Comparison of various aspects of ancient skeletons can be used to determine which species a skeleton belongs to, or if the differences are vast enough, create a new species. In later skeletons, osteometry has historically been used to attempt to identify the ethnicity or race of skeletons.
Aspects commonly studied in determining the species of very early skeletons include the length of the femur and other long bones, the capacity of the skull, the shape of the facial features and skull, the shape of the jaw and teeth, the curve of the spine, the situation and shape of the pelvis, and the location of the foramen magnum.
[1] Jaco Weinstock, 1991 https://www.sciencedirect.com/science/article/pii/S0305440399905423 ↩
[2] John E. Byrd, Carrie B. LeGarde, 2014, p. 167-191 https://www.sciencedirect.com/science/article/pii/B9780124058897000083 ↩