Desert locust

Where does the desert locust live?

Home: in deserts, dry grassland and thorn scrub.

In the wild it lives in these countries: Mauritania, Mali, Niger, Sudan, Ethiopia, Saudi Arabia, Yemen, India.

The short profile

Fully grown: 4.5–7 cm long. It weighs about 0 002 kilograms. On the menu: plants.

The story behind it

For most of the time the desert locust lives alone. In this solitary form it is sandy or greenish, moves little and keeps away from others, hidden in the dry belt that runs from Mauritania across the Sahara to north-west India. After good rains the plants grow, many young locusts hatch, and when the green patches shrink again the animals end up crowded onto the same bushes. Their back legs then keep bumping against each other, and that repeated touch sets off a change in the body within a few hours: the insects become active, seek each other out instead of avoiding, and the next generation hatches yellow and black instead of pale green. This crowded form is called gregarious, and it is the swarm form. A big swarm can hold 40 to 80 million locusts in a single square kilometre, fly 100 to 150 kilometres in a day and eat as much plant food in that day as tens of thousands of people would. Warning services in Africa and Asia watch the rainfall and the small groups closely, because preventing a swarm is far easier than stopping one.

Find it on the globe

Desert locust is there as a tiny animated figure that breathes and looks around. From far away the planet is only a blue ball; detail arrives as you zoom in, and this one appears once you are close enough. Open it on the globe.

It sits at its real coordinates, not near them — the same numbers listed in the facts above. Switch off the layer for this kind of place and it disappears again; the buttons for that are down the right-hand edge.