Пересказать текст на языке. ants have lived on earth for at least 100 million years-much longer than humans. in fact,scientists now think that the first ants must have existed about 150 million years ago.they have travelled to every corner of our planet,except antarctica.there are more than 14,000 different species and,together,they probably weight as much as the worlds population of humans! ants communicate by using chemicals called pheromones.they live in huge nests and they have developed complex social systems.each ant has a certain job to do.for example,some of them bring food to the nests,and others -soldier ants-defend it.james wilson,a biologist at bristol university,says: ”when we study ants,we learn a lot about how humans behave in groups.its fascinating! ” sometimes,animals from different species work together and help each other.an interesting example is in relationship between nile crocodile and a bird called the egyptian plover.very few animals are brave enough to go near a crocodile.its huge jaws and sharp teeth are much too dangerous.but the crocodile lets the plover walk inside its open mouth.the plover eats parasites which are bad for crocodiles.in return,it gets food and protection. like ants,crocodiles are much older than humans.scientist believe that they could have existed for 200 millions years.although dinosaurs became extinct 65 millions years ago,crocodiles managed to survive.even though they look prehistoric,their brains are more complex than many other animals.a researcher who studied australian crocodiles says they are clever animals.they can learn quite difficult tasks very quickly.but it isn’t good idea to get too close to them.they’re extremely aggressive,and several thousand people are killed by crocodiles every year.