Charles Darwin was right about why insects lost the ability to fly

Most insects can fly.

However, many species have lost this exceptional ability, especially on islands.

On small islands located midway between Antarctica and continents like Australia, nearly all insects have done so.

Flies walk, and moths crawl.

“Of course, Charles Darwin was aware of the habit of losing these island insects’ wings,” says PhD. Candidate Rachel Leahy from Monash University’s School of Biological Sciences.

“He and the famous botanist Joseph Hooker had a fundamental argument as to why this happened. Darwin’s position was deceptively simple. If you travel, you will explode at sea. Those left on Earth to produce the next generation are the most reluctant to fly, and ultimately evolution does the rest .

But since Hooker expressed his doubts, many other scholars have shown so, too.

In short, they simply said that Darwin was wrong.

Yet almost all of these discussions ignored the setting that exemplifies the loss of flight – those “sub-Antarctic” islands. Located in the “roaring forties” and “furious fifties”, it is one of the windiest places on earth.

“If Darwin really makes a mistake, the wind in no way will explain why so many insects have lost their ability to fly on these islands,” said Rachel.

Using a large, new dataset on insects from the Antarctic and Arctic regions carrots, Monash University researchers have examined every idea proposed to explain fly loss in insects, including Darwin’s idea of ​​wind.

Reports today at Proceedings of the Royal Society b, They showed that Darwin was right in “the windiest places”. None of the usual ideas (like the one proposed by Hooker) explain how lost flight in sub-Antarctic insects is, but Darwin’s idea does. Although in a slightly varied form, in line with modern ideas of how flight loss actually evolved.

Windy weather conditions make the insects’ journey more difficult and energy-expensive. And so on , Insects Stop investing in it Flight Expensive basic machines (wings and wing muscles) redirect resources for reproduction.

“It is remarkable that after 160 years, Darwin’s ideas continue to provide insight into the environment,” said lead author Rachel.

Professor Stephen Chun, also from the School of Biological Sciences, added that the Antarctic region is an exceptional laboratory for solving some of the world’s most enduring mysteries and testing some of its most important ideas.