If you ever stumble upon bones - and you're not an anthropologist, a veterinarian, or an archaeologist - it may be difficult to know if the remains you're looking at belong to an animal or to a human. While certain bones, such as bird bones, are easier to identify, some animal skeletons resemble those of humans. Scientists use animal bones as stand-ins for human bones in experiments. Fortunately, there are many ways to determine whether your yard is a crime scene, an archaeological jackpot, or the site of an animal graveyard.
Please note you should always report any questionable bones to the police to rule out the possibility of human remains.
Animals Don't Really Have Chins
You can rule out many skulls as human, based on their elongated shape, the size, or the placement of the eye sockets. Another clue to a skull's origin is the presence or absence of a chin. The chin "is not seen in any other hominid species."
One theory speculates we need a chin to help us chew our food, but researchers are divided on whether that's true. Another idea is the chin assists in speech, though there is no solid evidence of this, either. Chins may have evolved by sexual selection. However, both men and women possess the trait.
Pigs Have Leg Bones Similar To People's
Pig bones are commonly used in experiments as stand-ins for human knee and leg bones. However, size differentiates human and swine knees. For instance, pig femurs are shorter than human femurs but larger in circumference.
Professionals can distinguish a pig leg bone from that of a human by measuring it, checking its density, and comparing it to a known sample. The mineral content in pig bones is much higher than in humans bones, which a trained professional can test and identify.
Teeth Can Offer Clues To Diet And Species
There Are Key Differences Between Human And Primate Bones
Although humans and primates are closely related, there are many differences between the skeletal structures of the two that can help with identification. Primates have longer forearms that allow them to walk on all of their limbs. Monkeys have narrow hips and a flatter pelvis, while humans have wide hips and a curved pelvis.
Human rib cages are smaller than primates, and the spine is curved. A human foot will have an arch, whereas animal feet are flat.
If The Bones Are Hollow, They're Suited For Flight
Bird bones may be the easiest to distinguish from human remains. They are generally smaller and usually accompanied by additional bones not found in human anatomy. One clear giveaway is that bird bones are hollow.
They have empty spaces for air sacs, which supply extra oxygen for flight.
Turtle Shells Can Mimic Human Skull Pieces
Turtle shells are made up of overlapping layers of keratin that form outward from the animal's ribs and spine. When the shell is left to bleach in the sun, whether in pieces or intact, it's sometimes mistaken for a human skull.
Rudy Nunez and his 5-year-old son were walking on a riverbank in Oklahoma in May 2016 when they stumbled upon a bone. Nunez's son thought it was from a turtle shell, but authorities recognized it as a human skull fragment.
Human skull bones have "spongy-looking cancellous bone" on the inside, and the turtle shell does not.