Homo erectus and Neandertals were more or less human-sized. That may not be saying much, since we are so variable in stature ourselves.
In this case, the fossils don't entirely speak for themselves. To estimate the sizes of ancient people, working with long bones, we must apply some kind of regression or other estimation method.
- KNM-ER 1481 is a complete femur from Koobi Fora, Kenya, approximately 1.9 million years old. Without any associated skull or teeth, we can't be sure what species it represents. Many scientists attribute it to early Homo because of its differences from known australopithecine femora.
- The Trinil femur was found by Eugene Dubois in 1892 as he excavated fossil beds at Trinil, Java. He had found a human skullcap the year before, and after finding the femur's humanlike anatomy, Dubois named a new species, Pithecanthropus erectus. This is the original Homo erectus femur. Today, we are less certain about its age and association with the partial skull. It may be a million years old, but it may be substantially younger.
- The femur from Spy, Belgium, represents a Neandertal who lived around 45,000 years ago. This femur is part of a more complete skeleton, and exhibits many of the characteristic features of Neandertal long bones, including the great thickness and curvature of the shaft and very large joint surfaces.
- Determine the sex of the individual. The femur head diameter is a relatively good indicator of sex. If it is less than 44 mm, the individual is likely to be a female. More than 46 mm, and the individual is likely to be a male. In between these values, you may need more information — either from the rest of the skeleton or from the size and robusticity of the femur itself.
- Measure the maximum length of the femur. This measurement is taken using the osteometric board, and represents the maximum distance from any points on the proximal and distal ends of the bone. Take your measurement in centimeters.
- Apply the correct regression equation. These are specific to sex and race. The femora at this station come from donated anatomy collections from the early 20th century, and represent people of European ancestry. The male and female regression equations for this population are listed at right.
What to do: Here you will examine the fossil cast femora, using regression equations to predict stature of the individual.
- What are some weaknesses of estimating body size for fossil humans by applying a regression drawn from a contemporary human population?