Sexual selection – population density

Impact of population density on sexual selection in the red flour beetle

Supervisor: Lennart Winkler (BIO Room 257) & Dr. Tim Janicke


Project start: From summer 2021

Background: Sexual selection is considered a potent evolutionary force explaining the bewildering diversity of differences between males and females. Recent work suggests that the strength of sexual selection can vary substantially among populations but we are only beginning to understand this inter-specific variation (but see McLain 1982, Conner 1989 & Levitan 2004). One of the most prominent demographic factors showing often drastic inter-specific differences is density. However, we know surprisingly little about the effect of density on the strength and form of sexual selection. In this project we will quantify so-called Bateman metrics (Bateman 1948) to explore the causal relationship between density and sexual selection using the red flour beetle as a model system. Main tasks of this project include animal breeding, behavioural observations/recordings and statistical modelling. 


Bateman A. J. 1948. Intra-Sexual Selection in Drosophila. Heredity (Edinb). 2:349–368. 

Levitan DR. 2004. Density-dependent sexual selection in external fertilizers: Variances in male and female fertilization success along the continuum from sperm limitation to sexual conflict in the sea urchin Strongylocentrotus franciscanus. Am Nat. 164(3):298–309.

McLain DK. 1982. Density dependent sexual selection and positive phenotypic assortative mating in natural populations of the soldier beetle, Chauliognathus pennsylvanicus. Evolution (N Y). 36(6):1227–1235.