1. Size and shape. The size and shape of an animal's bones can give you a good idea of what kind of animal it is. For example, a large, heavy bone is likely to come from a large animal, while a small, delicate bone is likely to come from a small animal. The shape of the bone can also give you clues about the animal's lifestyle. For example, a long, thin bone is likely to come from an animal that runs or jumps, while a short, stocky bone is likely to come from an animal that digs or climbs.
2. Bone structure. The structure of an animal's bones can also tell you a lot about the animal. For example, the presence of a marrow cavity indicates that the bone belongs to a mammal. The presence of a growth plate indicates that the bone is still growing. And the presence of a joint surface indicates that the bone articulates with another bone.
3. Bone markings. The surface of an animal's bones can also be marked with a variety of features, such as grooves, ridges, and bumps. These markings can help you to identify the bone and the animal it belongs to.
4. Bone chemistry. The chemical composition of an animal's bones can also give you clues about the animal's diet and lifestyle. For example, the presence of certain elements, such as calcium and phosphorus, indicates that the animal ate a diet rich in those elements.
By combining all of these factors, you can often tell what an animal is by its bones.