Science with Dr Karl: Ants are Strong AND Clever

Dr Karl investigates ants and their behaviour

Did you know that ants can only lift or drag a heavy load? They don’t do a lot of pushing… So how do they manage to manoeuvre a big piece of tasty food back to their nest so efficiently?

Let’s consider an ant stumbling across a cat’s dinner. It can’t move all the food by itself, so it rushes back to its nest to get help, all the way squirting out a special chemical called a pheromone. This pheromone guides the other ants
to where the food is.

The other ants sniff the pheromone carefully with their antennae, and head towards the cat food. Very soon there’s a trail of individual ants carrying the small bits of food back to the nest. But what about the larger lumps?

A group will work together, with their heads and antennae tightly pressed up against the food. Then they’ll start lifting and dragging. At first, they’ll have an idea of where the nest is – thanks to the pheromone trail. But the ants can’t see because their sensing antennae are pushed up against the food. Without a leader guiding them, the ants will soon lose track of where they are going!

Luckily, another ant close by will cross the pheromone trail and determine where the nest is. She will then join the group of ants and start lifting and dragging the lump of food in the direction of the nest. She is now the leader, or steerer. Because she is near the front end of the food, she is able to direct the ants towards the nest – but only for a while. After about 10-20 seconds, she won’t know where the nest is anymore, because her antennae is now pressed against the food, and she can’t see where she’s going. So she is replaced by another ant that has just crossed the pheromone trail. This new ant will know where the nest is – and now she will help steer the load. This process will repeat until the food is safely at the nest… for all the ants to enjoy! Go team!

DID YOU KNOW? Ants are famous for their amazing individual strength. The allegheny mound ants in North America are among the strongest in the world. They can lift 1,000 times their own weight! That’s equivalent to an 80kg person lifting a fully loaded Boeing 737! Impressive!

DID YOU KNOW? Ants are one of the few creatures (besides humans) that cooperate to both build things together and shift loads much heavier than they can lift single-handedly.

DID YOU KNOW? The Asian weaver ant can carry more than 100 times its own body weight – whilst standing upside down on the bottom of a glass!