Answer: only one owner
Explanation: I just did the quick check!
Explanation:
Cold springs can affect the reproduction of rabbits as the rabbit's main priority is to survive before adding more to its family as they would already be struggling to keep itself warm. Yet alone a newborn rabbit which doesn't have any fur yet.
Also, cold springs could affect the amount of food that grows so the competition for food is more harsh so more rabbits are likely to die of starvation.
Though I'm not sure what your temperature range of a cold spring is so I might be giving extreme answers.
The theory would be endosymbiont theory. It was developed on the idea that some eukaryotic organelles come from prokaryotic organisms. It is also known as symbiogenesis. This theory says that these organelles were first from prokaryotic cells that is living inside a host cell.