An Electrophoretic Analysis of Holarctic Hylid Frog Evolution
1986; Oxford University Press; Volume: 35; Issue: 1 Linguagem: Inglês
10.1093/sysbio/35.1.1
ISSN1076-836X
Autores Tópico(s)Genetic diversity and population structure
ResumoThe phylogenetic relationships of 30 taxa of Holarctic hylid frogs were examined using starch gel electrophoresis. Allelic variation was scored at 33 presumed genetic loci and genetic distance data were used to construct trees representing the phylogenetic relationships. There are two major groups: (A) Hyla regilla, H. cadaverina, H. crucifer, Limnaoedus ocularis, and all presently recognized species of Pseudacris; and (B) the remaining species of Holarctic Hyla.The positions of Acris and H. meridionalis are unclear. In general, the relationships based on electrophoretic data agree well with immunological, hybridization, and chromosome studies, but conflict with some morphological studies. A phylogenetic classification requires that H. regilla, H. cadaverina, H. crucifer, and L. ocularis be transferred to the genus Pseudacris. This genus is characterized by terrestrial species that breed during cold weather and possess small digital pads and spherical (or ovoid) dark testes. Holarctic Hyla are arboreal species that breed during warm weather and possess large digital pads and elongate white (or yellowish) testes. The correlation between albumin immunological distance (AID) and Nei's electrophoretic distance (D) is significant, with 1 D = 70 AID. Calibration of the molecular clock for Holarctic hylid frogs suggests that Pseudacris diverged from a Hyla-like ancestor in the early Tertiary. The physiological traits associated with cold-weather breeding and the morphological trait (small digital pads) associated with terrestrial habits appear to have been key innovations that allowed Pseudacris to undergo an adaptive radiation in North America coinciding with the radiation of Holarctic Hyla.
Referência(s)