160 
Crews 
strongly facilitates the stimulatory effects of 
the out-of-season environmental regime. This 
finding also suggests that (1) in A. caro- 
linensis, male courtship insures normal 
gonadotropin secretion, (2) the absence of 
male courtship results in subnormal gonado- 
tropin secretion, as indicated by the laying 
of unshelled eggs, and (3) the presence of 
male-male aggression inhibits or greatly re- 
duces environmentally induced gondotropin 
secretion. 
Further experiments in which winter- 
dormant females were exposed to either high 
or low frequency courtship males indicated 
that gonadotropin secretion is graded in 
accordance with the amount of male court- 
ship to which the female is exposed (Crews, 
1974a). Only those females exposed to the 
high levels of male courtship exhibited the 
typical pattern of courtship facilitation of 
OR demonstrated in the previous experi- 
ments. Females exposed to low levels of male 
courtship exhibited a significantly less rapid 
rate of ovarian activity that was not differ- 
ent from that of females housed with cas- 
trated males that did not court at all. 
As might be expected on the basis of pre- 
vious experiments with mammals and birds 
(Bermant and Davidson, 1974), male court- 
ship behavior and, in turn, courtship facili- 
tation of environmentally induced OR in A. 
carolinensis are dependent upon testicular 
secretions. In another experiment, I demon- 
strated that castration abolished male court- 
ship behavior and androgen replacement 
therapy reinstated male courtship activity 
to preexisting levels (Crews, 19746). In 
addition, ovarian growth was more rapid 
among those females exposed to intact males 
and castrated males with androgen implants 
than among females exposed to castrated 
males with or without cholesterol implants 
(Fig. 9). 
Stimulus factors in courtship facilitation 
of environmentally induced ovarian 
recrudescence 
Ritualized behavior patterns, such as male 
courtship displays, are integrated sequences 
of complex motor patterns or acts. Is it 
necessary for the female to perceive the 
entire display of the male in order for the 
display to have its effect? What component (s) 
of the male’s courtship display is responsible 
for the facilitation of environmentally in- 
duced OR? 
By dissecting the stimulus configuration 
presented by the courting male to the female 
into its parts, it should be possible to examine 
both their individual long-term physiological 
or “priming” effects — that is, their relative 
effectiveness in facilitating environmentally 
induced OR — as well as their short-term be- 
havioral or “releasing” effects — that is, their 
role in mate selection. 
Taking this approach, I arbitrarily divided 
the male courtship display of A. carolinensis 
into the following components: the up-and- 
down bobbing movement, dewlap extension, 
and dewlap color. 
Dewlapping in anoles is accomplished by 
the extension of a thin flexible part of the 
hyoid apparatus called the processus retro- 
basilis (Fig. 10). By surgically removing 
this cartilage, males were obtained which 
were able to perform all of the behavior pat- 
terns associated with courtship except the 
physical extension of the dewlap. To analyze 
the importance of the color of the dewlap, 
dewlaps of another group of males were in- 
jected with India ink; this produced males 
with blue dewlaps as compared with normal, 
red-dewlapped males (Crews, 1975a). 
In the first experiment with these different- 
stimulus males, winter-dormant females were 
housed with either (1) a castrated male 
which was never observed to court, (2) an 
intact red-dewlapped male, which courted 
normally, (3) a hyoidectomized male which 
performed the bobbing and strutting advance 
characteristic of male courtship but, because 
his hyoid cartilage had been removed, could 
not extend the dewlap, or (4) a blue-dew- 
lapped male which performed all the be- 
havior patterns associated with male court- 
ship but whose dewlap was the “wrong” 
color. 
