Genetic Variability in Populations of the Giant Toad Bufo marinus Linn.

Abstract

Genetic variability in 289 Philippine giant toads Bufo marinus Linn. from three populations was assayed by starch gel electrophoresis of 8 blood proteins encoded by 12 presumptive loci. Various indices of intrapopulation genetic variation showed the Mindanao toad population to be most variable (P-75%; H=32.25% and A=2.167) followed by the Luzon group (P-66.67%; H=16.27% and A=2.167). The third population, from the Visayas, showed the least variability (P-16.67%; H=8.26% and A=1.5). Estimates of Nei's and Hillis' genetic identity and distance and Hedrick's genotypic identity showed that the Luzon and Mindanao populations share many alleles in common (I=0.9514, 1*=0.9505 and 1=0.8963) and are therefore more closely related. Consequently, greatest genetic divergence exists between the Luzon and Visayas populations.