How to use the word coexistence in a sentence?

"It is amazing that a dog and a cat can live in coexistence peacefully."

Coexist is usually used when you are referring to two things that wouldn't see normally being together. It also implies in the positive (as in the example above) indifference or passivity with regards to the other item.

It can also be used in the negative with two things that normally would have a relationship with each other, and, because of something gone wrong, they live together, but don't interact or communicate.

In the neutral it can be used:

"The coexistence of two distinct tribes, directly next to each other, proves that relations between the two were amicable for long periods of time."