Climate change drives animals uphill

Animals overheated by climate change are heading uphill and away from the equator, a new study has found.

A range of studies in recent years have suggested that some species are relocating to higher ground and farther from the equator in a bid to remain cool in the face of global temperature rises driven by climate change. But to what extent this migration is comprehensive and global across species was not known.

Now York University scientist Chris Thomas and his colleagues have confirmed, in a paper in Science, that animals really are on the move. The researchers performed a meta-analysis, collating the results of a large number of previous studies that had monitored the movements of over 2000 species, to show that animals are moving uphill at the rate of about 11 metres per decade and shifting their ranges away from the equator an average of 16.9 kilometres over the same period.

These numbers are far larger than those advanced by previous studies. The team cross-checked their results by making predictions of the scale of a species' movements based on the temperature changes in different geographical areas, and then comparing these predictions with the real observations. The two tallied strongly.

There are some exceptions to the rule, with up to 25% of species bucking the general trend, like birds for instance, although accounting for these anomalies is outside the scope of this study. It's also unsurprising since the movement of one species may open up niches or reduce the stress on another species, enabling it to stay put.

The impact of the finding is highly significant and may also have clinical implications for human health as non-native animals move into new terrains, potentially bringing a host of diseases with them...