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Diniz-Filho, José Alexandre Felizola1; Sant’Ana, Carlos Eduardo Ramos De2
Phylogenetic correlograms and the evolution of body size in South America owls (Strigiformes), Genetics and Molecular Biology, 23, 2, 285-292 (2000)
1Departamento de Biologia
Geral, ICB, Universidade Federal de Goiás, CP. 131, 74001-970, Goiânia, GO, Brazil, e-mail:diniz@icb1.ufg.br
2Centro Federal de Educação Tecnológica (CEFET-GO), 74055-110, Rua 75, no 46, Setor Central, Goiânia, GO, Brazi
Abstract:
During the last few years, many models have been proposed to link microevolutionary processes to macroevolutionary patterns, defined by comparative data analysis. Among these, Brownian motion and
Ornstein-Uhlenbeck (O-U) processes have been used to model, respectively, genetic drift or directional selection and stabilizing selection. These models produce different curves of pair wise variance between species
against time since divergence, in such a way, that different profiles appear in phylogenetic correlograms. We analyzed variation in body length among 19 species of South American owls, by means of phylogenetic
correlograms constructed using Moran’s I coefficient in four distance classes. Phylogeny among species was based on DNA hybridization. The observed correlogram was then compared with 500 correlograms obtained by
simulations of Brownian motion and O-U over the same phylogeny, using discriminant analysis. The observed correlogram indicates a phylogenetic gradient up to 45 mya, when coefficients tend to stabilize, and it is
similar to the correlograms produced by the O-U process. This is expected when the consider that body size of organisms is correlated with many ecological an life-history traits and subjected to many constraints
that can be modeled by the O-U process, which has been used to describe evolution under stabilizing selection.
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