Ants farm aphids in a symbiotic relationship

© Ants: Natures secret power

Many ants have developed a variety of symbiotic relationships with other invertebrates and plants, sometimes to mutual benefit, sometimes not.

One of the most common is the herding or farming of sap feeding insects ‘homopterans’ such as aphids, scale bugs and mealy bugs.

These insects obtain their own food from plants and pass some of it on to the ants as highly nutritious nectar or honey dew. In return, the ants tenderly look after and protect them from predators.

By stroking the back of some aphids with their antennae, the ants can induce a honeydew droplet.

The ants may move the insects to areas on the plants with the best sap.

When it rains they may move them to sheltered places, even sometimes into their own nests.

Although this process seems very pleasant for both parties, recent studies show that ants sometimes clip the wings off aphids to stop them flying away. They also use chemicals found on their feet to drug them, preventing their wings from developing. It appears that the ants are very much in charge. ()

© BBC Worldwide