Insects around the world are experiencing fertility issues and the heatwaves caused by climate change are to be blamed.
A new study revealed that exposure to heatwaves caused damages to the sperm of male beetles, making them sterile. This adds to the growing list of the negative effects of climate change to biodiversity.
How Climate Change Is Cutting Down Insect Population
"We know that biodiversity is suffering under climate change, but the specific causes and sensitivities are hard to pin down," explained Matt Gage of the University of East Anglia and the research group leader. "We've shown in this work that sperm function is an especially sensitive trait when the environment heats up, and in a model system representing a huge amount of global biodiversity."
The study used red flour beetle and exposed them to either standard control conditions or heatwave temperatures. Afterward, the researchers assessed how the heatwaves affect the reproductive success of the insects, including their sperm function and offspring quality.
They found that after exposure to heatwaves, the sperm production of the male beetles reduced by three-quarters. Moreover, they found that the sperm from the male beetles struggled to move to the female beetles' tract. It means, there is a greater chance that the sperm does not survive to fertilize the egg.
In addition, the study also revealed that exposure to heatwaves caused male beetles to mate less frequently, contributing to a potential decline in the species' population.
The researchers used beetles as a test subject because there are about 400,000 species of the insects around the world. Beetles constitute 25 percent of all known animal species.
Lasting Effects Of Heatwave Exposure
Perhaps more concerningly, exposure to heatwaves has lasting effects to the lifespans and reproductive activities of the beetles' offsprings. The sons of the male beetles exposed to heatwaves for the experiment lived a couple of months shorter than average. They were also able to fertilize far less female beetles and produced significantly fewer offsprings of their own.
It has been suspected that climate change is driving the collapse of insect biodiversity around the world, but how it is affecting biodiversity is still poorly understood. The researchers hope that further studies shall be done on whether climate change is a factor in the massive decline of insect populations worldwide.
The study was published in the journal Nature Communications.