Filogenia e evolução de ouriços-cacheiros (Rodentia:Erethizontidae)

• Autor(a) principal: Caldara Junior, Vilacio
• Data de Publicação: 2013
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/4360
• topic: Development; Character mapping; Morphometrics; Systematics; Morfometria; Desenvolvimento; Mapeamento de caracteres; Sistemática; Coendou; Zoologia; Caracteres e características; 57

Erethizontidae is the family of rodents known as the New World porcupines. There are controversies about their taxonomy, especially regarding genera and species. The phylogenetic relationships among Erethizontidae species are poorly known and the evolution of their most striking features remains a puzzle. The main goal of this study was to assess the evolution of Erethizontidae based on a phylogeny of 9 out of 15 porcupine species. We performed phylogenetic inferences on a mitochondrial and a nuclear gene, analyses of morphological and morphometric characters from skin and skull, analyses of postnatal development and character mapping on the phylogeny and inferences on the processes involved in phenotypic evolution of Erethizontidae. The resulting phylogenies confirmed the monophyly of the family Erethizontidae, the subfamily Erethizontinae and the genus Coendou. In this genus, Co. prehensilis is sister to smaller Coendou species, followed by Co. melanurus and then Co. roosmalenorum. Coendou nycthemera grouped with Coendou sp. in a clade that grouped with another containing Co. insidiosus and Co. spinosus, which are not reciprocally monophyletic. The phylogeny does not corroborate grouping some species of Coendou in the genus Sphiggurus, as recognized by some authors, because neither would be monophyletic. Skull characters and measurements are more effective than external characters in distinguishing Co. prehensilis from the clade of smaller Coendou. External characters and some morphometric variables worked better in diagnosing smaller Coendou species. The data confirms the existence of an apparently new species of porcupine, and the need to synonymize Co. spinosus and Co. insidiosus. The skull of smaller species of Erethizontidae changes little during their growth, but larger species undergo major skull transformation, while the dorsal fur is quite altered during development in almost all species. The most probable ancestral states in skin characters varied at different phylogeny levels, while on cranial characters, the states found in young 4 and smaller species are the most likely in almost all species. The most important process acting on porcupine phenotypic evolution was genetic drift, especially early in the diversification of this group (reflecting on today’s species groups, genera or subfamilies), but natural selection (mainly directional or disruptive) was more influential on the evolution of current specie