Watch for Falling Ants
Did you know some ants are gliders? When Stephen Yanoviak (U. of Texas) was studying insects in the rain forest canopy in Peru, he was struck by the fact that ants kept landing on his arm. This launched his team’s investigation into gliding ants. They took video cameras into the jungle and documented their unique mode of locomotion. They found that the bugs could rotate around and change direction in midair, even when falling like a rock. Most of the time (about 85%) the ants landed back on the tree trunk, able to crawl back up to home. They published their work on “directed aerial descent” in Nature,1 unsure whether the ants were escaping predators or just having fun.
“This is the first study to document the mechanics and ecological relevance of this form of locomotion in the Earth’s most diverse lineage, the insects,” they wrote. A press release on UC Berkeley News tells more about the study, with photographs of the ants and interviews with the research team. How the ants turn around in midair and control their landings is still unknown, but like many insects, they have sticky feet that enable them to cling to many surfaces. “It’s an amazing discovery,” said Robert Dudley of the team. So ants join certain species of squirrels, lizards, frogs and even some snakes (and humans) as gliding champions – this time, in the ultralight class.
1Yanoviak, Dudley and Kaspari, “Directed aerial descent in canopy ants,” Nature 433, 624 – 626 (10 February 2005); doi:10.1038/nature03254.
It seems unlikely that ants would lose their wings through evolution, then re-evolve this behavior as a poor substitute. Surely the power of natural selection would have favored wings evolving again to let the ants fly back home rather than forcing them to walk straight up against gravity. Why select lucky mutations for controlled descent when wings were so easy to evolve? It must have been a piece of cake if they showed up in reptiles, mammals, birds and insects. Didn’t these ants have Haeckel’s recapitulation memory for how to evolve wings all over again? After all, walking sticks did, we are told (see 05/28/2003 entry). “Ah,” young disciples,” Exalted Master Charlie gently scolds, “One must not presume on the path Mother Nature will take. A bumbling tinkerer is She.” So in her toyshop, she apparently forgot how to produce rubber-band airplanes, and decided to make miniature Buzz Lightyears, who mastered the art of “falling with style.”