Experimental evolution:

The majority of the research carried out in the Snook lab uses laboratory reared populations of a species of fruit fly known as Drosophila pseudoobscura. Most importantly, these particular populations have been evolving for over 100 generations under three different experimentally imposed sexual selection regimes. This enables us to test the effects of varying levels of sexual selection, ranging from enforced monogamy to elevated promiscuity, on a huge range of characteristics. Figure 1 (below), explains the selection line regimes.

 Figure 1. The first experimental treatment is a monogamous line (M) in which one male is housed with one female and so sexual selection is not present. Second we have the control line (C) in which one female is housed with three males and so intermediate levels of sexual selection are present. And finally, Elevated promiscuity (E) in which one female is housed with six males giving high levels of sexual selection. Each of these three treatments has been replicated four times giving a total of twelve populations.