Evidence for speciational change in the evolution of ratites (Aves: Palaeognathae)

摘要: To perform a comparative analysis of character associations framed in phylogenetic context (e.g. independent contrasts), model evolution must be assumed. According to phyletic gradualism, morphological change accumulates gradually over time within lineages, and speciation events do not have major role. Under speciational models, is assumed occur during or just after cladogenesis both daughter species, the resulting morphologies long periods (stasis), until next cladogenetic event. A novel method presented for comparing these models that uses permutational multiple regressions. The addition divergence times well-corroborated trees utilization developed this paper allows estimation relative frequency gradual from living organisms. This applied dataset ratites with conclusion that, range features, tends been rather than gradual.