Ant secret : How do ants crawl on a wall?

Their grip is sticky, sharp, anti-gravity.

(Debby Cassill: Associate Professor of Integrative Biology, University of South Florida)


New York, Sept. 14 (The Conversation) When I started my job as a biologist at the University of South Florida, I took my Jeep to a grass field and there Dig up a mound of red ants and fill them with a shovel into a 5 gallon bucket.

Thousands of ants, which came out of the soil, immediately started climbing around the bucket to get out of it.

Luckily I had a lid.

Seeing them, how could ants climb walls, ceilings and other surfaces so easily?

I've been studying ants for 30 years, and their climbing ability always amazes me.

Working ants, which are all female, have an impressive toolbox of claws, spines, hairs and sticky pads on their feet that enable them to climb almost any surface.

human hand vs ant foot

To understand the feet of an ant, it helps to compare them with human hands.

You have a wide section of your hand, the palm.

Four fingers and an opposite thumb come out of your palm.

Each finger has three segments, whereas your thumb has only two segments.

A hard nail grows from the tips of your fingers and thumb.

Humans have two hands, ants have six legs.

Ant legs are similar to your hands, but are more complex, with an additional set of strange-looking parts that propel them forward.

Ant legs have five jointed segments, the last segment having a pair of claws.

The claws are similar to the claws of a cat and can grip walls.

Each leg segment also has thick and thin spines and hairs, which provide additional grip by clinging to microscopic pits on the bark-like textured surfaces.

Claws and spines provide the added benefit of protecting ants from hot surfaces and sharp objects, as do your feet with shoes.

But the feature that really differentiates human hands from ant feet is a sticky pad called areolea.

sticky feet

The areolea are located between the claws at the tip of each ant's foot.

These balloon-like pads help the ants defy gravity and crawl on ultrahard surfaces such as ceilings or glass. When an ant walks on a wall or ceiling, gravity causes its claws to spread wide and pull back. Huh. 

At the same time, its leg muscles pump fluid into the pads at the end of the feet, causing them to swell.

This fluid is called hemolymph, a viscous fluid similar to your blood that circulates in an ant's body.

After the hemolymph pad is pumped, some of it leaks outside the pad, allowing ants to stick to the wall or ceiling.

But when an ant lifts its leg, its leg muscles contract and suck most of the fluid back into the pad and then raise the leg.

In this way an ant uses that fluid over and over again - it is pumped from the foot into the pad, then sucked back - so that nothing is left behind.

The ants' six sticky pads are enough to hold them against the pull of gravity on any surface.

In fact, in their underground chambers in the house, ants use their sticky pads to sleep on the ceiling.

a strange trick

When you walk, your left and right legs move forward one by one, so one is on the ground while the other is in the air, leading.

Ants also place their feet alternately, three on the surface and three in the air at once.


The way ants walk is unique among six legged insects.

In ants the front and rear left feet are on the ground with the middle right foot, while the front and back right foot and middle left foot are in the air.

Then they switch.

It's fun trying to copy this triangular pattern using three fingers on each hand.

Next time you see an ant crawling on a wall, watch it carefully and enjoy its fascinating features.