I get news alerts every day all day about a variety of headlines pertaining to anthropology, science, culture and, specifically, skeletal remains. The other day, my friend was watching one of those ‘CSI’, ‘Bones’ types of shows and commented, “there can’t be this many cases that they’re solving! Where are they finding all those bones!?”
That’s a good question! One thing to keep in mind is that these TV shows often conflate and merge multiple positions and responsibilities into a single character. So, teams may be much bigger or duties may be outsourced to another lab. One team may not be solving ALL the cases in a given area. However, skeletal remains are found and reported quite often.
Some skeletal remains may be moved by flowing waters or heavy rains, unearthed from erosion or construction, moved and ravaged by predators, etc. When I was in field school, because the area was on a hill, it was not uncommon to find a skull that had rolled away from its body, or some finger bones in the sediment of the gravel path below.
For a person just enjoying the weather, it can be unnerving to be on a nice mountain hike and suddenly see a mound of bones. Some bones can be pretty easily identified as animal (non-human) based on talons, claws, animal shaped skulls or the presence of fur. But it’s not always easy.
So, as the protocol goes- a jogger sees bones, calls the police, the police take a look, confirms it’s skeletal, they call their forensic anthro or osteologist and that person says, “Is it human? Send me a pic.” They snap a pic and text it to the expert and the person either says, “It’s a bear” or “I’m on my way.”
(Please note I simplified for the sake of time).
While some law enforcement teams are trained to be able to make these distinctions, it can become difficult when only fragments are present or bones have been destroyed by the elements of outdoors and predation.
Take a look at that mummified bear claw again. Mistaking this for a human hand is a reasonable mistake. Even next to the human x-ray, it takes a bit of analysis and training to be able to see the differences on site.
Forensic anthropologists and osteologists train so that they can identify fragments, and even then it can be impossible. They spend time understanding comparative anatomy (human vs. orangutan; cat vs. dog; bear vs. NBA player, etc).
Additionally, non-human animals are an important part of human history, so anthros find it necessary to make them part of research. The identification of non-human remains is a big component of archaeological and historical research. Zooarchaeology is the study of animal remains from archaeological sites, to understand all aspects of past human-animal interaction.
Before I digress too much, what are few areas that can be examined beyond claws and fangs?
The vertebral column, or spine, can be very telling! The below image shows a human (left) versus a sheep (right) spine. Looking at the examples side by side helps to immediately eyeball which is human and which is a 4-legged animal (quadruped). The sheep bones in closer to the neck are longer and more narrow that the cervical bones in the human. The middle thoracic bones on the sheep are really long and pointy. This part of the bone is known as the spinous process.
The human spinous process points down rather than out, and is much shorter than what we can see in the sheep.
This next image compares the ox caxa, or pelvis bones, of a human and a elk. Individually, they may be a bit harder to tell apart for an untrained eye- especially if broken.
The elk (left) is taller and more narrow than the human (right). If our pelvis was that tall and narrow, we wouldn’t be able to walk upright.
Also, check out that acetabulum. That’s the round area above the big hole (obturator foramen) in the pelvic bone. That’s where the thigh bone (femur) joins with the pelvis. It’s a ball-and-socket joint. The elk acetabulum is not as round or deep as the human.
Human and non-human animals share many skeletal traits, but there are lots of variability and distinctions that can help tell them apart. If you are interested in understanding human skeletal biology, I would highly recommend that you also understand it in comparison to non-humans.
Resources and citations
Sims, M.E. 2007. Comparison of Black Bear Paws to Human Hands and Feet. Identification Guides for Wildlife Law Enforcement No. 11. USFWS, National Fish and Wildlife Forensics Laboratory, Ashland, OR.
Byers, S. N. 2002. Introduction to forensic anthropology: A textbook. Boston: Allyn and Bacon.