Animal Adaptations

A favorite animal adaptation of mine are halteres

By Rob Breeding

The natural world is filled with remarkable innovation.

A favorite animal adaptation of mine are halteres. Well, not mine, but of flies. True flies, actually, a group that includes houseflies and mosquitoes.

Halteres are small, club-like appendages where the hind wings are found in other insects. Halteres function like gyroscopes, helping flies maintain balance and direction as they perform their aerial acrobatics evading swatter-wielding humans.

Many of the best fliers in the bug world are true flies. As annoying as houseflies are, I’m always amazed by their aerial skills. Even more impressive are hoverflies, bugs you’ve seen flying still in flower gardens in summer. Many look just like bees, with yellow and black striped abdomens, but bees are graceless fliers in comparison.

Bees sport a full set of four wings and are designed for hauling pollen cargo back to the hive.

Hoverflies are important native pollinators and their larvae are often predators of garden pests. It’s always a good idea to grow some flowering plants in the vegetable garden to attract hoverflies.

It’s disappointing to be reminded mosquitoes are also true flies. I despise mosquitoes with all their biting and disease spreading ways, though I admit some enemies are worthy of respect. Not mosquitoes. Any species that wastes an adaptation as amazing as halteres by flying so clumsily deserves contempt.

Whacking a housefly with a swatter presents a sporting challenge. The only challenge to swatting a mosquito is that usually you have to climb out of a warm bed to do so when one buzzes you at night.

A bug doesn’t need halteres to hover, though they surely help. Dragonflies are possibly the greatest of all flying insects since they hunt other great fliers on the wing. Like bees, dragonflies also have all four wings, which they hold straight out from their sides at rest. They are a particularly ancient insect, as the fossil record tells us dragonflies with 30-inch wingspans shared the planet with dinosaurs.

The sight of a dragonfly that big hovering and zipping about would be nearly as terrifying as having a Tyrannosaurus rex crash your summer picnic at the lake.

True hovering is a rare skill. Most hovering masters are insects, critters small enough to handle the required energy demands.

Speed generates lift, which assists most fliers in staying aloft. Hoverers get no speed assist and that requires a lot of extra work. Only two vertebrates are true hoverers: hummingbirds and nectar-eating bats.

Hummers are more efficient hoverers than bats. Despite their tiny size, hummingbirds have outsized breast muscles in comparison to other birds. They also possess yoga-like flexibility, allowing them to twist their wings to create lift without generating forward motion. With a slight adjustment of wing angle, hummers also fly backward.

Bats make up for their relative lack of agility with larger wings and more powerful strokes.

We’ve all seen hawks and other birds of prey “hover” as they hunt, but this isn’t hovering in the classic sense. Birds of prey use air currents to stay in place. Hummers generate all the necessary lift themselves.

Fall isn’t far off, and its cool arrival ushers away most of the hoverers of the north via hibernation, migration or death. But there are animal adaptations that allow the species that linger through winter to cope with the cold. The insulative hollow hair of deer and elk, for instance.

Another northern adaptation are the wide feet of lynx that act as snowshoes so these cats become more efficient predators atop a layer of white stuff.

But for me, nothing quite beats halteres. Next summer I’m going to replace my fly swatter with one of those salt blasting toy fly guns.

After all, a hunter is best measured against the skill of its prey.

Rob Breeding is the editor of www.mthookandbullet.com.