This is a scientific Americans 60 second science. I'm Jason Goldman.

Make a left at the big oak tree about a mile down the road.

That kind of direction is common in landscapes filled with visual cues.

But the Sahara Desert is a much tougher place to navigate.

Even any footprints you leave get erased as winds massage the sand.

Nevertheless, ants in the desert go on searches for food,

and once they find it, they carry their prize directly back to the nest. In the late 1980s,

researchers discovered that the ants can achieve this impressive feat using a process called path integration.

To gauge the direction home, to keep track of the sun's motion across the sky, just like sailors used to do.

To calculate the distance that count their steps.

It's a very hostile environment.

They are foraging at the hottest times of the day and it's a desert so surface temperatures reach 60 to 70 degrees Celsius.

Neurobiologist Matias Whitlinger from Germany's own university on the podcast of the journal Science which published this work.

And they need to be really quick in finding food and they really need to be very quick in get the food back to the nest.

They need to be really fast and they are traveling at speeds of 100 body length per seconds.

Wintinger noticed that sometimes desert ants carry each other.

And here we had like this unique opportunity to test traveling ants that are not walking.

If they're not walking, then they can't count their steps. So would these ants be able to find their way home?

Bees and wasps can't count their steps because they fly.

Instead, to estimate distance, they rely on what's called optic flow,

which tracks how much visual information flows past them while they travel.

So do carried ants also use optic flow?

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