Evol Ecol Res 8: 63-73 (2006)     Full PDF if your library subscribes.

Population regulation by dispersal under selection pressure for and against dispersal: an experimental test with beetles, Tribolium confusum

Adam Łomnicki*

Institute of Environmental Sciences, Jagiellonian University, ul. Gronostajowa 7, 30-387 Kraków, Poland

e-mail: lomnicki@eko.uj.edu.pl


Hypothesis: Dispersal outside a local population maintains population density below the possible maximum, but within a single local population selection acts against dispersal and consequently against such maintenance. Individuals that disperse exhibit lower fitness that is correlated with their smaller body size.

Organism: Laboratory populations of Tribolium confusum beetles.

Methods: Four confined populations with no dispersal, four with the progeny of dispersing individuals removed and four with the progeny of non-dispersing individuals removed were maintained and monitored for seven generations.

Results: Confined populations were larger than those from which dispersal was allowed. From generation three onwards, dispersal rates were significantly lower in the population in which progeny of dispersing beetles were removed than in the population in which progeny of non-dispersing beetles were removed. The differences in dispersal rates mentioned above affected population density in the native populations but not in the places to which beetles emigrated. The removal of the progeny of dispersing individuals does not eradicate dispersal altogether. Average body weights of dispersing beetles are not lower than of those of non-dispersing beetles.

Keywords: metapopulation, migration, population density, Tribolium laboratory populations.

IF you are connected using the IP of a subscribing institution (library, laboratory, etc.)
or through its VPN.


        © 2006 Adam Łomnicki. All EER articles are copyrighted by their authors. All authors endorse, permit and license Evolutionary Ecology Ltd. to grant its subscribing institutions/libraries the copying privileges specified below without additional consideration or payment to them or to Evolutionary Ecology, Ltd. These endorsements, in writing, are on file in the office of Evolutionary Ecology, Ltd. Consult authors for permission to use any portion of their work in derivative works, compilations or to distribute their work in any commercial manner.

       Subscribing institutions/libraries may grant individuals the privilege of making a single copy of an EER article for non-commercial educational or non-commercial research purposes. Subscribing institutions/libraries may also use articles for non-commercial educational purposes by making any number of copies for course packs or course reserve collections. Subscribing institutions/libraries may also loan single copies of articles to non-commercial libraries for educational purposes.

       All copies of abstracts and articles must preserve their copyright notice without modification.