How Do These Bugs Walk On Water?

Bugs that Float on Water

There’s a reason Spider-Man is such a popular superhero: Spiders and insects can do a lot of amazing things humans can't. For instance, take the mesmerizing way some bugs can "walk" across lakes, puddles and even streams. Although it looks like magic, this amazing feat is all due to these insects' delicate body structures and the water's surface tension.

To understand how it all works, imagine rain falling on a car windshield. When a drop of rainwater lands, it maintains its droplet shape rather than spreading out evenly across the surface of the glass. This is because the water molecules cling together, giving the droplet a defined outer edge that acts like a microscopically thin skin. Because these water-walking insects are so light, their long, thin legs distribute their weight evenly and prevent them from breaking the surface tension of the water.

Read on to learn more about a few different kinds of bugs that make walking on water look easy.

Water Striders

Water striders — which include insects in the family Gerridae — are one the most common bugs you might see scuttling across the water on your next lake trip. These spider-like insects (pictured above) use their four long, spindly legs to skate across the water, with the back two legs acting like rowing oars. (Their two short front legs are for catching prey.) Their delicate legs are also coated with waxy hairs, which they use to propel themselves forward.

Fishing Spiders

Fishing spiders put each one of their eight legs to good use. Sometimes they "row” their two back legs to skate across the water. Sometimes they jump or bounce off the water's surface tension with their six front legs. The fishing spider can even arrange its back four legs into a sail, which catches the breeze and sends the spider surfing effortlessly across the water.

Mosquitoes

Much like other egg-laying insects, the mosquito’s body is built to float on water. The life cycles of most mosquito species start in the water, whether it be at the edge of a lake or in the standing water of your backyard. Mosquitoes have perfected the art of water landings — they use their thin, flexible bottom-most leg segment, called a tarsus, to rest on the surface of the water long enough to lay their eggs.

So next time you’re at the lake or floating down the river, look closely at the water for these insects — you may be able to spot the tiny “dent” their legs make on the water's surface.