Lizard Ethology 
209 
Such preliminary work contributes to one’s 
confidence in the “normality” of behavior 
when a laboratory habitat is modified to 
emphasize behavioral patterns or to facilitate 
observations of behavioral patterns of special 
interest. 
Observations 
The techniques employed in making be- 
havioral observations must be adapted for 
each species of lizard in their experimental 
habitats. Anolis carolinensis seems less sub- 
ject than many other lizards to the observer 
effect, and it is possible to record their ac- 
tivity while seated a few meters away in a 
darkened room. Blue spiny and rainbow liz- 
ards are another matter. There is no one 
ideal way to observe them, but a balanced 
use of direct observations through a blind 
fitted with a one-way window and closed cir- 
cuit television is effective. 
The video monitoring system I employ 
consists of two monitors attached to a zoom 
lens capable of very close focus (e.g., Dage 
model RGS-50) and a third monitor attached 
to a wide angle camera so that an animal 
can be quickly located and peripheral 
activity followed (Fig. 4). The use of a time- 
lapse videotape recorder (e.g., GYYR model 
VTL 300) also allows relatively straight- 
forward analysis with resolution of up to 
60 frames per second in replay. The tongue 
touching of the substrate commonly asso- 
ciated with the Agama’s display may be re- 
vealed clearly in only one frame. By record- 
ing in the time-lapse mode, up to 99 hours 
may be compressed onto a 1-hour tape. 
The Esterline-Angus pen-writing event 
recorder controlled by on-off-momentary 
switches continues to provide a reliable 
means for the recording of continuous states 
(e.g., postures, color, territorial sites) as well 
as momentary events (e.g., motor acts). 
For extended observation of large numbers 
of delineated behavioral units, Dr. Richard 
Radna and I are developing a system that 
converts any conventional communications 
terminal into an event recorder by the use of 
RECORDING 
AND COPY 
MONITOR 
Figure 4. Separate closed-circuit television moni- 
tors are connected to (1) a zoom camera capable 
of extreme closeups and (2) a wide-angle camera 
so that peripheral action can be followed or an 
animal quickly located. The picture on either moni- 
tor can be recorded and events of interest can be 
quickly copied onto an adjacent recorder. 
a system of FORTRAN programs called 
CABER (programs and user’s guide avail- 
able). CABER permits us to enter any 
two-digit alpha-numeric code as one would 
type. The internal clock of an IBM 370 is 
accessed, and the time, to whatever precision 
desired (up to one-hundredths of a second) 
is entered whenever the return key is hit 
(Fig. 6). 
CONSTRAINTS ON BEHAVIOR 
Microclimate 
The quality and quantity of light are not 
only of importance for thermoregulation in 
ectothermic lizards, but influence behavior in 
other ways. Photoperiod length has been 
associated with gonadal regulation (Fox and 
Dessauer, 1958), appetite and growth (Fox 
and Dessauer, 1957). Species differences in 
response are apparent (Mayhew, 1964), and 
the response to photoperiod may be substan- 
tially altered by the ambient temperature 
(Licht, 1973), humidity (Crews et al., 1974), 
and possibly population density. In my study 
