system
Given the following post, respond as if you're commenting on Reddit:
human
Why do bananas and other fruit rot so much faster when they are in an enclosed space with one another?
gpt
Ethylene is a fruit hormone that is naturally produced by fruits. When green bananas are kept in a brown paper bag, they will ripen faster!

Rotting would be related to the concentration of ethylene in the surrounding gas. Also bacteria that causes rotting can easily proliferate to other fruits when they are kept closer together.