Details

Autor(en) / Beteiligte

• Fox, Charles W.
• Reed, David H.

Titel

INBREEDING DEPRESSION INCREASES WITH ENVIRONMENTAL STRESS: AN EXPERIMENTAL STUDY AND META-ANALYSIS

Ist Teil von

• Evolution, 2011-01, Vol.65 (1), p.246-258

Ort / Verlag

Malden, USA: Blackwell Publishing Inc

Erscheinungsjahr

2011

Quelle

MEDLINE

Beschreibungen/Notizen

• Inbreeding–environment interactions occur when inbreeding leads to differential fitness loss in different environments. Inbred individuals are often more sensitive to environment stress than are outbred individuals, presumably because stress increases the expression of deleterious recessive alleles or cellular safeguards against stress are pushed beyond the organism's physiological limits. We examined inbreeding–environment interactions, along two environmental axes (temperature and rearing host) that differ in the amount of developmental stress they impose, in the seed-feeding beetle Collosobruchus maculatus. We found that inbreeding depression (inbreeding load, L) increased with the stressfulness of the environment, with the magnitude of stress explaining as much as 66% of the variation in inbreeding depression. This relationship between L and developmental stress was not explainable by an increase in phenotypic variation in more stressful environments. To examine the generality of this experimental result, we conducted a meta-analysis of the available data from published studies looking at stress and inbreeding depression. The meta-analysis confirmed that the effect of environment on inbreeding depression scale linearly with the magnitude of stress; a population suffers one additional lethal equivalent, on average, for each 30% reduction in fitness induced by the stressful environment. Studies using less-stressful environments may lack statistical power to detect the small changes in inbreeding depression. That the magnitude of inbreeding depression scales with the magnitude of the stress applied has numerous repercussions for evolutionary and conservation genetics and may invigorate research aimed at finding the causal mechanism involved in such a relationship.