Data from: Nuclear and chloroplast DNA phylogeography reveals Pleistocene divergence and subsequent secondary contact of two genetic lineages of the tropical rainforest tree species Shorea leprosula (Dipterocarpaceae) in Southeast Asia

Tropical rainforests in Southeast Asia have been affected by climatic
fluctuations during past glacial eras. To examine how the accompanying
changes in land areas and temperature have affected the genetic properties
of rainforest trees in the region, we investigated the phylogeographic
patterns of a widespread dipterocarp species, Shorea leprosula. Two types
of DNA markers were used: expressed sequence tag-based simple sequence
repeats (EST-SSRs) and chloroplast DNA (cpDNA) sequence variations. Both
sets of markers revealed clear genetic differentiation between populations
in Borneo and those in the Malay Peninsula and Sumatra (Malay/Sumatra).
However, in the southwestern part of Borneo genetic admixture of the
lineages was observed in the two marker types. Coalescent simulation based
on cpDNA sequence variation suggested that the two lineages arose 0.28 to
0.09 million years before present, and that following their divergence
migration from Malay/Sumatra to Borneo strongly exceeded migration in the
opposite direction. We conclude that the genetic structure of S. leprosula
was largely formed during the middle Pleistocene and was subsequently
modified by eastward migration across the subaerially exposed Sunda Shelf.