Connect with us


As mountains grow, they drive the evolution of new species

aren’t just beautiful: these locales also tend to host some of
the richest diversity of species on the planet. We’ve known
this for a long time—ever since Alexander von Humboldt, the
Prussian geographer and naturalist, first climbed up the Andes
in the 18th century. But nobody has really figured out why.

One popular hypothesis goes like this: the reason why mountains
have so many different species is that, as mountains are
uplifted by colliding tectonic
, the process creates more environments, and
therefore more opportunities for new species to adapt to them.
However, this hypothesis never had any explicit quantitative
testing until now, according to
a recent study
published in the Proceedings of the
National Academy of Sciences

Many other studies have looked at the diversity of one single
plant group or another, and results seemed to support the
popular hypothesis. “That claim is often made. The hypothesis
often incorporates the narratives of these studies, but it’s
never been explicitly tested” across time and space, through
quantitative comparison, says study co-author Richard
, Associate Curator of Botany at Chicago’s Field Museum.

Ree and colleagues found that as China’s Hengduan mountains
formed eight million years ago, the rate of diversification
there was more than twice as fast as that found in the
Himalayas—which are quite close by, but much older—during the
same stretch of time.

The Hengduan Mountains are pretty young, geologically
speaking—the Himalayas
are more than twice as old, having formed around 20 million
years ago. But the spot is bursting with biodiversity: the
younger mountains play host to more than one third of the
30,000 species of vascular plants (basically everything except
mosses) found across China, says Ree.

Colin Hughes
, an assistant professor at the Department of
Systematic and Evolutionary Botany at the University of Zurich
who was not involved in the study, says the researchers “have
made a significant step forward.”

“We’ve known that part of the world is very diverse since the
19th century,” Hughes says. “But nobody understood the
evolutionary history of this hotspot in any general way until
now, so this is a landmark study.”

Continue Reading
You may also like...

From the streets of Los Angeles to the other side of the world. We are RR-Magazine


More in Technology

To Top