title: Range and niche shifts in response to past climate change in the desert horned lizard (Phrynosoma platyrhinos).
abstract: During climate change, species are often assumed to shift their geographic distributions (geographic ranges) in order to track environmental conditions - niches - to which they are adapted. Recent work, however, suggests that the niches do not always remain conserved during climate change but shift instead, allowing populations to persist in place or expand into new areas. We assessed the extent of range and niche shifts in response to the warming climate after the Last Glacial Maximum (LGM) in the desert horned lizard (Phrynosoma platyrhinos), a species occupying the western deserts of North America. We used a phylogeographic approach with mitochondrial DNA sequences to approximate the species range during the LGM by identifying populations that exhibit a genetic signal of population stability versus those that exhibit a signal of a recent (likely post-LGM) geographic expansion. We then compared the climatic niche that the species occupies today with the niche it occupied during the LGM using two models of simulated LGM climate. The genetic analyses indicated thatP. platyrhinospersisted within the southern Mojave and Sonoran deserts throughout the latest glacial period and expanded from these deserts northwards, into the western and eastern Great Basin, after the LGM. The climatic niche comparisons revealed thatP. platyrhinosexpanded its climatic niche after the LGM towards novel, warmer and drier climates that allowed it to persist within the southern deserts. Simultaneously, the species shifted its climatic niche towards greater temperature and precipitation fluctuations after the LGM. We concluded that climatic changes at the end of the LGM promoted both range and niche shifts in this lizard. The mechanism that allowed the species to shift its niche remains unknown, but phenotypic plasticity likely contributes to the species ability to adjust to climate change.
authors.affiliation: School of Life Sciences, University of Nevada, Las Vegas, 4505 South Maryland Parkway, Las Vegas, Nevada, 89154-4004, USA; Department of Ecology and Evolutionary Biology, University of Arizona, P.O. Box 210088, Tucson, Arizona, 85721-0088, USA.
authors.forename: Tereza
authors.initials: T
authors.lastname: Jezkova
authors.affiliation: School of Life Sciences, University of Nevada, Las Vegas, 4505 South Maryland Parkway, Las Vegas, Nevada, 89154-4004, USA.
authors.forename: Jef R
authors.initials: JR
authors.lastname: Jaeger
authors.affiliation: School of Life Sciences, University of Nevada, Las Vegas, 4505 South Maryland Parkway, Las Vegas, Nevada, 89154-4004, USA.
authors.forename: Viktória
authors.initials: V
authors.lastname: Oláh-Hemmings
authors.affiliation: Desert Research Institute, Division of Earth and Ecosystem Sciences, 755 East Flamingo Road, Las Vegas, Nevada, 89119, USA.
authors.forename: K Bruce
authors.initials: KB
authors.lastname: Jones
authors.affiliation: Department of Ecology and Evolutionary Biology, University of California Santa Cruz, 1156 High Street, Santa Cruz, California, 95064, USA.
authors.forename: Rafael A
authors.initials: RA
authors.lastname: Lara-Resendiz
authors.affiliation: Smithsonian Institution, PO Box 37012, MRC 162, Washington, DC, 20013-7012, USA.
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Mulcahy
authors.affiliation: School of Life Sciences, University of Nevada, Las Vegas, 4505 South Maryland Parkway, Las Vegas, Nevada, 89154-4004, USA.
authors.forename: Brett R
authors.initials: BR
authors.lastname: Riddle
keywords: Great Basin; Last Glacial Maximum; niche assessment; niche shift; non-analog climate; range expansion