Do you know any adults who have wrinkles in their skin? A word to the wise: don't ask them about their wrinkles. Just absorb today's Wonder of the Day and pretend you've never seen their wrinkles! You can thank us later…

To understand where wrinkles come from, we must first know a little bit more about the skin. Did you realize that your skin is an organ? It's true! In fact, it's your body's largest organ.

And it's an important organ. It keeps your insides from falling out! It also keeps you warm in winter and helps you cool off in summer. It protects you from infections and helps you feel the world around you.

Skin is made up of three layers. The outer layer—the part of your skin that everyone can see—is called the epidermis. Underneath the epidermis is a middle layer called the dermis. Below the dermis is the innermost layer, called the subcutaneous (hypodermis) layer.

When you're young, your skin is still like new. It holds moisture and stretches easily. The dermis contains plenty of elastic fibers called elastin, as well as a protein called collagen. Elastin and collagen help your skin look and feel young and wrinkle-free.

As you get older, however, the dermis slowly loses collagen and elastin. The fatty subcutaneous layer also loses fat over time. When these things happen, your skin gets thinner and less moisture gets to the epidermis. The epidermis will begin to sag in areas, creating wrinkles.

Getting wrinkles is a perfectly normal part of the aging process. Some people get more wrinkles than others. Wrinkles are an inevitable part of aging. Even if you take good care of your skin, you're still going to get wrinkles sooner or later.

There's no certain time when wrinkles start to appear, though. Some people get wrinkles earlier than others. In fact, young people who spend too much time in the sun might develop wrinkles around their eyes — called “crow's feet" — as early as their 20s.

There's no need to worry about getting wrinkles, though. They're just a part of life. In fact, some people choose to embrace their wrinkles. When asked about their wrinkles, some grandparents will tell you that there's a story behind every one of them. What stories will your wrinkles tell one day?

Wonder What's Next?

Tomorrow, Wonderopolis takes a look at everyday people thrust into extraordinary situations.