298 
Marcellini 
Table 6. Some significant contributions to the literature on gekkonid acoustic behavior. 
Author and Year 
Taxon 
Findings 
Frankenberg, E. 1974 
Ptyodactylus sp. 
Calls of 3 forms of Ptyodactylus analyzed. 
Calls consisted of a series of clicks. Male to 
male calls differed from male to female calls. 
Gans, C. & Manderson, P.F.A. 1973 
Many reptiles 
Review of literature on reptilia sound produc- 
tion with comments on gecko sound producing 
mechanisms. 
Haacke, W.D. 1969 
Ptenopus sp. 
Calls of 3 species of Ptenopus analyzed and 
each has a different call. Calls consist of a 
series of clicks. Certain populations of some 
species may have more than one type of call. 
Marcellini, D.L. 1974 
Hemidactylus frenatus 
H. Frenatus has three types of calls. Multiple 
chirp, single chirp and churr. These calls ap- 
pear to perform different functions. Call rate 
varies directly with temperature. 
Peterson, E.A. 1966 
Many species both 
gekkonid and non- 
gekkonid 
Hearing sensitivity of 13 species analyzed. 
The lizards with the most sensitive ears were 
generally the geckos, but some other lizards 
have ears that are as sensitive as some geckos. 
Werner, Y.L. 1965 
Ptyodactylus sp. 
The call of Ptyodactylus consists of a series of 
barks. Some subspecies have differing calls. 
sive face-off posture, signaling that attack is 
imminent. But, it does not appear to have 
a direct analog in visual display behavior. 
Milton (1974) has pointed out that Anolis 
grahami produces sounds during intraspe- 
cific conflicts. These sounds are contextually 
and structurally similar to churr calls of 
H. frenatus. 
The multiple chirp call appears to be simi- 
lar in function to much of the display be- 
havior of the two iguanid species. As in 
most visual displays, it is emitted predomi- 
nantly by males in situations associated with 
the visual assertion and challenge displays of 
iguanids. 
Hemidactylus frenatus and other noc- 
turnal geckos have not been shown to pos- 
sess anything comparable to the courtship 
needs of iguanid lizards. Diurnal geckos, 
such as Phelsuma, however, perform head 
movements when courting a female at close 
range (Kastle, 1964). In the diurnal species, 
the visual display seems to have the effect 
of keeping the female from running away. 
In nocturnal lizards, on the contrary, the 
male can approach closely without being 
seen, rush the female, and mate with her. 
In H. frenatus no close-range courtship be- 
havior was seen. Males approached to within 
a few feet, then rushed the female, obtained 
a neck grip, and copulated. 
That acoustic and visual displays of 
lizards show analogies is not surprising. The 
two groups presumably had a common an- 
cestry, and they have similarities in their 
population ecology that is reflected in com- 
parable social systems in which similar 
messages are conveyed. 
Social messages can apparently be trans- 
mitted equally well by visual or acoustic sys- 
tems. Both systems allow a great diversity 
of messages, one providing variations in 
color, pattern and movement, the other, dif- 
ferences in frequency, intensity, and pat- 
tern. The systems have the capacity for pro- 
ducing stereotyped, reproducible messages. 
Both channels can function well as direc- 
tional systems and both afford rapid trans- 
mission over considerable distances. The 
major difference is that the visual system is 
