Document: MIC-3-52-51

The phenology of a neotropical ant assemblage--Testing for segregation in time.

KASPARI, M.* ¹, J.PICKERING ² and D.WINDSOR ³

University of Oklahoma, Norman OK 73019 USA ¹
Department of Zoology, University of Georgia, Athens GA USA ²
Smithsonian Tropical Research Institute, Balboa Panama ³

Abstract:
In ant colonies, alate flights reflect a colony's sexual reproduction and dispersal tactics. We studied the alate phenology of an ant assemblage on Barro Colorado, Panamaa seasonal rainforest. We combined results from two sampling methodstwo years of two malaise traps, and one year of two light traps. The 23,156 individuals were sorted to 292 species and morphospecies. Alate flights occurred every week of the year. Half of the most common species flew every month of the year. We analyzed the effects of weekly rainfall and lunar phase on flight activity. Quantile regression suggested that high weekly rainfall was necessary but not sufficient to produce alate flights in about 1/3 of the common species tested. Lunar phase, in contrast, did not predict alate activity. Common genera, tribes, and subfamilies often differed greatly in phenology, from uniform to highly pulsed reproduction concentrated in different seasons. However, congeneric species groups never significantly staggered flight times, based on results from the Variance Ratio test. To the contrary, most showed positive associations in flight activity over the year. The tropic's benign temperatures offer a yearlong flight window for its ant species that allows for a diversity of phenologies. However, it does not, it appears, promote speciation by temporal prezygotic isolating mechanisms at the monthly timescale.

Keywords: ant, tropics, phenology, prezygotic, rainfall, lunar

This abstract is being presented at: 5:00 PM in session:
Oral Session #53: Terrestrial Invertebrate Ecology.