You know, your question reminds me of a couple other science questions from curious readers. Evangeline, age 7, wants to know why her hair is black. Sureya, age 8, wants to know why some people have curly hair.
It just so happens that one of my favorite science projects explores our questions about what makes us unique. It has to do with our DNA, or the blueprint for life.
It’s usually later in life that we see the more dramatic signs of aging, like gray hair, wrinkles, and lots of birthday candles on our cake. But we really start growing older from the time we are born.
The dodo bird isn’t with us anymore, but if you visit a city park you’ll likely see one of its very close relatives walking around. It might even be nibbling on a French fry. Dodos were a pigeon, said my friend Michael Webster.
A hundred years ago, human beings only lived to be about 50 years old. Now people are living longer, so there’s more time for cancer to develop in their bodies. That’s what I learned from my friend David Liu who researches cancer at Washington State University.