Warming world harming insects' reproduction, says study

By Mark Kinver Environment reporter, BBC News

10 January 2017

A warming world harms insects' ability to reproduce, which could have long-term consequences, scientists warn.

UK researchers also found that insects in northern latitudes were more vulnerable than their southern-dwelling cousins.

The team added that many insects were unable to move great distances while they are juveniles. Therefore, they are at risk from a warming climate.

The findings have been published in the Journal of Evolutionary Biology.

"You get an extreme heat weather event that [the insect] cannot escape from because they are juveniles, so they can't move as much," explained co-author Rhonda Snook from the University of Sheffield, UK. 

"They live through it because it does not kill them, but then they have the subsequent problem of reproducing."

Lasting damage

Dr Snook said the insects in the team's experiments were exposed to a temperature increase of 5.5C (9.9F) for 10 days, which was enough to cause permanent damage to the insects' ability to reproduce.

She said the team was interested in studying the effect of temperature rises in organisms that were unable to move away from their immediate environment.

"Lots of insects in their juvenile stage can't move very far because they are larvae or because they are small nymphs - they are smaller and they do not have wings so they are not as mobile so they're stuck where they are."

Dr Snook told BBC News that the team carried out the experiments on fruit flies but she expected the results to be replicated in many other insects.

"I think that this is going to be a very common effect, a very common phenomenon across insects."

The team examined the effect of increased ambient temperature rise on two populations of fruit flies: one from Spain and another from Sweden.

Continued