There are multiple hypotheses for the spectacular plant diversity found in deserts. We explore how different factors, including the roles of ecological opportunity and selection, promote diversification and disparification in Using a nearly complete species‐level phylogeny based on double‐digest restriction‐aided sequencing along with a broad set of phenotypic traits, we estimate divergence times and diversification rates, identify instances of hybridization, quantify trait disparity and assess phenotypic divergence across environmental gradients. We show that
Natural selection is an important driver of genetic and phenotypic differentiation between species. For species in which potential gene flow is high but realized gene flow is low, adaptation via natural selection may be a particularly important force maintaining species. For a recent radiation of New World desert shrubs (
- NSF-PAR ID:
- 10206066
- Publisher / Repository:
- Proceedings of the National Academy of Sciences
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 117
- Issue:
- 52
- ISSN:
- 0027-8424
- Page Range / eLocation ID:
- p. 33373-33383
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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