Читать книгу Mutual Aid - Pablo Servigne - Страница 17

It’s not surprising that ants and bees collaborate in a single colony (the same family). We can also easily observe migratory birds, such as pigeons or arctic terns, flying together (the same species) so as to have a better chance of escaping predators.⁴ Anyone who has ventured to walk across a colony of arctic terns is not likely to forget the ensuing series of furious dives, their sharp beaks lunging forward, punctuated by particularly explicit cries intended to scare away the intruder, most often a marauding cat or fox.

Associating in order to achieve the same goal is also common among lionesses, who need to hold onto the prey they have caught and prevent hyenas from pilfering it,⁵ and it is even seen on Antarctic ice floes when emperor penguins, while nesting, have to fight against a common enemy: the wind. These large birds huddle together to keep warm, and take turns to occupy the most uncomfortable position: on the edge of the group, facing the blizzard. This is undoubtedly a profitable strategy, because it allows them to withstand perceived temperatures that plunge as low as minus 200°C!

In starlings, the mating season is dominated by competition, as in most species. But, after singing in early spring, and until the chicks are freed so they can defend the territory necessary to meet the needs of the whole family, starlings gather in groups of thousands of individuals, which gives them a greater efficiency in foraging and makes predator attacks almost impossible.

Trees are not to be outdone. Many species connect their root networks.⁶ In the tropics, for example, trees of the genus Cecropia are pioneers: they are the first to colonize cleared, arid lands. To accomplish this arduous and thankless task, young shoots connect up in a network through their roots, thus pooling water and nutrients. This makes it possible to reuse the root network of those that die first.