Only in the long run; short-term outlook is for species loss
By Summit Voice
FRISCO — An analysis of fossil and geological records going back 540 million years suggests that, in general, the Earth’s biodiversity has increased during interglacial warm periods — but only in the long run, depending on the evolution of species over millions of years.
Short-term, the current warming trend is likely to cut biodiversity, in part because of the pace of climbing temperatures, according to researchers from the universities of York, Glasgow and Leeds.
“The improved data give us a more secure picture of the impact of warmer temperatures on marine biodiversity and they show that, as before, there is more extinction and origination in warm geological periods,” said Dr. Peter Mayhew, of the Department of Biology at York. “But, overall, warm climates seem to boost biodiversity in the very long run, rather than reducing it.”
The study, published in Proceedings of the National Academy of Sciences found that, while warm periods in the geological past experienced increased extinctions, they also promoted the origination of new species, increasing overall biodiversity.
“The previous findings always seemed paradoxical. Ecological studies show that species richness consistently increases towards the Equator, where it is warm, yet the relationship between biodiversity and temperature through time appeared to be the opposite. Our new results reverse these conclusions and bring them into line with the ecological pattern,” said Dr. Alistair McGowan, of the School of Geographical and Earth Sciences at the University of Glasgow.
“Science progresses by constantly re-examining conclusions in the light of better data. Our results seem to show that temperature improves biodiversity through time as well as across space,” said Professor Tim Benton, of the Faculty of Biological Sciences at the University of Leeds. “However, they do not suggest that current global warming is good for existing species. Increases in global diversity take millions of years, and in the meantime we expect extinctions to occur.”