| FLOYD HAYES |
| Hayes, F. E., K. R. Beaman, W. K. Hayes, and L. E. Harris, Jr. 1988. Defensive behavior in the Gal�pagos Tortoise (Geochelone elephantopus), with comments on the evolution of insular gigantism. Herpetologica 44:11-17. Abstract.--Defensive behavior of the Galapagos Tortoise (Geochelone elephantopus) was studied at Volcan Alcedo, Isabela Island, Galapagos Islands, Ecuador. The tortoises exhibited a variety of distinctive behavioral responses during and following the approach of an investigator. Withdrawal distances and subsequent protrusion latencies were not appreciably affected by body size or age. Because Galapagos tortoises have retained a defensive behavioral repertoire similar to that described in turtles from continental areas, we reject the hypothesis that the loss, reduction, or modification of antipredator strategies in island tortoises contributed to the development of gigantism. Rather, insular gigantism probably evolved from factors related to ecological conditions. Key words.--Reptilia, Chelonia, Testudinae, Geochelone elephantopus, behavior, defense, insular gigantism |
| ABSTRACTS |