Geographic variation in the advertisement calls of Gekko gecko in relation to variations in morphological features: implications for regional population differentiation

TLDR: The tokay gecko complex has become differentiated geographically not only in terms of morphological characteristics but also in Terms of call acoustics.

Abstract: Geographic variations in vocalizations and morphological characteristics of the tokay gecko (Gekko gecko L.) complex were identified using subjects recorded and/or collected in China and Southeast Asia. Populations in south China and northeast Vietnam (the black tokay) were compared with those in Thailand, Laos and south Vietnam (the red tokay). Red tokays possess gray- or dark green-colored skin with brick red spots interspersed on the dorsum, while black tokays possess dark-green skin with black spots or spots of other colors except brick red. Each group produces advertisement calls which consist of distinct acoustic phases. In both groups the first call phase consists of a series of pulses and the second phase consists of a series of two-note syllables. Only red tokays produce a third phase consisting of single notes. Frequency modulation patterns were profoundly different for call elements produced between the two groups. Calls of the black but not red tokay exhibit intricate frequency modulated eleme...