When the Beavers an extinction is affecting other animals they will make other animals lack food until he could make the animals die and will result in a balanced ecosystem.
The beaver caused the extinction will affect other animals with other animals because of lack of food. It can cause animals to die and will result in ecological imbalance.
When the animal's extinction will affect the other animals, because it will make other animal food. That may make the animals die and will result in the ecology balance.