The Social Behavior of Some Desert Lizards

Brattstrom, Bayard H.

Horned Lizard Ranch

P.O. Box 166

Wikieup, AZ 85360

bayard@hughes.net

Studies on the social behavior of lizards have shown them capable of a variety of sociality that exceed that founds in some birds and mammals. Much of lizard behavior is simple and genetic (displays, courtship), while others are learned. There is density and resource related determinants of social behavior (food, hiding, egg-laying places). With an increase in population numbers (an increase in density) aggressive interactions increase and behavior may switch from territory to hierarchy. Most lizards in most situations know their social status by virtue of size, color, odors, sounds, or behavior of dominants. Subordinates respond by behaviors or postures (escape, submission, waves) to indicate submission, thereby avoiding energetically expensive or risky social behavior. While elaborate male-male displays are known for quite a few species, complete behavioral inventories (ethograms) are known for only a few. Here, I report on postures, positions, and ethograms for nine species of lizards of the southwestern United States.