What is a pedometer? It is this fashionable device that allows us to count the steps we take. People who play sports love it. It seems that everyone wants to know how many steps are taken from one corner to another. But for certain ants, it’s much more than that. It’s your personal GPS. Ants, guided by an internal pedometer, live in the hottest desert on earth.
Follow the path
How are ants normally guided? Some of them are based on the fact that they mark the path with pheromones. Then they go back this way, like Hansel and Gretel. Others are fixed in the event of certain accidents in the terrain in which they are moving.
The ants that live in the Sahara (Cataglyphis fortis) Do not use any of these methods. However, large areas of land can be moved without a reference point. They fascinate biologists for many reasons. One of them is that they hold the title of the fastest ant in the world. You can travel at a speed of 3.6 km / h.
They spend the first four weeks of life in the darkness of the underground shelter. There they look after the queen and her young, build chambers, dig and clean the anthill tunnels.
After that time, they leave the detention center and go outside. How to calibrate your GPS complex. During a reasonable amount of time, they take small exploratory walks around the anthill. There they support temperatures of up to 53 ° C. And they make random curves that allow them to look at the anthill every few meters.
Test the theory
The ants, which are guided by an internal pedometer, thus adjust their internal compass. You can now search for food. His return is always a straight line towards the anthill, without detours. How do you do that? In a simple and fascinating way. During the outward journey, they successively recorded the different directions they had taken. The distance too. You know the length of your stride and perform a math calculation based on inferences.
It’s a good theory. How do I test it? It was carried out by a group of German-Helvetic scientists under the direction of the German Matthias Wittlinger. He made micro-holes for ants to attach to the insect’s legs. They lengthened their stride. Another group had mutilated their legs an inch to take shorter strides.
The scientists drove the ants away from the anthill and manipulated their legs there. Without exception, all ants have missed their location. The waders passed and the short-legged ones didn’t reach the anthill. It was concluded that the key factor in returning home to these Hymenopterans was the length of the stride. That is, your internal pedometer.
Their wonderful GPS allows them a little more. Add an additional variable for horizontal projection. In the sandy area you can calculate the small valleys and hills that are on your way.
Now you can see on your networks the number of steps you took today. It would be good if this had some other use … but these are the times we live in.