Linked Life Data

18540948

Source:http://linkedlifedata.com/resource/pubmed/id/18540948

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
2008-9-24
pubmed:abstractText
Pronounced phenotypic shifts in island populations are typically attributed to natural selection, but reconstructing heterogeneity in long-term selective regimes remains a challenge. We examined a scenario of divergence proposed for species colonizing a new environment, involving directional selection with a rapid shift to a new optimum and subsequent stabilization. We provide some of the first empirical evidence for this model of evolution using morphological data from three timescales in an island bird, Zosterops lateralis chlorocephalus. In less than four millennia since separation from its mainland counterpart, a substantial increase in body size has occurred and was probably achieved in fewer than 500 generations after colonization. Over four recent decades, morphological traits have fluctuated in size but showed no significant directional trends, suggesting maintenance of a relatively stable phenotype. Finally, estimates of contemporary selection gradients indicated generally weak directional selection. These results provide a rare description of heterogeneity in long-term natural regimes, and caution that observations of current selection may be of limited value in inferring mechanisms of past adaptation due to a lack of constancy even over short time-frames.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0014-3820
pubmed:author
pubmed:issnType
Print
pubmed:volume
62
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2393-410
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
4000 years of phenotypic change in an island bird: heterogeneity of selection over three microevolutionary timescales.
pubmed:affiliation
Division of Biology, Imperial College London, Silwood Park, Ascot, Berkshire SL5 7PY, United Kingdom. sonya.clegg@imperial.ac.uk
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't