Idiosyncratic responses to climate-driven forest fragmentation and marine incursions in reed frogs from Central Africa and the Gulf of Guinea Islands

TY - JOUR

T1 - Idiosyncratic responses to climate-driven forest fragmentation and marine incursions in reed frogs from Central Africa and the Gulf of Guinea Islands

AU - Bell, Rayna C.

AU - Parra, Juan L.

AU - Badjedjea, Gabriel

AU - Barej, Michael F.

AU - Blackburn, David C.

AU - Burger, Marius

AU - Channing, Alan

AU - Dehling, Jonas Maximilian

AU - Greenbaum, Eli

AU - Gvoždík, Václav

AU - Kielgast, Jos

AU - Kusamba, Chifundera

AU - Lötters, Stefan

AU - McLaughlin, Patrick J.

AU - Nagy, Zoltán T.

AU - Rödel, Mark Oliver

AU - Portik, Daniel M.

AU - Stuart, Bryan L.

AU - VanDerWal, Jeremy

AU - Zassi-Boulou, Ange Ghislain

AU - Zamudio, Kelly R.

PY - 2017/10

Y1 - 2017/10

N2 - Organismal traits interact with environmental variation to mediate how species respond to shared landscapes. Thus, differences in traits related to dispersal ability or physiological tolerance may result in phylogeographic discordance among co-distributed taxa, even when they are responding to common barriers. We quantified climatic suitability and stability, and phylogeographic divergence within three reed frog species complexes across the Guineo-Congolian forests and Gulf of Guinea archipelago of Central Africa to investigate how they responded to a shared climatic and geological history. Our species-specific estimates of climatic suitability through time are consistent with temporal and spatial heterogeneity in diversification among the species complexes, indicating that differences in ecological breadth may partly explain these idiosyncratic patterns. Likewise, we demonstrated that fluctuating sea levels periodically exposed a land bridge connecting Bioko Island with the mainland Guineo-Congolian forest and that habitats across the exposed land bridge likely enabled dispersal in some species, but not in others. We did not find evidence that rivers are biogeographic barriers across any of the species complexes. Despite marked differences in the geographic extent of stable climates and temporal estimates of divergence among the species complexes, we recovered a shared pattern of intermittent climatic suitability with recent population connectivity and demographic expansion across the Congo Basin. This pattern supports the hypothesis that genetic exchange across the Congo Basin during humid periods, followed by vicariance during arid periods, has shaped regional diversity. Finally, we identified many distinct lineages among our focal taxa, some of which may reflect incipient or unrecognized species.

AB - Organismal traits interact with environmental variation to mediate how species respond to shared landscapes. Thus, differences in traits related to dispersal ability or physiological tolerance may result in phylogeographic discordance among co-distributed taxa, even when they are responding to common barriers. We quantified climatic suitability and stability, and phylogeographic divergence within three reed frog species complexes across the Guineo-Congolian forests and Gulf of Guinea archipelago of Central Africa to investigate how they responded to a shared climatic and geological history. Our species-specific estimates of climatic suitability through time are consistent with temporal and spatial heterogeneity in diversification among the species complexes, indicating that differences in ecological breadth may partly explain these idiosyncratic patterns. Likewise, we demonstrated that fluctuating sea levels periodically exposed a land bridge connecting Bioko Island with the mainland Guineo-Congolian forest and that habitats across the exposed land bridge likely enabled dispersal in some species, but not in others. We did not find evidence that rivers are biogeographic barriers across any of the species complexes. Despite marked differences in the geographic extent of stable climates and temporal estimates of divergence among the species complexes, we recovered a shared pattern of intermittent climatic suitability with recent population connectivity and demographic expansion across the Congo Basin. This pattern supports the hypothesis that genetic exchange across the Congo Basin during humid periods, followed by vicariance during arid periods, has shaped regional diversity. Finally, we identified many distinct lineages among our focal taxa, some of which may reflect incipient or unrecognized species.

KW - climatic refugia

KW - ecological niche modelling

KW - Hyperolius

KW - land-bridge island

KW - lineage divergence

KW - riverine barriers

UR - http://www.scopus.com/inward/record.url?scp=85031718085&partnerID=8YFLogxK

U2 - 10.1111/mec.14260

DO - 10.1111/mec.14260

M3 - Journal article

C2 - 28753250

AN - SCOPUS:85031718085

SN - 0962-1083

VL - 26

SP - 5223

EP - 5244

JO - Molecular Ecology

JF - Molecular Ecology

IS - 19

ER -