Is it human?

It's not uncommon for a hiker to find a bone in the woods. Sometimes it’s clearly from an animal, a minute mouse skull or perhaps a fragment of turtle shell. Other times, however, the origins are more unsettling: the bone may be large or perhaps unsettlingly familiar. In these cases, questions about its source may creep into mind since the words “a hiker’s chance discovery” are all too well known by Americans today. Bones of this nature are often presented to police departments for identification, but the police do not always have the necessary expertise to make a definitive identification. Instead, they might refer bones to a local coroner, medical doctor or osteologist for a more exacting opinion.

That said, there are relatively few species of animal in the Eastern United States with skeletal elements large enough to be confused with those of an adult human. Of these, many are either uncommon or have limited ranges, such as elk, moose or harbor seals. In the east, only two frequently encountered wild mammals are of sufficient size to be confused with humans: white-tailed deer and black bears. Black bears in particular are notorious among anatomists for the similarity of some of their skeletal elements with those of humans. Below is an image of a severed bear foot that was sent to my mentor at Penn State, Dr. George Milner. The construction worker who found it was deeply disturbed, thinking it to be the foot of a murdered child.

Similarly, a bear’s front paws can also look frightfully human. The image below was taken from my thesis, a photographic guide that deals with the problems of identification. At first glance, the picture seems to be that of a human hand. Closer examination reveals some differences though. For example, when observed more closely, the paw seems to have five fingers and a thumb. This “thumb” is actually an elongated wrist bone however, and not a digit.