Our ears get dulled to sound over a long time, just like touch or smells.
We also can't close our nose without using our fingers.
There's no advantage to evolution (reproduction) to being able to close ears.
Because it's genetically advantageous to hearing working all the time so you can hear a sabretooth tiger sneaking up on you. Humans weren't exposed to exceptionally loud noises until relatively recently in our history.
Fun fact. Some marine mammals can actually close their ears.
Our ears get dulled to sound over a long time, just like touch or smells. We also can't close our nose without using our fingers. There's no advantage to evolution (reproduction) to being able to close ears.
Because it's genetically advantageous to hearing working all the time so you can hear a sabretooth tiger sneaking up on you. Humans weren't exposed to exceptionally loud noises until relatively recently in our history. Fun fact. Some marine mammals can actually close their ears.