Little loved by many, often misunderstood, the snake It is a small silent ring between water and earth, prey and predators, different ecosystems. Still, science tells us in a much more complex and fascinating way. It is in fact a snake which, unlike the viper that has vertical pupils, has instead Round pupils. Of a variable coloring, it is not poisonousand has ultra -specific sensory structures, unique and particular, which allow it to receive information from the surrounding environment. It also plays a very precious ecological role: it eats aquatic animals, rich in polyunsaturated fatty acids and in turn being prey to birds and mammals contributes to entering these essential nutrients in the ecological cycle of other animals. Completely harmless, however it can be parasitic vector which can reach man through the ingestion of infected meat of other predators, such as wild boar.
What is the snake and how to recognize it
The term “biscia” commonly indicate some non -poisonous snakes belonging to the genre Natrix. The most widespread species in Europe, and also in Italy, is Natrix Natrixalso known as biscia from the collar or Colubro Natrice. This species is distributed in a vast area that goes from southern Scandinavia to the Middle East and North Africa.
There Natrix Natrix It is a highly specialized animal, equipped with sophisticated physiological and behavioral adaptations. The physical characteristics, also very visible that make it facceptedly distinguishable from other European snakes I am:
- a length that can exceed 120 cm (females are generally larger than males);
- two Yellow spots or orange Behind the head, in the shape of a crescent that form a sort of collar;
- big eyes with Rotonda pupil;
- Variable coloring, from green to light brown, depending on the region.
The biscia also, has a non -aggressive behavior. In case of threat, it tends rather to escape or pretend to be dead. It is found in humid habitats: banks of rivers, lakes, canals, wooded wetlands and sometimes in the gardens. I often hunt along the margins of the water, where he captures mainly amphibians like toads and frogs, with the help of the sophisticated Vomeronasal organ (also called “Jacobson’s organ” or Vno).
Bisce have an extraordinary sensory structure
Recent ultrastructural studies (analysis of the internal structure of the cells) conducted on Natrix Natrix have revealed the complexity of theVomeronasal sensory epithelium (VSE), key structure in the detection of pheromones and smells of prey and part of the vno. During embryonic development, the VSE form Mobile columns ordered Rich of stem cells, neurons and support cells. This architectural scheme, unique among reptiles, allows a continuous production of neurons (neurogenesis) and a surprising regeneration capacity.
Not only that, the Vno, in fact, is connected directly to the mouth, and receives chemical information collected by the bifurcical language of the biscia. This system makes of the Natrix Natrix An authentic specialist in the “chemical reading” of the world.
Bisce play a silent, but fundamental ecological role
The biscia is not just a predator: it is also prey and ecological carrier of essential nutrients. Studies conducted in Russia and Poland have shown that Natrix Natrix contributes to Transfer of polyunsaturated fatty acids (PUFA) from aquatic to terrestrial environments. These essential nutrients, summarized mainly by algae and aquatic microorganisms, pass to these snakes through the frogs they feed on. In turn, the snakes become food for terrestrial birds and mammals, closing the ecological circle.
Like many reptiles, biscia can also be considered a good Bioindicator of healthy environmentswhich with its presence signals us the high quality of the environment in which it is located. If the habitat degrades (for example with pesticides, channels or loss of vegetation), in fact, the populations of reptiles, and small amphibians they feed on, tend to decrease.
Sometimes it can be a tank of parasites
The biscia, however, can accommodate numerous parasites, including the Trematode Alaria wingedwhose larvae can infest wild mammals and even get to man through infected meat consumption (especially of boar). The ingestion of infected meat can cause an infection called alas whose symptoms are: lowering of pressure, intestinal inflammation, slight respiratory symptoms and in the most serious, but rare cases, anaphylactic shock.
In a recent study, out of 51 specimens analyzed, 50 were carriers of elmininti, with one prevalence of 58.8% of A. Alata. This data highlights the importance of the biscia as paratenthat is, an intermediate passage in the complex life cycle of the parasite.
