Misc: Which of these nuts is not actually a nut - peanut, cashew nut, macademia nut?

Questions

Rats can swim for a 1/2 mile without resting, and they can tread water for _____ days straight?

There are ______ known species of bats?

The massive skeleton of the African elephant accounts for about _______ percent of the body weight?

The crayfish isn't a fish at all - it is related to the?

There are about _____ species of owl?