Within- and between-population dispersal of sexuals of the ant

Seminar Thursday 22 June 2000, at Department of Population Ecology
Within- and between-population dispersal of sexuals of the ant
Formica exsecta
Cathy Liautard
PhD Student, University of Lausanne, Switzerland
One important issue in social behavior is to understand what factors may favor a shift from singlequeen to multiple-queen colonies in ants. When queen number increase, inside a colony, the mean
relatedness between the workers and the brood decrease, which decrease their inclusive fitness. It has
been suggested that low dispersal success of founder queen might be one important factor allowing the
evolution of multiple-queen colonies (polygyny) and the ensuing decreased relatedness among colony
members. Low dispersal success may stem from habitat saturation, patchy distribution of colonies,
and/or harsh climatic conditions. We are currently quantifying female dispersal in polygynous
populations of the ant Formica exsecta. This species lives in harsh ecological condition in the Swiss
Jura and has a very patchy distribution. To become reproductive queens have to either parasitized the
nest of other Formica species (Serviformica) or infiltrate an established colony of their own species.
We are using microsatellite and mtDNA RFLP markers to determine the genetic structure, breeding
system of nine populations in the Swiss Jura mountains. These data are also used to estimate the rate of
female dispersal within and between populations
Thursday d. 22 June, at 15:00 (precise)
Department of Population Ecology
Build. 12, Kollokvierum 1, 1st floor
Universitetsparken 15
2100 Kbh.Ø.