Expansion and intensification of human land use represents the major cause of habitat fragmentation. Such fragmentation can have dramatic consequences on species richness and trophic interactions within food webs.
Using a genetic algorithm*, we quantified how habitat fragmentation and environmental variability affect the optimal reproductive strategies of parasitic wasps foraging for hosts. The model is based on the existence of a negative trade-off between survival and reproduction resulting from competitive allocation of resources to either somatic maintenance or egg production. We also asked to what degree plasticity along this trade-off would be optimal, when plasticity* is costly. We found that habitat fragmentation can indeed have strong effects on the reproductive strategies adopted by parasitoids. With increasing habitat fragmentation animals should invest in greater longevity with lower fecundity.
*Genetic algorithm: Computational analysis based on biological process (as natural selection).
*Phenotypic plasticity: Range of phenotypes linked to one genotype.
- Wajnberg E., P. Coquillard, L.E.M. Vet & T. Hoffmeister (2012a). Optimal resource allocation to survival and reproduction in parasitic wasps foraging in fragmented habitats.PLoS ONE, 7(6), e38227.