It should be possible to tell by the plants and animals whether a given area within the markers has become safe.

Other environmental hazards include the risk of attack by animals.

Tool use may also be involved in building structures by animals.

Mail delivery by animals has been used in many countries throughout history.

The plant is poisonous if consumed by people or animals.

Would a death by exposure or animals be better?

This can lead to their exploitation by humans or other animals.

The disease is spread from one region to another by sick animals.

Yes, he said, and you would mean by animals living beings?

This fountain was used for drinking by men and animals alike.