Rivers, not refugia, drove diversification in arboreal, sub-Saharan African snakes

© 2021 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd..

The relative roles of rivers versus refugia in shaping the high levels of species diversity in tropical rainforests have been widely debated for decades. Only recently has it become possible to take an integrative approach to test predictions derived from these hypotheses using genomic sequencing and paleo-species distribution modeling. Herein, we tested the predictions of the classic river, refuge, and river-refuge hypotheses on diversification in the arboreal sub-Saharan African snake genus Toxicodryas. We used dated phylogeographic inferences, population clustering analyses, demographic model selection, and paleo-distribution modeling to conduct a phylogenomic and historical demographic analysis of this genus. Our results revealed significant population genetic structure within both Toxicodryas species, corresponding geographically to river barriers and divergence times from the mid-Miocene to Pliocene. Our demographic analyses supported the interpretation that rivers are indications of strong barriers to gene flow among populations since their divergence. Additionally, we found no support for a major contraction of suitable habitat during the last glacial maximum, allowing us to reject both the refuge and river-refuge hypotheses in favor of the river-barrier hypothesis. Based on conservative interpretations of our species delimitation analyses with the Sanger and ddRAD data sets, two new cryptic species are identified from east-central Africa. This study highlights the complexity of diversification dynamics in the African tropics and the advantages of integrative approaches to studying speciation in tropical regions.

Medienart:

E-Artikel

Erscheinungsjahr:

2021

Erschienen:

2021

Enthalten in:

Zur Gesamtaufnahme - volume:11

Enthalten in:

Ecology and evolution - 11(2021), 11 vom: 28. Juni, Seite 6133-6152

Sprache:

Englisch

Beteiligte Personen:

Allen, Kaitlin E [VerfasserIn]
Greenbaum, Eli [VerfasserIn]
Hime, Paul M [VerfasserIn]
Tapondjou N, Walter P [VerfasserIn]
Sterkhova, Viktoria V [VerfasserIn]
Kusamba, Chifundera [VerfasserIn]
Rödel, Mark-Oliver [VerfasserIn]
Penner, Johannes [VerfasserIn]
Peterson, A Townsend [VerfasserIn]
Brown, Rafe M [VerfasserIn]

Links:

Volltext

Themen:

Historical demography
Journal Article
Machine learning
Paleo‐distributions
Phylogenomics
Toxicodryas

Anmerkungen:

Date Revised 19.06.2021

published: Electronic-eCollection

Citation Status PubMed-not-MEDLINE

doi:

10.1002/ece3.7429

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM32688744X