What happens when a snake sheds its skin?

You wanted to know

"What happens to the discarded skin when a snake sheds it?" asked a young Fremont Library patron in Mundelein who attended a youth program.

Almost the entire planet is covered in snakes.

The 3,400 species that slither across the earth and through the seas range in size from a few inches to more than 20 feet.

Snakes are key players in the web of life, as they keep rodent and insect numbers down.

Snakes have some unusual traits. Did you know its split tongue helps it to smell out prey? Snakes use their nostrils and a unique sensory system, called a Jacobson's organ, that analyzes chemicals collected on its tongue to learn about nearby prey and predators.

Here in Illinois, there are 39 species of the legless, earless and eyelid-less reptiles.

The scientific term for snake skin shedding is called ecdysis, or molting. Basically, the entire skin covering sheds almost in one piece and is turned inside-out when the process is complete.

"When a snake is actively growing, or if they're very old and shrinking, it sheds its skin," explained Andy Snider, Brookfield Zoo curator of herpetology and aquatics.

"It could shed six or seven times in the first year, and then the process slows down. Later in life, when it's not growing so much, it might shed one time a year or less."

When snakes prepare to shed, a milky-blue substance is secreted between the old and new layers of skin. The top layer becomes dry, faded and drab. Snakes speed up the shedding process by rubbing around the sides of their mouths and head, Snider said.

"The skin comes up over the top of the head and they wiggle out of it," he said.

At the zoo, snake skins found in good condition are used in outreach and education programs after they've been disinfected.

"In the wild they disintegrate fairly quickly because of the elements," Snider said. "There's really not a lot to it."

Snider is an expert on the Armenian viper, a snake species found in the Republic of Armenia, bordered by Turkey and Iran, as well as other snake species. His research has brought him to the mountainous country five times.

Find out more about zoo animals at Brookfield Zoo's classes and behind-the-scenes adventures, or visit the zoo, open 365 days a year. Admission fees are waived for all military personnel with identification.

Check it out

The Fremont Public Library District in Mundelein suggests these book titles on snakes:

• "Slithery Snakes" by Roxie Munro

• "Everything You Need to Know about Snakes" by John Woodward

• "Top 10 Snakes" by Jay Dale

• "A Snake's Life" by Ellen Lawrence