As the tortoise scuttles off, life again returns to normal for the owl family. Once the danger has passed, the female emerges from the hole, accompanied by the only surviving chick from the eleven eggs she had laid, while the male flies off in search of nearby prey. The burrowing owls eat almost any animal which is not bigger than them. If you hope to survive in this harsh environment you can’t afford to be a choosy eater, and these small birds of prey happily devour anything from insects and amphibians to squirrels and lizards. On this occasion it is a mouse that has fallen into his claws. The male breaks its neck with his beak, and then carries it back to the hole, where the female tears it apart and prepares it. But the chick, which has already developed feathers, becomes impatient, and decides to take the largest part of the booty into the safety of the nest to devour it in peace. The burrowing owls rarely dig their own holes. Generally, they use the tunnels made by another inhabitant of these wide plains, an ancient animal which in the early morning retires underground. The nine-band armadillo is one of the descendents of a race of armour-plated creatures that have lived on earth for millions of years, with virtually no physiological changes. The armour from which their name comes protects them against enemies and allows them to make their way through the undergrowth. But it presents a distinct disadvantage during the hot hours on the plains. The leathery surface of its dark scales rapidly absorbs heat. When the sun comes out and temperatures rise, the armadillo’s protective shields cause it to overheat, and it has to seek cover underground. And this curious survivor of former ages not only does this rapidly and efficiently, but what’s more, digs its burrows at the base of the termite mounds that are scattered across the plains, an impressive adaptive strategy. These structures offer the armadillo two great advantages. On the one hand, they have a sophisticated ventilation system and, on the other hand, they are full of termites. The lodger thus has an air-conditioned room and a larder full of food. For our tortoise, the sun becomes increasingly unbearable. Its reptile physiology will help it to bear the heat, but she is disorientated in this dry, suffocating world. Finally, a breeze carries across the smell of water, and indicates which way she should proceed. And slowly, patiently she enters the lowlands where the water left behind after the rains still feeds the last patches of green on the plain. Swamps and low-lying areas still hold water until well into the dry season. The soil of the plains is thick clay, and this is the essential factor making such incredible biodiversity possible in a place where conditions are so harsh. Because the clay prevents the water from draining away, and so pools form. For the animals of the plains, the flooded areas provide relief from the intense heat. While the burning sun paralyses life on the grasslands, the fauna of the plains gathers here in search of food and water. During the day, thousands of birds come here to feed. Under the shallow waters of the flood areas swim innumerable fish. As the dry season advances, the patches of water become increasingly smaller and the fish progressively concentrate, making them easier to catch. And so, the pool is crowded with fishers. The American ibises search the cloudy waters for small fish. They move their extraordinarily specialised beaks from side to side until they find their prey, fish of between three and five centimetres in length. If they touch weeds, branches or fish of different sizes they calmly continue their search. But if the beak brushes up against one of the fish they are looking for, it will clamp shut with amazing speed, trapping the victim in twenty-five thousandths of a second one of the fastest reactions of any vertebrate in the world. Scarlet ibises, spoonbills, ducks and egrets, American ibises each one uses a different technique, hunts different prey and has a different shaped tool, the beak. It is a mass gathering of specialists with jaws adapted to a specific type of prey, and so reducing competition among species. From up in the air, too, there is a beak that can skim the water in search of fish close to the surface, and that beak belongs to the scissorbill. Like the ibises, the scissorbills are selective and only close their beaks if they touch a fish of the right size. Even so, it is a risky fishing technique because on occasions the obstacles they come across turn out to be spectacled caimans.