THOMAS JENSSEN (Department of Biology, Virginia Polytechnic Institute 
and State University, Blacksburg, Virginia 24061) has, as always, his 
major attention fixed on anole displays. He has done some of the work in 
Panama at the anole facility and some at VPI. 
A study of the Bogota Phenacosaurus brought back by E. E. Williams, 
Jane Peterson, Kenneth Miyata and Richard Salvato provides him with a 
display pattern somewhat different from that described by Kástle but 
nevertheless a typical iguanid display repertoire - very strong stereotypy 
with a limited assortment of "assertion," "challenge" and courtship displays. 
The challenge display is an elaboration of the assertion display coupled 
with throat fan extension and exaggerated amplitude of bobs. 
Anolis nebulosus he finds more complex with some modifying movements 
that exaggerate the assertion and challenge displays. There is also 
dewlap pulsing which is not found in non-anole species. 
Anolis limifrons, which he has worked on along with his student Ed 
Hover he finds still more complex. He promises that it will be "by far 
the most thorough behavioral analysis of a lizard to date." Basically 
there are five agonistic display types and within each a hierarchy of 
modifiers that indicate grades of motivational intensity. These display 
types generally appear sequentially. The picture is further complicated 
by the fact that males usually display in volleys of two to four displays 
at a time, The first display of a volley is either of a higher motivational 
state than the following types or has the most modifiers of all the displays 
if all the displays of a volley are of the same display type. 
Anolis townsendi from Cocos Island in the Pacific falls into the 
limifrons mold, Four agonistic displays were found, but Jenssen suspects 
a fifth (occurring during very close male-male display exchanges) which was 
never recorded because the proper social context was not present during 
observations, A. townsendi, like A. limifrons, is thus a species with an 
expanded repertoire and with less stereotypy than is seen in A. nebulosus, 
l The variability in A. townsendi or A. limifrons is explainable, however, 
in contrast to the extreme variability of Jamaican A. opalinus, which is 
still an unsolved problem. Jenssen is still perplexed by the variability 
of just its assertion display. He tried analyzing low intensity assertion 
displays from five Jamaican localities. Five distinct patterns of the basic 
display were found, along with some regional differences in them. Any 
inc.vidual tended to perform one or two of these patterns but pattern usage 
by different individuals from the same locality differed considerably. 
There were a few lizards which had unique patterns as well as one or more 
of the usual five, To make sense of this, Jenssen will have to look at a 
lot more films, but his present impression is the displays have a genetic 
base but are not under strong selection pressure. His final word is: 
"It is this species that I hesitate to make any conclusione about except to 
say that I find little evidence for marked stereotypy.' 
