作者：Yanfei Zeng*, Wenting Wang,
Wanjin Liao, Hongfang Wang and Da yong Zhang*
期刊：Molecular ecology
发表时间：2015年
卷.期.页码：24, 5676–5691
摘要：In East Asia, temperate
forests are predicted to have retracted southward to c.30°N during
the last glacial maximum (LGM) based on fossil pollen data, whereas
phylogeographic studies have often suggested glacial in situ survival of
cool-temperate deciduous trees in their modern northern ranges. Here we report
a study of the genetic diversity and structure of 29 natural Mongolian oak (Quercus mongolica) populations using 19
nuclear simple sequence repeat (nSSR) loci and four chloroplast DNA fragments. Bayesian
clustering analysis with nSSRs revealed five groups, which were inferred by
approximate Bayesian computation (ABC) to have diverged in multiple refugia
through multiple glacial–interglacial cycles. Analysis of chloroplast DNA
variation revealed four lineages that were largely but incompletely
geographically disjunct. Ecological niche modelling (ENMs) indicated a
southward range shift of the oak’s distribution at the LGM, although high
suitability scores were also evident in the Changbai Mts. (Northeast China),
the Korean Peninsula, areas surrounding the Bohai Sea, and along the coast of
the Russian Far East. In addition, endemic chloroplast DNA haplotypes and
nuclear lineages occurred in high-latitude northern areas where the ENM
predicted no suitable habitat. The combined evidence from nuclear and
chloroplast DNA, and the results of the ENM clearly demonstrate that multiple
northern refugia, including cryptic ones, were maintained across the current
distributional range of the Mongolian oak during the LGM or earlier glacial
periods. Though spatially limited, postglacial expansions from these refugia
have led to a pattern of decreased genetic diversity with increasing latitude.