Insects and us: a mind-blowing 20 quadrillion ants and what they mean for the planet

There are 2.5m of these tiny creatures for each human and they play a big role as ecosystem engineers, as well as providing insights on everything from the climate to ageing

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To most of us, they are small, uninteresting and sometimes annoying, but 2022 revealed just how ubiquitous ants are and how indispensable they are to the planet. Scientists revealed in September that there are an estimated 20 quadrillion (or 20 million billion) ants globally - that's 2.5 million for every person on the planet.

More than 12,000 known species of ant live in all sorts of habitats, from the Arctic to the tropics and they represent one of the most diverse, abundant and specialist groups of animals on the planet. Leafcutter ants are fungus farmers, slave-making ants capture broods to increase their work force, while wood ants herd aphids to the juiciest parts of a plant to harvest their honeydew sap.