Article (Scientific journals)
Large-scale pattern of genetic differentiation within African rainforest trees: insights on the roles of ecological gradients and past climate changes on the evolution of Erythrophleum spp (Fabaceae)
Duminil, Jérôme; Brown, Richard P.; Ewédjè, Eben-Ezer BK. et al.
2013In BMC Evolutionary Biology, 13, p. 195
Peer Reviewed verified by ORBi


Full Text
Publisher postprint (1.13 MB)

All documents in ORBi are protected by a user license.

Send to


Keywords :
Cluster analysis; Fragmentation; Last glacial maximum; Phylogeography; Range expansion; Refugium; Species delimitation; Tropical rainforest
Abstract :
[en] Background: The evolutionary events that have shaped biodiversity patterns in the African rainforests are still poorly documented. Past forest fragmentation and ecological gradients have been advocated as important drivers of genetic differentiation but their respective roles remain unclear. Using nuclear microsatellites (nSSRs) and chloroplast non-coding sequences (pDNA), we characterised the spatial genetic structure of Erythrophleum (Fabaceae) forest trees in West and Central Africa (Guinea Region, GR). This widespread genus displays a wide ecological amplitude and taxonomists recognize two forest tree species, E. ivorense and E. suaveolens, which are difficult to distinguish in the field and often confused. Results: Bayesian-clustering applied on nSSRs of a blind sample of 648 specimens identified three major gene pools showing no or very limited introgression. They present parapatric distributions correlated to rainfall gradients and forest types. One gene pool is restricted to coastal evergreen forests and corresponds to E. ivorense; a second one is found in gallery forests from the dry forest zone of West Africa and North-West Cameroon and corresponds to West-African E. suaveolens; the third gene pool occurs in semi-evergreen forests and corresponds to Central African E. suaveolens. These gene pools have mostly unique pDNA haplotypes but they do not form reciprocally monophyletic clades. Nevertheless, pDNA molecular dating indicates that the divergence between E. ivorense and Central African E. suaveolens predates the Pleistocene. Further Bayesian-clustering applied within each major gene pool identified diffuse genetic discontinuities (minor gene pools displaying substantial introgression) at a latitude between 0 and 2°N in Central Africa for both species, and at a longitude between 5° and 8°E for E. ivorense. Moreover, we detected evidence of past population declines which are consistent with historical habitat fragmentation induced by Pleistocene climate changes. Conclusions: Overall, deep genetic differentiation (major gene pools) follows ecological gradients that may be at the origin of speciation, while diffuse differentiation (minor gene pools) are tentatively interpreted as the signature of past forest fragmentation induced by past climate changes.
Disciplines :
Genetics & genetic processes
Phytobiology (plant sciences, forestry, mycology...)
Author, co-author :
Duminil, Jérôme
Brown, Richard P.
Ewédjè, Eben-Ezer BK.
Mardulyn, Patrick
Doucet, Jean-Louis ;  Université de Liège - ULiège > Forêts, Nature et Paysage > Laboratoire de Foresterie des régions trop. et subtropicales
Hardy, Olivier J.
Language :
Title :
Large-scale pattern of genetic differentiation within African rainforest trees: insights on the roles of ecological gradients and past climate changes on the evolution of Erythrophleum spp (Fabaceae)
Publication date :
12 September 2013
Journal title :
BMC Evolutionary Biology
Publisher :
BioMed Central
Volume :
Pages :
Peer reviewed :
Peer Reviewed verified by ORBi
Available on ORBi :
since 07 January 2014


Number of views
54 (7 by ULiège)
Number of downloads
180 (3 by ULiège)

Scopus citations®
Scopus citations®
without self-citations


Similar publications

Contact ORBi