Global Warming, Elevational Range Shifts, and Lowland Biotic Attrition in the Wet Tropics

Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT 06269, USA.
Science (Impact Factor: 31.48). 11/2008; 322(5899):258-61. DOI: 10.1126/science.1162547
Source: PubMed

ABSTRACT Many studies suggest that global warming is driving species ranges poleward and toward higher elevations at temperate latitudes,
but evidence for range shifts is scarce for the tropics, where the shallow latitudinal temperature gradient makes upslope
shifts more likely than poleward shifts. Based on new data for plants and insects on an elevational transect in Costa Rica,
we assess the potential for lowland biotic attrition, range-shift gaps, and mountaintop extinctions under projected warming.
We conclude that tropical lowland biotas may face a level of net lowland biotic attrition without parallel at higher latitudes
(where range shifts may be compensated for by species from lower latitudes) and that a high proportion of tropical species
soon faces gaps between current and projected elevational ranges.

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Available from: Gunnar Brehm, Aug 28, 2015
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    • "If temperature increases in lowland forest are sufficient to affect reproduction and survival of many species, then populations could certainly decline, particularly given that there would be little opportunity to move to higher elevations or latitudes (see Colwell et al., 2008). Global temperature has apparently increased at a rate of ∼0.2 • C/decade since 1975 (Hansen et al., 2006) with an increase of ∼0.25 • C/decade in lowland tropics (cited in Colwell et al., 2008). If correct, then we might expect to see increases of ∼0.12 to ∼0.15 • C during 5–7 years (i.e., from 2008 to 2014). "
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    • "It was observed recently that the mating frequency in a tettigonid bush-cricket, Metrioptera roeselii, increased towards higher latitudes (Kaňuch et al. 2013). Although field-based results do not allow for elucidating mechanisms behind the variation that was found, one can expect that observed patterns may be similar also along an altitudinal gradient because many ecological factors that correlate with latitude also correlate with altitude (Colwell et al. 2008; Taylor et al. 2014). "
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