Q: Do giraffes have high blood pressure...

Q: Do giraffes have high blood pressure because of the need to pump blood all the way to their heads?

A: Not really, according to Randy Rieches, curator of mammals at the San Diego Zoo. A series of valves in the neck controls the flow of blood so that it doesn’t drain out of the head when it is elevated, or rush to the head when the animal bends over to eat or drink.

A giraffe’s blood pressure is about the same as that of an average human at its head, but is about twice as high at its feet. To compensate, veins and arteries in the legs have thick walls to prevent leakage or bursting. The giraffe’s skin and the tissue under it also fit very tightly to prevent leakage.