Antarctic Collembolans Use Chemical Signals to Promote Aggregation and Egg Laying

Terrestrial arthropods that reside in Antarctica are exposed to considerable periods of environmental stress, thus factors that promote identification of favorable microhabitats are extremely important. In this study, we report the presence of chemical cues that induce oviposition and aggregation in two species of Antarctic collembolans, Cryptopygus antarcticus and Friesea grisea. Responses of the Collembola were enhanced by low temperatures but were not altered by humidity. One of the major physiological benefits derived from an aggregation was a substantial reduction in water loss rates. Although F. grisea and C. antarcticus were commonly found in cross-species aggregations, we found no evidence to suggest cross-species attraction. When individuals were exposed to areas previously occupied by groups of Collembola, more eggs were laid. Thus, chemicals released by the collembolans appear to induce both aggregation and oviposition in these Antarctic species.