162 
Crews 
processus 
entoglossus 
first part of 
ant. horn 
second part 
of ant. horn 
processus 
retrobasalis 
10 mm - 
Figure 10. Hyoid apparatus of the male lizard, Anolis carolinensis. 
Table 2 Response of sexually receptive 
female Anolis carolinensis to the courtship 
of hyoidectomized and blue-dewlapped 
males, respectively. 
Test Male 
Female Sexual Receptivity 
Receptive 
Nonreceptive 
Hyoidectomized 
Male 
2 
10 
Blue-dewlapped 
Male 
9 
3 
p<0.01, phi coefficient 
tomized males but are receptive to the court- 
ship of blue-dewlapped males (Table 2). 
These experiments suggest, therefore, that 
the critical factor in both courtship facilita- 
tion of environmentally induced OR and in 
mate selection in A. carolinensis is the ability 
of the male to extend the dewlap, thus chang- 
ing his body shape, and not the color of his 
dewlap. 
Certain limitations, however, must be 
placed on this interpretation. For example, 
we do not know if it is important for the 
male to change the body profile in a species- 
typical manner, e.g., in conjunction with the 
bobbing movement. Nor do we know if the 
lack of dewlap color per se is important for 
these physiological and social effects. 
Adaptive significance of courtship 
facilitation and male-male aggression 
inhibition of environmentally induced 
ovarian recrudescence 
Let me summarize this series of experi- 
ments on the factors controlling seasonal 
ovarian recrudescence in A. carolinensis by 
way of hypothesizing about the possible 
adaptive function of courtship facilitation 
and male-male aggression inhibition of en- 
