Charles Darwin was right about why insects are losing their ability to fly

Most insects can fly.

Yet many species have lost that extraordinary ability, especially on the islands.

On the smaller islands that lie between continents such as Antarctica and Australia, almost all insects have done so.

The flies move, the moths crawl.

“Of course, Charles was aware of the habit of losing this wing of Darwin Island insects,” the Ph.D. Rachel Lehi, a candidate from Monash University School Bif Biological Sciences.

“He and the famous botanist Joseph Hooker had a remarkable argument as to why this happens. Darwin’s position was deceptively simple. If you fly, you will fly into the ocean. More hesitant, and eventually evolution does the rest.

But since Hooker expressed his skepticism, so have many other scientists.

In short, they simply say that Darwin did it wrong.

However, all these discussions have overlooked the location that is characteristic of flight losses – those ‘sub-Antarctic’ islands. Speaking in ‘Roaring Forties’ and ‘Angry Fifties’, they are the most windy place on earth.

“If Darwin really did it wrong, the wind would in no way explain why so many insects have lost the ability to fly on these islands.”

Using large, new datasets on insects from the sub-Antarctic and Arctic islands, researchers at Monash University examined a proposal responsible for flight losses in insects, including Darwin’s idea of ​​wind.

Report today Proceedings of the Royal Society b, They show that Darwin was right for this ‘atmosphere of places’. None of the common ideas (as suggested by Hooker) can explain the extent of flight damage in sub-Antarctic insects, but Darwin thinks so. Although in a slightly varied form, given the modern ideas of how flight damage develops.

Wind conditions make insect flight more difficult and expensive to get. Thus, insects stop investing in flight and redirect its costly underlying machinery (wings, wing muscles) and resources to reproduction.

“It’s remarkable that even after 160 years, Darwin’s ideas continue to make sense to ecology,” said Rachel, the paper’s lead author.

Steven Cowen, a professor at the School of Biological Sciences, added that the Antarctic region is an extraordinary laboratory for solving some of the world’s most enduring mysteries and testing some of its most important ideas.