There are many different types of animals that shed their skin. In some animals, this is an extraordinary process where they shed their entire skin or exoskeleton at one time. These animals must shed to grow, with their bodies outgrowing their old skin or shell. The process, called ecdysis, takes anywhere from a couple of hours to several weeks, depending on the size, age, and type of animal.
Shedding not only allows the animal to grow, but it also removes potentially harmful external parasites and, in many animals, allows limb regeneration. In other animals, like humans, the body sheds dead skin cells to reveal newer, healthier skin.
Animals That Shed Their Skin
Snakes, like other reptiles, shed their skin as they grow. The process happens much more frequently when young, slowing down as the snake grows through adulthood. Snakes shed four to 12 times per year. Right before the shed, the snake’s skin begins to change color and dull, their eyes become cloudy.
The old skin becomes tight, signaling to the snake it’s time to break the skin. Snakes will rub their head on something coarse, such as a rock or bark, to create a small tear in the skin.
Once cracked, the snake will begin the process of crawling out of the old skin, often hiding in a humid environment during this process. Once free from the old skin, the snake’s color is bright and vibrant. People who keep snakes or other reptiles often track the shedding processes to ensure their pet is healthy.
2. True Crabs
Crabs are invertebrates that possess a hard exoskeleton, which we refer to as their shell. Like other invertebrates, its exoskeleton is hard and inflexible. Crabs must shed their restrictive exoskeleton to grow. To reveal the new, roomier shell, crabs crack the back of the shell near the tail. As it loosens, the crab removes the old shell to reveal a soft, pliable shell below.
The crab’s shell is its primary protection against predators, making ecdysis a dangerous, yet necessary experience. Because their new shell is soft and pliable, crabs will hide under rocks, beneath the sand, or tucked into vegetation while their new shells harden. Depending on the species, their shells may take days to completely harden.
Like crabs, spiders are invertebrates with exoskeletons. The spider must molt its exoskeleton several times throughout its life in order to grow. Spiders often retreat to a protected space to molt their old skin, protecting them from other predators during the process.
Not only does molting reveal a new outer “skin,” it allows the spider to regenerate limbs (depending on the spider’s age). If a limb is regenerated during the molt, it will appear smaller and weaker than the other limbs.
It is not uncommon to find a spider’s exuvia on the web. As with snakes, humans who keep spiders as companions often refer to their molting patterns for signs of health.
Like other insects with incomplete metamorphosis, cicadas molt their nymphal stage exoskeleton to emerge as the larger, winged adults. More than 3,000 species inhabit our planet, most preferring the tropical climates throughout the world.
Cicadas are well-known throughout the world, their loud, screaming calls a mainstay of the summer in temperate climates. Their exuviae hang on vertical surfaces.
Cicadas have an interesting life cycle, with the nymphal stage lasting numerous years. Some species are in the periodical cicada group; these species have 13 or 17-year life cycles and emerge en masse in overwhelming numbers.
They spend their nymphal stage underground feeding — their strong front legs and claws adept to life underground. When it’s time to molt into their adult form, the nymphs crawl out of the ground and up vertical surfaces such as trees and fence posts.
Frogs shed their skin much like reptiles, often in one continuous piece. The shedding process may be as frequent as daily. Frogs release their shed skin through specific body movements, allowing them to wriggle out of their old skin.
Like many other wild animals that shed their skin, frogs eat the shed skin, often leaving no trace of it. Eating their skin not only gives valuable nutrients, it also prevents leaving signals that it lives in the area. A shed skin left behind alerts predators to the frog’s existence in the area.
Geckos are curious creatures with characteristics that set them apart from other lizards. The common geckos are vocal, producing numerous different sounds, including chirps and clicks. They also possess “sticky feet,” toe pads that allow them to walk on vertical surfaces and even upside down.
Geckos are found throughout the world, except in the coldest of climates. Geckos, and all other types of lizards, shed their skin as they grow. Like with other reptiles, shedding is more frequent in younger geckos.
The final nymphal molt in dragonflies is perhaps the most spectacular for the animal. The nymph will crawl out of the water onto a vertical surface, similar to the behavior of cicada nymphs. Out of the water and off the ground, the nymph’s exoskeleton will crack and the adult will emerge.
Like other insects molting into their adult form, the dragonfly’s transformation puts it at risk of predation. The tight exoskeleton of the nymph form forces the wings to be tightly folded.
After emerging from the exuvia, the dragonfly adult must wait while its four large wings unfold and harden before it can fly and pursue a mate.
Yes, even humans shed their skin, although the result isn’t as fascinating to look at as the exuviae of other animals. Our skin grows with us, unlike the harder exoskeletons of invertebrates or the restrictive skin of reptiles.
As our skin grows, older skin cells die and fall from our bodies. According to the American Academy of Dermatology Association, humans have roughly 19 million skin cells per inch of our body! We lose 30,000 to 40,000 skin cells every day.
Although you can’t see the cells with your naked eye, you’ve probably looked at your shed skin without knowing it. Your dead skin cells actually make up a large portion of the dust in your house!