Correlates of Tail Losses in Twelve Species of Liolaemus Lizards

The relative frequencies of naturally occurring tail losses in twelve species of central Chile Liolaemus are reported. It was found that percentages vary between 23.8% and 77.2%. In an attempt to explain these differences, percent tail losses was correlated with an estimate of time exposed to predators (size of the lizards), with an estimate of intraspecific susceptibility to predators (sexual dimorphism), and with percent occupation of conspicuous perches. Partial correlation analysis exhibited statistical significance only with the latter variable, thus suggesting that visibility to predators could be causally related to tail losses. A last cautionary word is offered, indicating that frequency of tail losses is not a measure of predation pressure, but of successful escapes after at least one close encounter with a predator.