TY - JOUR
T1 - A tale of two conifers
T2 - Migration across a dispersal barrier outpaced regional expansion from refugia
AU - Fernandez, Matias C.
AU - Hu, Feng Sheng
AU - Gavin, Daniel G.
AU - de Lafontaine, Guillaume
AU - Heath, Katy D.
N1 - Funding Information:
We would like to thank Urban M, Lauren L, Chang W, Blyth G, Weintraub L, Napier J, Chipman M, Fernandez JM, Fernandez CL, Fernandez VI, Blitvic N, Burke P, Russell J, Ferguson C, Derr K, and the Cowichan Lake Research Station for their field, laboratory, writing, and analytical assistance. Funding was provided by NSF (DEB‐1146017, and NSF‐GRFP to Fernandez M), and the Graduate College at the University of Illinois. Samples collected in Glacier National Park of Canada under Parks Canada Permit No. GLA‐2013‐14675.
Funding Information:
We would like to thank Urban M, Lauren L, Chang W, Blyth G, Weintraub L, Napier J, Chipman M, Fernandez JM, Fernandez CL, Fernandez VI, Blitvic N, Burke P, Russell J, Ferguson C, Derr K, and the Cowichan Lake Research Station for their field, laboratory, writing, and analytical assistance. Funding was provided by NSF (DEB-1146017, and NSF-GRFP to Fernandez M), and the Graduate College at the University of Illinois. Samples collected in Glacier National Park of Canada under Parks Canada Permit No. GLA-2013-14675.
Publisher Copyright:
© 2021 John Wiley & Sons Ltd
PY - 2021/9
Y1 - 2021/9
N2 - Aim: Understanding how climate refugia and migration over great distances have facilitated species survival during past climate changes is crucial for evaluating contemporary threats to biodiversity, particularly in the face of dispersal barriers. We address this longstanding question on the refugial origins and post-glacial development of mesic forests. Location: Pacific Northwest, North America. Taxon: Mountain hemlock (Tsuga mertensiana) and western redcedar (Thuja plicata). Methods: Range-wide genotyping-by-sequencing (ddRADseq) of both study species and a pollen reconstruction of mountain hemlock presence over the last 20,000 years. Results: Mountain hemlock occurred in two coastal populations (Oregon and Washington) during the glacial maximum, each of which dispersed to the interior (Idaho and British Columbia) during the Holocene. These populations spread in the direction of dominant winds across a barrier of dry, rain-shadowed valleys. In contrast, for western redcedar, we infer four disparate refugia during the glacial maximum: southern (California), central (Washington), interior (Idaho), and northern (Haida Gwaii islands). Main conclusions: Despite the presence of pre-dispersed refugial populations, the majority of the redcedar distribution was colonized by the central population. The history for these two key conifers contrast with many recent studies emphasizing the role of cryptic refugia in colonizing modern species ranges.
AB - Aim: Understanding how climate refugia and migration over great distances have facilitated species survival during past climate changes is crucial for evaluating contemporary threats to biodiversity, particularly in the face of dispersal barriers. We address this longstanding question on the refugial origins and post-glacial development of mesic forests. Location: Pacific Northwest, North America. Taxon: Mountain hemlock (Tsuga mertensiana) and western redcedar (Thuja plicata). Methods: Range-wide genotyping-by-sequencing (ddRADseq) of both study species and a pollen reconstruction of mountain hemlock presence over the last 20,000 years. Results: Mountain hemlock occurred in two coastal populations (Oregon and Washington) during the glacial maximum, each of which dispersed to the interior (Idaho and British Columbia) during the Holocene. These populations spread in the direction of dominant winds across a barrier of dry, rain-shadowed valleys. In contrast, for western redcedar, we infer four disparate refugia during the glacial maximum: southern (California), central (Washington), interior (Idaho), and northern (Haida Gwaii islands). Main conclusions: Despite the presence of pre-dispersed refugial populations, the majority of the redcedar distribution was colonized by the central population. The history for these two key conifers contrast with many recent studies emphasizing the role of cryptic refugia in colonizing modern species ranges.
KW - Pacific Northwest
KW - RAD-Seq
KW - fragmented habitat
KW - long-distance dispersal
KW - migration
KW - postglacial
KW - refugia
UR - http://www.scopus.com/inward/record.url?scp=85109103330&partnerID=8YFLogxK
U2 - 10.1111/jbi.14209
DO - 10.1111/jbi.14209
M3 - Letter
AN - SCOPUS:85109103330
SN - 0305-0270
VL - 48
SP - 2133
EP - 2143
JO - Journal of Biogeography
JF - Journal of Biogeography
IS - 9
ER -