Climate change is changing how bugs breed

By Pol Allingham via SWNS

Bugs will thrive in an ever-warming world, suggests a new study.

Researchers discovered damselflies were birthing an extra set of larvae each year to keep up with how rapidly the world’s weather is changing.

Now, the life cycles of the bugs from Michigan in the northeast of the United States mirror that of their southern relatives living in warmer climates and this is successfully keeping them alive.

This contradicts many scientific models that suggest global warming would doom predator-prey species like the damselfly.

The Michigan State University (MSU) team says current predictions on the impact of climate change on animals are unrealistic and don't factor in how critters might behave differently in various temperatures.

Other models only simulated what would happen if damselflies live a one-year lifecycle in a warmer world, concluding they would burn out, die, and potentially become extinct.

But MSU found the bugs could actually thrive if they birth an extra generation each season.

Professor Phoebe Zarnetske, of MSU, said: “We are seeing the pace of climate change is much more rapid than organisms have endured in their evolutionary experience.

“That rapid pace is going to be even more of an issue with the increase in extreme events like heat waves.”

To build the new model, a mathematician worked on observational and experimental work in the field and laboratory to build a more robust model simulating the future for predators and prey.

By studying how temperature changes affect insects in the field, the team believes their predictions are much more realistic.

The research began with Dr. Laura Twardochleb, Professor Zarnetske’s pupil, spending a year watching damselflies' complex lives.

They emerge as adults from ponds in the spring, then mate, reproduce, and the juveniles spend over a year in a pond growing by eating zooplankton.

Dr. Twardochleb saw early models, projecting how warming climates would affect predators like the damselfly, were far simpler than the nature she was observing.

They didn’t allow for the north’s changing seasons and did not keep track of a predator’s size, growth, or how their lifestyle changes with the hotter weather.

The mathematician Professor Chris Klausmeier, a theoretical ecologist at MSU, incorporated Dr. Twardochleb’s observations with his own theory.

He said: “I can make up any model I want, unconstrained by reality.

“But that’s a little dangerous because of course, you want something related to the real world.

"When you join with an experimentalist you can bring not just the experimental results and parameters, but also bring the deep natural history and knowledge to the system to know the key variables and constraints.”

Dr. Twardochleb wrote in Proceedings of the Royal Society B Biological Sciences that the team had laid the ground for future investigations into how species will adapt to a warmer world, particularly disease-carrying mosquitoes.

She added: “A lot of models said predators were going to starve. That’s what’s exciting – that we can make models more realistic.”