Conditional Manipulation of Sex Ratios by Ant Workers: A Test of Kin Selection Theory
Variable queen mating frequencies provide a unique opportunity to study the resolution of worker-queen conflict over sex ratio in social Hymenoptera, because the conflict is maximal in colonies headed by a singly mated queen and is weak or nonexistent in colonies headed by a multiply mated queen. In the wood ant Formica exsecta, workers in colonies with a singly mated queen, but not those in colonies with a multiply mated queen, altered the sex ratio of queen-laid eggs by eliminating males to preferentially raise queens. By this conditional response to queen mating frequency, workers enhance their inclusive fitness.
Sundstrom
L
L. Sundstrom, University of Lausanne, IZEA, Batiment de Biologie, CH-1015 Lausanne, Switzerland; University of Bern, Ethologische Station Hasli, CH-3032 Hinterkappelen, Switzerland; and University of Aarhus, Department of Genetics and Ecology, DK-8000 Aarhus C, Denmark. M. Chapuisat, University of Lausanne, IZEA, Batiment de Biologie, CH-1015 Lausanne, Switzerland, and Museum of Zoology, Palais de Rumine, Case Postale 448, CH-1000 Lausanne 17, Switzerland. L. Keller, University of Lausanne, IZEA, Batiment de Biologie, CH-1015 Lausanne, Switzerland, and University of Bern, Ethologische Station Hasli, CH-3032 Hinterkappelen, Switzerland.
Chapuisat
M
Keller
L