THE SECOND BIRTH

The animal resurrection exists. Animals have souls. You have to protect them.
Life is stronger than anything. It adapts to all contexts to carry the message of hope. Its organization sometimes goes beyond classical patterns. The miracle happens in forty centimeters of water just to last a species for millions of years. Trichoptera, Diptera, Plecoptera, mayflies, dragonflies and many other families of aquatic insects, emerge from the liquid only to reproduce after having spent their adolescence and youth there for years. On a stone, on a blade of grass, the memory of the past, an empty coat, an ultimate moult, an exuviae, their old identity card. The witch larva, the ugly nymph transform, dress in the most beautiful adornments of love to fly in search of a sexual partner and leave in their wake the emptied sculptures of an ugly youth. The second birth is aesthetic to be vital to the species. It is absolutely necessary to please to continue the eternal journey of genes.
The chances of reproducing in the air are greater than in water: fewer predators, more ease of movement, more opportunity to meet love, better circulation of sex hormones. Nymphs of aquatic insects must quickly transform into winged insects at the water's edge to escape fish, amphibians, reptiles. Sensitive moments open to natural selection. The weakest, the slowest, the clumsy are automatically eliminated from the circuit by predators.
The flight must be immediate. In an instant, all landmarks change, you have to orient yourself in a new world while avoiding its dangers by reflex. No time to learn. Genetics have it all, the information has been coded in DNA. Winged insects instinctively orient themselves in the air to find their loving partners. Of this rebirth, only the exuvia, hollow sculpture and larval memory of an aquatic life, signs the presence of life. The void remains, life flies away, a destiny is fulfilled. The second birth sums up in a few moments the evolution from aquatic life to aerial or terrestrial life. It took millions of years of adaptation for the animals to emerge from the liquid to colonize the mainland. Aquatic insects take a few seconds to summarize this passage.
The integument of the growing insect is replaced by a new, larger one by extracting the old skin or molting during its growth and exuvia when it is transformed into a winged insect. This stage in the growth of certain animals is dependent on hormonal regulation, often guided by changes in external factors such as variations in the physico-chemical parameters of the water: pH, salinity, ionic composition, temperature, etc. or qualitative production. and quantitative in food of a river. Certain foods produced during a period induce the growth of insects and cause them, with certain substances, to contain hormonal changes. The world in the world, that of the insect which varies in the variable outside world.

Aquatic insects have a rigid exoskeleton or cuticle composed of chitin, keratin which prevents them from continuous growth. Successive moults allow growth in stages. The cuticle is renewed in the epidermis in four main stages, all guided by the hormonal system of the insect. During exuviation, the larvae or nymphs swallow air or water in large quantities to increase the pressure of the hemolymph (equivalent to blood) Their cuticle tears on the lines of least resistance (head and thorax ) letting the new larva, a nymph or a winged and adult insect pass through. The new cuticle is soft and supple. The insect remains very vulnerable at these times due to the density of its body but also by the emission of molecules in the water during the moult which are recognized by aquatic predators. Fish recognize these odors carried in the veins of water. They are stationed downstream awaiting outbreaks of aquatic insects. They can, according to hormonal odors, recognize the species of aquatic insects see their stages of life and the quality of production.
The new insect emerges while seeking refuge. He leaves behind him a permanent trace of his passage and his existence. The qualitative and quantitative presence of the stored exuviae makes it possible to study the ecotoxicity of the sediments. If a sediment is polluted, the insects disappear and their molts too. Disappearance can be selective. It helps to understand the impacts and their identification. Pollutants are transferred by contact with sediments to the skins of insects: the exuviae. By analyzing the moults, we identify the pollutants present in the sediments.
If the exuviae play a role of bio indication, they especially allow to evaluate and locate the nutritional productions of the rivers. The quality, the quantity of exuviae on a course defines its biological richness. The exuviae trace the production of insects over time. They tell the story of the river and its projection into the future while conveying information about its health and its biodiversity through the development of populations of aquatic insects. The exuvie source of nutritional information for fish and health information for humans integrates all the events taking place in a river to better understand the scenario.