How does an ant find home with no trail to follow?

Some ants walk home on their own, with no trail to follow. Desert ants do it by counting their steps as they walk. They also check the sun to know which way they're heading. Put together, the steps and the sun tell them which way home is, and how far.

How do we know ants count their steps?

Scientists tried a clever test with desert ants. They glued tiny bristles onto some ants' feet, like stilts, to make their legs longer. Those ants walked about five metres right past their home! Their steps were bigger, but they took the same number. So the ants must be counting steps.

How do ants find their way home?

Lue answers for ages 4–11, then goes 2 steps deeper each time a child asks why.

Lue says

When an ant finds food, it heads home and leaves a smelly trail along the way. Other ants sniff out the trail with their feelers and follow it to the food. Each one adds more smell as it goes. So the trail gets stronger, and soon there's a long line of ants marching back and forth.

For ages 4–7

Checked against Why and how do ants walk in a perfect line? (CU Boulder Today)
How does an ant find home with no trail to follow?

Some ants walk home on their own, with no trail to follow. Desert ants do it by counting their steps as they walk. They also check the sun to know which way they're heading. Put together, the steps and the sun tell them which way home is, and how far.

For ages 6–9

Checked against Orientation of ants: every cue counts (Max Planck Society)
How do we know ants count their steps?

Scientists tried a clever test with desert ants. They glued tiny bristles onto some ants' feet, like stilts, to make their legs longer. Those ants walked about five metres right past their home! Their steps were bigger, but they took the same number. So the ants must be counting steps.

For ages 8–11

Checked against Ant navigation: stride matters (The Christian Science Monitor)