Fourteen Fifteen

For Saturday:

Birds don't urinate.

For Sunday:

Poop is brown because of iron and a substance called bilirubin that is created by the breakdown of red blood cells and ends up in the intestine. I always kind of just thought it was brown because it was a mash-up of all the different colors of stuff you'd eaten. Now I know better.

Hopefully Monday will return us to a non-toilet-related Thing I've Learned.