Open AccessEvolutionary response to Q uaternary climate aridification and oscillations in north‐western C hina revealed by chloroplast phylogeography of the desert shrub N itraria sphaerocarpa ( N itrariaceae)
Author(s) -
Su Zhihao,
Zhang Mingli
Publication year - 2013
Publication title -
biological journal of the linnean society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.906
H-Index - 112
eISSN - 1095-8312
pISSN - 0024-4066
DOI - 10.1111/bij.12088
Subject(s) - aridification , biology , ecology , phylogeography , range (aeronautics) , shrub , mantel test , genetic diversity , climate change , population , genetic variation , phylogenetic tree , demography , biochemistry , gene , materials science , sociology , composite material
To investigate the influence of climate aridification and oscillations on the genetic diversity and evolutionary processes of organisms in the Q uaternary in north‐western C hina, we selected N itraria sphaerocarpa and examined the phylogeographical structure and response to historical and environmental factors in populations of this species across most of its covered range. We found twelve haplotypes on the basis of two chloroplast DNA sequences ( trn H ‐psb A and rpl 32 ‐trn L ). The drying climate during the Q uaternary is proposed to have been a driver for significant genetic isolation and divergence among populations in N . sphaerocarpa . Except for the sharing of haplotype D between the H ami B asin and H exi C orridor, as well as of haplotype F between the H exi C orridor and A lxa D esert, network analysis showed haplotypes to be almost completely different from region to region. Analysis of molecular variance indicated that genetic variation primarily occurred among populations and among nine geographical groups that were distinguished by spatial analysis of molecular variance, and a M antel test showed that the correlation between genetic and geographical distances was significant. On the other hand, there was evidence for the occurrence of an episode of more favourable conditions in some regions. Geographical range expansion of two groups of N . sphaerocarpa populations was supported by significant values for F u's F S and unimodel mismatch distributions. During the last interglacial period, a warmer and wetter climate contributed to range expansion within portions of the H exi C orridor. By contrast, based on ecological niche modelling, N . sphaerocarpa was indicated to have had a shrunken and more fragmented range during the L ast G lacial M aximum. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society , 2013, 109 , 757–770.