Main content

Ants and acacias - a top team

'The interaction between insects and plants is what Life on Earth was all about. Some ants are positively encouraged by acacia trees to live amongst them.

'The interaction between insects and plants is what Life on Earth was all about. This fascinating story is one of many, and one I studied myself in Africa whilst working for Oxford University.' (George McGavin)

Some ants have a relationship with acacia trees and are positively encouraged by the tree to live there.

Acacia trees in Central America, for example, produce tough thorns in which colonies of aggressive stinging ants make their home.

Each pair of thorns has a hole at the tip of one of them for the ants to enter and chew away at the spongy cells inside until they have made a strong and safe nest for their eggs and developing larvae.

The ants never have to leave the tree to feed as the tree provides the colony with a beautifully balanced diet.

The reddish brown beads on the leaflet tips are rich in fats, proteins and vitamins, and although the beads have no real function for the tree itself, they are ideal food for developing insects.

As the beads develop at the tips of the tender new leaves and on the tips of new shoots, the stinging ants are ideally placed to defend the most vulnerable part of the plant.

In return, the acacia also produces nectar from the base of its leaves, the sole function of which is to produce sugar for the ants. The ferocious ants repay the favour by defending the tree from other insects, and driving off any large grazing animals.

They will even kill vines that try to climb the tree.

Release date:

Duration:

2 minutes

Featured in...