Grief is usually thought of as a human emotion– the deep sadness we feel when we lose someone we care about. But animals can feel it too. Many species show signs of mourning and emotional pain.

Amelia Thomas connected with creatures great and small for her new book What Sheep Think About the Weather: How to Listen to ...

Recent studies on red-footed tortoises prove that they're not only emotional, but can have long-lasting mood changes.