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Dissection and Flat-mounting of the Threespine Stickleback Branchial Skeleton
Published on: May 7, 2016
Strength in numbers: High phenotypic variance in early Cambrian trilobites and its evolutionary implications
1Department of Earth Sciences, University of California, Riverside, CA 92521, USA. nigel.hughes@ucr.edu
Abstract:
Analysis of the degree of intraspecific morphological polymorphism during the evolutionary history of trilobites using an informatic approach(1) provides striking evidence of a long-suspected but previously unsubstantiated pattern: degrees of polymorphism are markedly higher in phylogenetically basal, stratigraphically early species. This unequivocal pattern prompts further exploration of the relationship between microevolutionary variance and macroevolutionary history. It demonstrates that the 'traditional' fossil record of skeletonized organisms can provide unique insight into questions of major evolutionary interest.
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