ao Programa de Pós-Graduação em Ecologia e Evolução da Universidade do Estado do Rio de Janeiro Orientador: Prof. Dr. Carlos Frederico Duarte da Rocha Rio de Janeiro 2016 CATALOGAÇÃO NA FONTE UERJ / REDE SIRIUS / BIBLIOTECA CTC/A C289 Carneiro, Thiago Maia Ney. Ecologia de duas espécies de lagarto cogenéricas (Squamata, Tropidurus) em simpatia em uma área do semiárido no nordeste do Brasil. – 2016. 267f. : il. Orientador: Carlos Frederico Duarte da Rocha Tese (Doutorado) - Universidade do Estado do Rio de Janeiro, Instituto de Biologia Roberto Alcantara Gomes. 1. Lagarto – Brasil, Nordeste - Teses. 2. Lagarto - Ecologia - Teses I. Rocha, Carlos Frederico Duarte da. II. Universidade do Estado do Rio de Janeiro. Instituto de Biologia Roberto Alcântara Gomes. III. Título. CDU 598.112(81) Autorizo, apenas para fins acadêmicos e científicos, a reprodução total ou parcial desta tese, desde que citada a fonte. _________________________________ ______________________ Assinatura Data Thiago Maia Ney Carneiro Ecologia de duas espécies de lagarto cogenéricas (Squamata, Tropidurus) em simpatria em uma área do semiárido no nordeste do Brasil Tese apresentada, como requisito parcial para obtenção do título de Doutor, ao Programa de Pós-Graduação em Ecologia e Evolução da Universidade do Estado do Rio de Janeiro Aprovado em 26 de fevereiro de 2016 Banca examinadora: ______________________________________________ Prof. Dr. Carlos Frederico Duarte da Rocha (Orientador) Instituto de Biologia Roberto Alcantara Gomes - UERJ ______________________________________________ Prof.ª Dra. Vanderlaine de Amaral Menezes Instituto de Biologia Roberto Alcantara Gomes - UERJ ______________________________________________ Prof. Dr. Davor Vrcibradic Universidade Federal do Estado do Rio de Janeiro _______________________________________________ Prof.ª Dra. Luciana Ardenghi Fusinatto Universidade Federal de São Paulo ___________________________________________ Prof. Dr. Mauricio de Almeida Gomes Universidade Federal do Rio de Janeiro Rio de Janeiro 2016 DEDICATÓRIA À minha família e amigos... AGRADECIMENTOS Muitas pessoas merecem agradecimentos por todos os conselhos, ajuda, paciência, carinho, compreensão e amor que fundamentaram, facilitaram e possibilitaram a minha caminhada ao longo da vida e a realização desta tese. Não poderia deixar de agradecer inicialmente ao meu querido e admirado orientador e amigo Carlos Frederico Duarte da Rocha por tudo o que disse acima e também por sempre acreditar em minha capacidade de realização. Sem dúvida alguma, seus incentivos foram importantíssimos, me motivando em momentos que eu precisava, e fundamentais para a concretização desta tese. Seus ensinamentos, não apenas profissionais, mas também como pessoa, me acompanharão para sempre. Muito obrigado por sua dedicação! À minha família e amigos por terem apoiado a minha trajetória até aqui. Obrigado por tanto que não sei o que dizer de tanto que tenho para falar.... Agradeço também aos amigos de laboratório e de profissão Bia, Carla, Carol, Cátia, Daniel, Davor, Felipe, Gisa, Jane, Leandro, Lili, Lu, Manu, Mara, Marlon, Mauricio, Pathie, Paulo, Rafael, Robson, Tati, Thiago, Vandy e Vitor pelos aprendizados ao longo dos anos de convivência e pelas conversas e ideias interessantes e muitas vezes esclarecedoras e estimulantes. Vocês participaram da construção de momentos e de lembranças felizes e divertidas no laboratório e no campo. Também sou grato aos professores do Programa de Pós- Graduação em Ecologia e Evolução (PPGEE/UERJ) por todo ensinamento e ao pessoal do Departamento de Ecologia e da Secretaria do PPGEE/UERJ por toda a ajuda. Agradeço à Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) e à Fundação Carlos Chagas de Apoio à Pesquisa do Estado do Rio de Janeiro (FAPERJ) pela concessão de bolsas de estudo que permitiram a execução desta tese. De coração, muito obrigado a todos vocês! “A autoconfiança do Guerreiro não é a autoconfiança do homem comum. O homem comum procura certeza aos olhos do observador e chama a isso autoconfiança. O Guerreiro procura impecabilidade aos próprios olhos e chama a isso humildade. O homem comum está preso aos seus semelhantes, enquanto o Guerreiro só está preso ao infinito”. Don Juan Matus RESUMO MAIA-CARNEIRO, Thiago. Ecologia de duas espécies de lagarto cogenéricas (Squamata, Tropidurus) em simpatria em uma área do semiárido no nordeste do Brasil. 2016. 267 f. Tese (Doutorado em Ecologia e Evolução) – Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, 2016. Investigações sobre as dimensões temporais, tróficas e espaciais de nicho de lagartos brasileiros conduzidas no capítulo 1 deste estudo revelaram que espécies filogeneticamente próximas tenderam a se sobrepor mais intensamente na associação a recursos tróficos e espaciais, indicando que fatores históricos prevalecem sobre variações em condições ambientais entre regiões geográficas na determinação da ecologia de cada espécie. Ao longo deste estudo, eu também analisei os nichos temporais (Capítulo 2), tróficos (Capítulo 3) e espaciais (Capítulos 2 e 4), associações ecomorfológicas (Capítulo 5), parasitismo (Capítulo 6) e comportamentos defensivos (Capítulo 7) de Tropidurus hispidus e de T. semiataeniatus vivendo em simpatria em afloramentos rochosos no nordeste do Brasil. As diferenças nas dimensões temporais de nicho não foram as mais relevantes para a coexistência simpátrica de T. hispidus e de T. semitaeniatus, entretanto, estas espécies diferiram substancialmente quanto à utilização do espaço estrutural e térmico, selecionando microambientes adequados aos seus requerimentos fisiológicos, ecológicos e comportamentais. Estes lagartos podem regular ativamente as suas temperaturas corpóreas através do comportamento utilizando as temperaturas do ar e do substrato e a luz solar direta. Tropidurus hispidus e T. semitaeniatus consumiram tipos de alimento similares, principalmente formigas, cupins, besouros adultos e flores, mas diferiram nos tamanhos de alimentos adquiridos. Lagartos T. semitaeniatus mantiveram elevadas temperaturas corpóreas para cumprir requerimentos térmicos relacionados a aquisição e a digestão de alimentos e apresentaram variação ontogenética no consumo de matéria vegetal, com a aquisição de plantas aumentando progressivamente com a idade. Ambas as espécies possuem características morfológicas que capacitam os lagartos para a utilização diferencial de recursos tróficos e espaciais. Novos registros de ocorrência de espécies de helmintos foram realizados para ambas as espécies de lagarto: Piratuba digiticauda em T. hispidus e Oochoristica bresslaui em T. semitaeniatus. O parasitismo por helmintos pode ter causado reações fisiológicas e comportamentais que promoveram limitações nos desempenhos dos lagartos, resultando em diminuições da distância mínima de iniciação de fuga de T. hispidus e da temperatura corpórea de T. semitaeniatus de acordo com o aumento da abundância de parasitas. As dimensões corpóreas de T. hispidus e de T. semitaeniatus influenciaram a ocorrência de diferenças interespecíficas em respostas defensivas (imobilidade e distância mínima de iniciação de fuga) por estes lagartos e as temperaturas do corpo afetaram negativamente as distâncias mínimas de iniciação de fuga de T. hispidus causando restrições quanto a desempenhos locomotores. A morfologia, a ecologia e o comportamento de T. hispidus e de T. semitaeniatus atuaram em sinergia habilitando os indivíduos para a partição de recursos, auxiliando a redução de sobreposições de dimensões de nicho e favorecendo as suas coexistências em simpatria. Palavras-chave: Caatinga. Comportamentos defensivos. Ecologia térmica. Ecomorfologia. Nicho espacial. Nicho temporal. Nicho trófico. Parasitismo. Squamata. Termorregulação. Tropiduridae. ABSTRACT MAIA-CARNEIRO, Thiago. Ecology of two cogeneric lizard species (Squamata, Tropidurus) in sympatry in a semiarid area in northeastern Brazil. 2016. 267 f. Tese (Doutorado em Ecologia e Evolução) – Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, 2016. Investigations regarding temporal, trophic and spatial niche dimensions of Brazilian lizards conducted in the chapter 1 of this study revealed that phylogenetically closely related species tended to overlap more intensely in the association with trophic and spatial resources, indicating that historical factors prevail over variations of environmental conditions among geographic regions in the determination of the ecology of each species. Throughout this study, I also analysed temporal (Chapter 2), trophic (Chapter 3), and spatial (Chapters 2 and 4) niche dimensions, ecomorphological associations (Chapter 5), parasitism (Chapter 6) and defensive behaviours (Chapter 7) of Tropidurus hispidus and of T. semiataeniatus living in sympatry on rock outcrops in northeastern Brazil. Differences in temporal niche dimensions were not the most relevant for the sympatric coexistence of T. hispidus
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