Acoustic Behavior 
289 
Table 1. Some geckos known to produce sounds with comments on the types of sounds produced. 
Subfamily Species Sounds Produced Authority 
Eublepharinae 
Diplodactylinae 
Gekkoninae 
Sphaerodactylinae 
Coleonyx variegatus 
Eublepharis macular is 
Nephrurus asper 
Phyllurus platyurus 
Artistelliger praesignis 
A. nelsoni 
A. lar 
Cyrtodactylus kotschyi 
Gymnodactylus kotschyi 
Gekko geko 
Gekko chinensis 
Hemidactylus brooki 
H. flaviviridis 
H. frenatus 
H. mabouia 
H. turcicus 
Phelsuma madagascarensis 
Phyllodactylus tuberculosus 
Ptenopus garrulus 
P. carpi 
P. kochi 
Ptychozoon kuhli 
Ptyodactylus hasselquistii 
Stenodactylus sthenodactylus 
Thecadactylus rapicauda 
Tropiocolotes steudneri 
Sphaerodactylus sp. 
Squeaks when handled 
ff ff 
Churr when threatened 
ft ft ft 
Multiple chirps + squeak 
ft ft 9f 
ft ft ft 
Squeaks when handled 
Multiple chirps 
Multiple chirps + churr 
Multiple chirps 
Multiple chirps + squeak 
tt tt tt 
" " squeak + 
churr 
" " + squeak 
tt tt tt 
Purring sounds + squeak 
Multiple chirps + squeak 
Multiple chirps 
tt tt 
tt tt 
" " + squeak 
tt tt tt 
Squeaks when handled 
Multiple chirps + squeak 
Squeaks when handled 
Squeaks when handled 
Greenberg, 1943 
Pers. Obs. 
Bustard, 1967b 
Mebs, 1973 
R. Crombie, Pers. Comm. 
tt tt tt tt 
tt tt tt tt 
Y. Werner, Pers, Comm. 
Evans, 1936 
Many investigators 
R. Crombie, Pers. Comm. 
tt tt n tt 
Mahendra, 1936 
Marcellini, 1974 
R. Crombie, Pers. Comm. 
Pers. Obs 
Keepers, NZP 
Pers, Obs. 
Haacke, 1969 
tt tt 
tt tt 
Pers. Obs. 
Frankenberg, 1974 
Y. Wener, Pers. Comm. 
Pers. Obs. 
Y. Werner, Pers. Comm. 
R. Crombie, Pers. Comm. 
of a typical mammalian ear, but within a 
restricted frequency range some species of 
lizards are comparable to many mammals. 
The range of sensitivity in lizards is from 
approximately 100 Hz to 10,000 Hz, and the 
greatest sensitivity is between 100 Hz to 
3000 Hz. Of the lizards studied, the geckos 
Coleonyx and Ptyodactylus were found to 
have the most sensitive hearing. It is im- 
portant to note that some members of other 
families of lizards have ears that are as 
sensitive as some geckos. Crotaphytus 
collaris and Gerrhonotus multicarinatus are 
two such nongekkonid lizards. One of the 
geckos, Colenoyx variegatus, with the most 
sensitive hearing is not very vocal, while the 
unusually vocal tokay gecko {Gekko gecko) 
has an acoustic sensitivity less than half 
that of Coleonyx. Factors other than the 
reception of intraspecific signals are obvi- 
ously involved. For example, sensitive hear- 
ing might be valuable in Coleonyx as a 
mechanism of escaping predators in its 
desert environment. 
Acoustic Behavior of Hemidactylus frenatus 
The data concerning the acoustic behavior 
of H. frenatus have been published in detail 
(Marcellini, 1974). Hemidactylus frenatus 
has a vocal repertory of three functionally 
and physically distinct calls. The multiple- 
chirp call is the most common and is closely 
associated with agonistic behavior and ter- 
ritoriality (Fig. 1). The multiple-chirp has 
a consistent temporal pattern of chirps (Fig. 
2), and the call rate varies directly with air 
temperature. When diel calling periodicity 
was investigated, the calls were observed to 
increase in frequency from dusk to the early 
morning hours (Fig. 3). Increasing call 
