Geological effects influence population genetic connectivity more than Pleistocene glaciations in the water strider Metrocoris sichuanensis (Insecta: Hemiptera: Gerridae)

TY - JOUR

T1 - Geological effects influence population genetic connectivity more than Pleistocene glaciations in the water strider Metrocoris sichuanensis (Insecta: Hemiptera: Gerridae)

AU - Ye, Zhen

AU - Yuan, Juanjuan

AU - Li, Min

AU - Damgaard, Jakob

AU - Chen, Pingping

AU - Zheng, Chenguang

AU - Yu, Haibin

AU - Fu, Siying

AU - Bu, Wenjun

PY - 2018

Y1 - 2018

N2 - Aim: Palaeoclimatic and palaeogeological events have been identified as two main factors that influence the genetic structuring of extant organisms. We studied a montane stream-dwelling insect, Metrocoris sichuanensis, to explore the relative roles played by these two factors in population genetic connectivity. Location: Sichuan Basin, China. Methods: Mitochondrial (COI, COII, Cytb, 16S) and nuclear (EF-1α, ITS1) markers were sequenced from 208 individuals. Suitable habitat shifts from the Last Glacial Maximum (LGM) to the present were predicted through fine-tuned ecological niche modelling (ENM). Phylogenetic and phylogeographical analyses were conducted to reveal the population genetic structure. Intraspecific divergence and expansion times were estimated using beast. Finally, the least cost path (LCP) method coupled with migrate analysis was used to identify possible dispersal corridors and estimate the asymmetric gene flow. Results: Our ENM results suggested that population habitat connectivity did not change both in the LGM and current conditions. Whole haplotypes were separated into four highly supported clades/haplogroups that exhibited strong geographical structure. The splitting events between the four lineages likely date back to the Early Pleistocene. Bayesian skyline plot (BSP) indicated a moderate demographic growth from the LGM to the present. A putative dispersal corridor was detected along the Longmen Mountains thrust belt, with unidirectional gene flow from north to south. Main conclusion: Our findings support the geographical isolation of the genetic lineages and a deep early Pleistocene split in M. sichuanensis. Landscape connectivity analysis incorporating the genetic data and the ENM prediction revealed that population genetic connectivity was strongly associated with stable climatic habitats shaped by complex topography. The drainage system might have assisted the rapid movement of populations along the Longmen Mountains thrust belt. A strategy for researching the population genetic connectivity of narrow endemics, such as M. sichuanensis, in global biodiversity hotspots is proposed and discussed in this paper.

AB - Aim: Palaeoclimatic and palaeogeological events have been identified as two main factors that influence the genetic structuring of extant organisms. We studied a montane stream-dwelling insect, Metrocoris sichuanensis, to explore the relative roles played by these two factors in population genetic connectivity. Location: Sichuan Basin, China. Methods: Mitochondrial (COI, COII, Cytb, 16S) and nuclear (EF-1α, ITS1) markers were sequenced from 208 individuals. Suitable habitat shifts from the Last Glacial Maximum (LGM) to the present were predicted through fine-tuned ecological niche modelling (ENM). Phylogenetic and phylogeographical analyses were conducted to reveal the population genetic structure. Intraspecific divergence and expansion times were estimated using beast. Finally, the least cost path (LCP) method coupled with migrate analysis was used to identify possible dispersal corridors and estimate the asymmetric gene flow. Results: Our ENM results suggested that population habitat connectivity did not change both in the LGM and current conditions. Whole haplotypes were separated into four highly supported clades/haplogroups that exhibited strong geographical structure. The splitting events between the four lineages likely date back to the Early Pleistocene. Bayesian skyline plot (BSP) indicated a moderate demographic growth from the LGM to the present. A putative dispersal corridor was detected along the Longmen Mountains thrust belt, with unidirectional gene flow from north to south. Main conclusion: Our findings support the geographical isolation of the genetic lineages and a deep early Pleistocene split in M. sichuanensis. Landscape connectivity analysis incorporating the genetic data and the ENM prediction revealed that population genetic connectivity was strongly associated with stable climatic habitats shaped by complex topography. The drainage system might have assisted the rapid movement of populations along the Longmen Mountains thrust belt. A strategy for researching the population genetic connectivity of narrow endemics, such as M. sichuanensis, in global biodiversity hotspots is proposed and discussed in this paper.

KW - drainage system

KW - ENM

KW - geological effects

KW - Metrocoris sichuanensis

KW - narrow endemics

KW - Pleistocene glaciations

KW - Pleistocene stable habitats

KW - population genetic connectivity

KW - Sichuan Basin

U2 - 10.1111/jbi.13148

DO - 10.1111/jbi.13148

M3 - Journal article

AN - SCOPUS:85042462097

SN - 0305-0270

VL - 45

SP - 690

EP - 701

JO - Journal of Biogeography

JF - Journal of Biogeography

IS - 3

ER -