Affiliations 

  • 1 Department of Ecology and Evolutionary Biology and Biodiversity Institute, The University of Kansas, Lawrence, KS, USA
  • 2 Department of Biology, University of Florida, Gainesville, FL, USA
  • 3 Faculty of Natural Science and Sustainability, University College Sabah Foundation, Kota Kinabalu, Sabah, Malaysia
  • 4 Sabah Parks, Kota Kinabalu, Sabah, Malaysia
  • 5 Museum of Natural Science and Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, USA
PeerJ, 2017;5:e3335.
PMID: 28533979 DOI: 10.7717/peerj.3335

Abstract

Topographically complex regions often contain the close juxtaposition of closely related species along elevational gradients. The evolutionary causes of these elevational replacements, and thus the origin and maintenance of a large portion of species diversity along elevational gradients, are usually unclear because ecological differentiation along a gradient or secondary contact following allopatric diversification can produce the same pattern. We used reduced representation genomic sequencing to assess genetic relationships and gene flow between three parapatric pairs of closely related songbird taxa (Arachnothera spiderhunters, Chloropsis leafbirds, and Enicurus forktails) along an elevational gradient in Borneo. Each taxon pair presents a different elevational range distribution across the island, yet results were uniform: little or no gene flow was detected in any pairwise comparisons. These results are congruent with an allopatric "species-pump" model for generation of species diversity and elevational parapatry of congeners on Borneo, rather than in situ generation of species by "ecological speciation" along an elevational gradient.

* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.