Genetic Similarity of Island Populations of Tent Caterpillars during Successive Outbreaks

Resource type
Date created
2014-05-23
Authors/Contributors
Abstract
Cyclic or fluctuating populations experience regular periods of low population density. Genetic bottlenecks during these periods could give rise to temporal or spatial genetic differentiation of populations. High levels of movement among increasing populations, however, could ameliorate any differences and could also synchronize the dynamics of geographically separated populations. We use microsatellite markers to investigate the genetic differentiation of four island and one mainland population of western tent caterpillars, Malacosoma californicum pluviale, in two periods of peak or pre-peak density separated by 8 years. Populations showed high levels of genetic variation and little genetic differentiation either temporally between peaks or spatially among sites. Mitochondrial haplotypes were also shared between one island population and one mainland population in the two years studied. An isolation-by-distance analysis showed the FST values of the two geographically closest populations to have the highest level of differentiation in both years. We conclude that high levels of dispersal among populations maintain both synchrony of population dynamics and override potential genetic differentiation that might occur during population troughs. As far we are aware, this is the first time that genetic similarity between temporally separated population outbreaks in insects has been investigated. A review of genetic data for both vertebrate and invertebrate species of cyclic animals shows that a lack of spatial genetic differentiation is typical, and may result from high levels of dispersal associated with fluctuating dynamics.
Document
Published as
Franklin MT, Myers JH, Cory JS (2014) Genetic Similarity of Island Populations of Tent Caterpillars during Successive Outbreaks. PLoS ONE 9(5): e96679. doi:10.1371/journal.pone.0096679
Publication title
PLoS ONE
Document title
Genetic Similarity of Island Populations of Tent Caterpillars during Successive Outbreaks
Date
2014
Volume
9
Issue
5
Publisher DOI
10.1371/journal.pone.0096679
Copyright statement
Copyright is held by the author(s).
Scholarly level
Peer reviewed?
Yes
Language
Member of collection
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2.pdf 4.63 MB