Evolutionary processes and its environmental correlates in the cranial morphology of western chipmunks (Tamias)

Author(s)

Assis, Ana Paula A. ; Rossoni, Daniela M. ; Patton, James L. ; Marroig, Gabriel

• Document type: Journal article
• Source: Evolution; v. 71, n. 3, p. 595-609, MAR 2017.
• Web of Science Citations: 5

Abstract

The importance of the environment in shaping phenotypic evolution lies at the core of evolutionary biology. Chipmunks of the genus Tamias (subgenus Neotamias) are part of a very recent radiation, occupying a wide range of environments with marked niche partitioning among species. One open question is if and how those differences in environments affected phenotypic evolution in this lineage. Herein we examine the relative importance of genetic drift versus natural selection in the origin of cranial diversity exhibited by clade members. We also explore the degree to which variation in potential selective agents (environmental variables) are correlated with the patterns of morphological variation presented. We found that genetic drift cannot explain morphological diversification in the group, thus supporting the potential role of natural selection as the predominant evolutionary force during Neotamias cranial diversification, although the strength of selection varied greatly among species. This morphological diversification, in turn, was correlated with environmental conditions, suggesting a possible causal relationship. These results underscore that extant Neotamias represent a radiation in which aspects of the environment might have acted as the selective force driving species' divergence. (AU)

• FAPESP's process: 14/12632-4 - Morphological evolution and cranial integration in Phyllostomidae
• Grantee: Daniela Munhoz Rossoni
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 11/14295-7 - Modularity and its evolutionary consequences
• Grantee: Gabriel Henrique Marroig Zambonato
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 12/00852-4 - Study of morphological changes and evolutionary processes in the mammal community of the Grinnell project
• Grantee: Ana Paula Aprígio Assis
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate