But most of these studies have looked at a limited number of species or a narrow geographic region, making it hard to put together a clear picture of global trends. Now, a study has combined a lot of the individual ones into a meta-analysis, and finds that species are shifting habitat faster than we had assumed, but aren't all moving towards cooler climes.
The authors looked at two classes of studies, ones that focused on changes in altitude (plants and animals moving uphill) and others that focused on changes in latitude, as species respond to a warming world by moving towards the poles. Although the result is a bit more global, it's still heavily biased towards Europe and North America (with Chile and Malaysia also making appearances). Still, the studies are enough to include over 1,300 species, which the authors consider in 23 distinct groups, divided by taxonomy and geography (in the authors' example, plants in Switzerland).
The mean travel poleward of all the species included in these studies was 17km a decade; vertically, the mean had a species moving 11m uphill. That's not especially speedy, but it's still two to three times faster than previous estimates had placed on these values. And over several decades, those kilometers can add up. Perhaps more significantly, two different tests indicated that species were moving the fastest in areas that are experiencing greater temperature changes. Read the full report here.
Source: by John Timmer, ARS Technica.
