Topic
Skin
5 articles
Biology
Why do we have fingerprints?
Everybody knows they are there to help you grip. Somebody finally measured it in 2009, and discovered that ridged fingers grip smooth surfaces worse than smooth ones would. So the pattern is doing something else entirely.
Biology
Why does a mosquito bite itch?
The bite itself is so gentle you sleep through it. Twenty minutes later there is a hot pink lump that will not leave you alone for two days. Almost none of that damage was done by the mosquito.
Biology
Why do your fingers wrinkle in the bath?
Stay in the water long enough and your fingertips fold up like a plum left in the sun, while the back of your hand stays perfectly flat. Same bath, same skin, same half hour. So what decides?
Biology
Why does a bruise turn purple, then green, then yellow?
You knock your shin, nothing bleeds, and days later a mark appears and works through three colors in a fixed order. Nothing else on your body behaves like that. So what is happening underneath?
Physics
How does sunscreen stop a sunburn?
Rub it in and you can still see your skin, still feel the sun, still get warm. Nothing looks blocked at all. So what has that invisible film actually done?