Quantitative genetic effects of bottlenecks: experimental evidence from a wild plant species, Nigella degenii
2010 (English)In: Journal of Heredity, ISSN 0022-1503, E-ISSN 1465-7333, Vol. 101, no 3, 298-307 p.Article in journal (Refereed) Published
Understanding the genetic consequences of changes in population size is fundamental in a variety of contexts, such as adaptation and conservation biology. In the study presented here, we have performed a replicated experiment with the plant Nigella degenii to explore the quantitative genetic effects of a single-founder bottleneck. In agreement with adetive theory, the bottleneck reduced the mean (co)variance within lines and caused stochastic, line-specific changes in the genetic (co)variance structure. However, a significant portion of the (co)variance structure was conserved, and 2 characters—leaf and flower (sepal) size—turned out to be positively correlated in all data sets, indicating a potential for correlated evolution in these characters, even after a severe bottleneck. The hierarchical partitioning of genetic variance for flower size was in good agreement with predictions from additive theory, whereas the remaining characters showed an excess of within-line variance and a deficiency of among-line variance. The latter discrepancies were most likely a result of selection, given the small proportion of lines (23%) that remained viable until the end of the experiment. Our results suggest that bottlenecked populations of N. degenii generally have a lower adaptive potential than the ancentral population but also highlight the idiosyncratic nature of bottleneck effects.
Place, publisher, year, edition, pages
2010. Vol. 101, no 3, 298-307 p.
bottleneck, evolutionary constraint, G matrix, genetic drift, Nigella degenii
Research subject Genetics
IdentifiersURN: urn:nbn:se:su:diva-32485DOI: 10.1093/jhered/esp108OAI: oai:DiVA.org:su-32485DiVA: diva2:280720