what opens and closes in nature?

Question

Ex. venus fly trap



thanks

Answer 1

Many flowers close at night. As do the jaws of every animal ever discovered (unless it hasn't got jaws, like the sponge).

Answer 2

Many flowers.

there used to be a "clock" in English folklore, which assigned each hour of the day to a flower either opening or closing.

"Jack go to bed at noon" is the common name for a wild flower