We noticed this especially during the 2020 lockdown , when we were forced into the house to escape the threat of Covid : we humans are not alone in our cities . Between our balconies butterflies and insects of all kinds fly, among the streets bordering the countryside it is easy to meet foxes and wild boars in search of food and even some fallow deer or roe deer that have lost their way home. At night, bats and owls fly between the houses. As surprising as it may seem to us, each of these living things - including mosquitoes and mice! - it helps to maintain a unique ecosystem in balance that is mostly unknown to us: the city ecosystem, a real "wood" with fountains instead of ponds, pylons instead of trees, buildings to perform the function of rocks and ravines.
The biologist Marco Granata in his invisible Bestiary (Il Saggiatore, 2022, pp. 320) then leads us to discover the animals that inhabit the spaces closest to us , telling us how they have adapted to our presence: from the crows, which have learned to recognize the lights of the traffic lights to be crushed the nuts by the moving cars, to the wasps, whose female after fertilization begins by herself the construction of her own nest in the attics or in the cavities of the concrete walls, passing through the eared tortoises red, aliens who have invaded the lakes of our parks.
In short, a story , that of Marco Granata, at the same time scientific and personal and dedicated to the mysterious connections that biology weaves between the room and the roof, between the gutters and the sewers, between the suburban fields and the large squares. A story with a precise thread: the city, like the forest, is an ecosystem… rich, vital, but also fragile and to be preserved. It is an ecosystem with its biodiversity in delicate balance and as such to be protected like a forest or a high altitude lake. In fact, it contributes to making our world richer, which is losing plant and animal varieties at an astonishing rate due to human action, especially pollution.
With his stories of “urban animality”, Granata tries to remind us that the greater the biodiversity, the greater the ability of ecosystems to withstand pressures and changes coming from outside. The smaller the variety of animal and plant species, the greater the weakness of the planet Earth.