Population Structures

In contrast to many animal population models individuals in a population are not equal. Some of these individual differences even have a genetic background and one wonders how these individual differences can persist in natural populations. Are they a mere byproduct of the genetic structure of individuals or should they be seen as subtle adaptations to coexist with other members of the species? With these fascinating questions we enter the domain of the study of frequency dependent success, when the success of a certain type of individual depends on the number and type of the competitors.

To get an answer on these questions we study personalities in Great tits in the wild (in close collaboration with NIOO in Heteren and the Behaviour group in Groningen) and offspring sex ratio in the great tit (see also dispersal ecology). The personality of free-living birds and their subsequent survival and reproduction is measured. Personalities are heritable, can be selected on and have strong and complex fitness effects in the natural situation, differing in direction between years and sexes. The next step is an experimental approach to determine the frequency dependent factor in this system. To that end we team up with the large scale experiment on sex ratio manipulation on a plot scale currently performed in the great tit population of the Lauwersmeer specifically aimed at measuring frequency dependent dispersal decisions caused by sex ratio skews.

Projects related to this theme

Population regulation and persistence of small isolated populations (PhD Lyanne Brouwer)