Molting in snakes
What is molting
Molt (General definition) – the process of change of the integuments of animals having diverse nature.
Among invertebrates typical molt occurs in nematodes, kolovorotny, arthropods and similar groups. Most of these animals is regulated by the molting hormone ecdysone 1. Given that molecular phylogenetics of these groups related to each other, the last time United under the name Ecdysosoa – Moulting. These groups molt is limited to periodic flushing and replacement of cuticle. Before the molt, the inner layers of the old cuticle dissolved, and under it the cells of the hypodermis secrete a new cuticle. After molting, the animal rapidly increases in size (usually by absorption of water or “blowing” air) before hardening of the new cuticle, after which the growth stops until the next molt (periodic growth).
The nematodes molt larvae (usually there are four larval stage), adult nematodes do not grow and do not shed. Most groups of arthropods (crustaceans, spiders, etc.) molting and growth continues throughout life.
Molting in insects, as a rule, multi-stage larvae; in insects with complete metamorphosis during the last moult the larva turns into a pupa, and after the flushing of the skin of the pupa, the insect transforms into an adult form — adults. In insects with incomplete metamorphosis during the last moult the larva turns into an adult (mayflies have a winged stage subimago, which before transformation into the adult insect molts one more time. The adult insects do not grow and do not shed.
Among vertebrate molting occurs in all tetrapods. Molt, shedding several layers of keratinized epithelial cells, frogs and toads. Molt also characteristic for representatives of reptiles. Among reptiles snakes periodically shed their entire horn cover, this forms a so-called “Nightcrawler” – discarded “skin” of the snake. Birds when moulting plumage is replaced, and in temperate and polar latitudes there is seasonal shedding (spring and autumn) – winter change of plumage in summer. Sometimes this changes its color (snowy owl, ptarmigan). In mammals living in temperate latitudes, as a rule, molt also takes place twice a year – in spring, when reset a thick winter coat, and fall, when growing a warm winter cover. Often changes and the color of this cover, for example, from birds, squirrels, etc.
1 Ecdysone (from the Greek. ékdysis — molt) is a hormone belonging to the group of steroids (27 to 28 carbon atoms) that stimulates moulting and metamorphosis of arthropods.
Molting in snakes
Normal molting is a complex process in which cells of the intermediate zone of the epidermis (the outer few layers of living cells beneath stratum corneum) proliferate and form a new corneal layer, called inner epidermal generation. Roughly speaking this is a biological process during which reptiles have formed a new cover and reset the old one.
Reptiles, in particular snakes, quite a long time preparing to “change the skin”, worry, lose appetite. Time before moulting, the herpetologists call a period of “blue eyes”. Snake skin looks lifeless, dull, fade, drawing on it loses clarity, and her eyes become filmy blue. The behavior of animals during this period also varies: some are sluggish and don’t move at all, others are nervous and exhibit increased aggressiveness. Poisonous snakes are especially dangerous: accidentally disturbed, they can actively attack and try to bite.