Accelerating climate change and habitat loss make it imperative that plans to conserve biodiversity consider species' ability to adapt to changing environments. However, in biomes where biodiversity is highest, the evolutionary mechanisms responsible for generating adaptative variation and, ultimately, new species are frequently poorly understood. African rainforests represent one such biome, as decadal debates continue concerning the mechanisms generating African rainforest biodiversity. These debates hinge on the relative importance of geographic isolation versus divergent natural selection across environmental gradients. Hindering progress is a lack of robust tests of these competing hypotheses. Because African rainforests are severely at‐risk due to climate change and other anthropogenic activities, addressing this long‐standing debate is critical for making informed conservation decisions. We use demographic inference and allele frequency‐environment relationships to investigate mechanisms of diversification in an African rainforest skink,
Closely related species with parapatric elevational ranges are ubiquitous in tropical mountains worldwide. The gradient speciation hypothesis proposes that these series are the result of in situ ecological speciation driven by divergent selection across elevation. Direct tests of this scenario have been hampered by the difficulty inferring the geographic arrangement of populations at the time of divergence. In cichlids, sticklebacks and
- PAR ID:
- 10455905
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Journal of Evolutionary Biology
- Volume:
- 33
- Issue:
- 11
- ISSN:
- 1010-061X
- Format(s):
- Medium: X Size: p. 1643-1652
- Size(s):
- p. 1643-1652
- Sponsoring Org:
- National Science Foundation
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