As the planet warms up it’s been taken as a given that species will either move northwards or upwards to find temperatures they’re accustomed to (see Nature Reports Climate Change’s ‘The escalator effect’ feature).

The problem of this is after a while no one is left to get on at the bottom. In this week’s issue of Science Robert Colwell and colleagues analyse the hitherto poorly investigated area of tropical species shifts. Using new data from Costa Rica Colwell says that problems for tropical species may face “attrition without parallel at higher latitudes”.

He adds in his paper, “The lowland tropics lack a source pool of species adapted to higher temperatures to replace those driven upslope by warming, raising the possibility of substantial attrition in species richness in the tropical lowlands.”

Another paper in Science also details species movements in response to climate change, this time in Yosemite National Park, where a follow up to a 1918 survey has been done.

“We didn’t set out to study the effects of climate change, but to see what has changed and why,” says Craig Moritz of UC Berkeley (press release).

“But the most dramatic finding in the Yosemite transect was the upward elevational shift of species. When we asked ourselves, “What changed?” it hit us between the eyes: the climate.”

Problematically not all the species in the park have shifted. If change is too rapid “elements of the system may start to collapse because a keystone element of that system gets pulled out too quickly” says fellow researcher James Patton.

More coverage

Climate change may threaten biodiversity in tropics – Reuters

Global warming sending tropical species uphill: study – AFP

Biodiversity in a Warmer World – Science