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Title: Implications of headwater contact zones for the riverine barrier hypothesis: a case study of the Blue-capped Manakin ( Lepidothrix coronata )
Abstract

Rivers frequently delimit the geographic ranges of species in the Amazon Basin. These rivers also define the boundaries between genetic clusters within many species, yet river boundaries have been documented to break down in headwater regions where rivers are narrower. To explore the evolutionary implications of headwater contact zones in Amazonia, we examined genetic variation in the Blue-capped Manakin (Lepidothrix coronata), a species previously shown to contain several genetically and phenotypically distinct populations across the western Amazon Basin. We collected restriction site-associated DNA sequence data (RADcap) for 706 individuals and found that spatial patterns of genetic structure indicate several rivers, particularly the Amazon and Ucayali, are dispersal barriers for L. coronata. We also found evidence that genetic connectivity is elevated across several headwater regions, highlighting the importance of headwater gene flow for models of Amazonian diversification. The headwater region of the Ucayali River provided a notable exception to findings of headwater gene flow by harboring non-admixed populations of L. coronata on opposite sides of a < 1-km-wide river channel with a known dynamic history, suggesting that additional prezygotic barriers may be limiting gene flow in this region.

 
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NSF-PAR ID:
10484282
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Oxford University Press
Date Published:
Journal Name:
Evolution
Volume:
78
Issue:
1
ISSN:
0014-3820
Format(s):
Medium: X Size: p. 53-68
Size(s):
["p. 53-68"]
Sponsoring Org:
National Science Foundation
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