Do animals "farm"?

Farming may be defined as the maintenance of crops and/or animals for the supply of food. It is a classical human function that began with the Neolithic Revolution some twelve thousand years ago.

But can non-human animals farm? There is one well-known example in the Animal Kingdom in which it might indeed be claimed that an animal "maintains animals for the supply of food". And that is the maintenance of colonies of aphids by ants to harvest honeydew secretions.

A colony of aphids ("blackfly or greenfly") sucking the sap from a plant stem. These insects are of course hated by gardeners!
Look carefully and you can see some ants crawling over the colony

A closer view of these fascinating little insects that form the bottom
of the food chain as prey for for other insects and birds.
Aphids exude a sweet, sugary secretion called honeydew, much favoured by ants


Zooming in, you can clearly see the ants attending the colony
(two are arrowed, a third is in silhouette on the left)

The ants are not predators of aphids; indeed they maintain them by protecting them from predators such as ladybirds, so as to maintain a continuous supply of the energy rich honeydew; a product of evolution by natural selection.

This appears to be a clear example of one animal (the ant) maintaining another (the aphid) as a supply of food, analogous to the maintenance by humans of cows for milk.

Could you call this "farming"? What do you think?

I took these pictures recently on my travels