Finding bones raises questions about their origin. While animal bones are common, identifying potential human remains requires careful attention. Distinguishing human from animal bones is complex, often requiring expert analysis. This article guides identifying potential human bones and outlines appropriate steps, emphasizing definitive identification always rests with trained professionals.
Key Anatomical Markers
The human skeleton displays distinct characteristics due to bipedalism. This adaptation influenced bone shape and structure. The human pelvis is shorter and broader, forming a bowl-like shape supporting the upper body during upright posture. Most quadrupedal animals, in contrast, have a longer, blade-like pelvis.
The spinal column also reflects bipedalism with its characteristic S-shape, which helps absorb shock, distribute weight, and maintain balance. Human femurs (thigh bones) angle inward from the hip to the knee, positioning knees closer together and directly under the body’s center of gravity. This allows for efficient striding and upright standing.
Human skulls exhibit a large, rounded braincase relative to a smaller, flatter face, accommodating large brains. Muscle attachment sites on the human skull are less pronounced than those found on many animal skulls, which often feature crests and ridges for stronger jaw and neck muscles.
The foramen magnum, the opening at the base of the skull where the spinal cord connects, is centrally located underneath the skull in humans, aligning with upright posture. In most quadrupedal animals, this opening is positioned more towards the back.
Human long bones, such as the femur and humerus, are more gracile or slender than those of similarly sized animals, as humans do not bear weight on all four limbs. When examining a cross-section of a long bone, the outer cortical bone layer in humans is typically about one-quarter the thickness of the entire bone; in animals, it can be half.
Human bones also show a greater proportion of spongy, trabecular bone, which contributes to weight distribution and support.
Common Animal Bone Confusions
Many animal bones can be mistaken for human remains, particularly when fragmented or incomplete. Deer bones are frequently confused with human long bones and ribs; deer long bones are more robust and less curved. Their mandibles are often V-shaped and separate at the midline, unlike the U-shaped human mandible.
Skinned bear paws can resemble human hands and feet due to similar size and morphology. Skeletal differences exist.
Bear paws have distinct metacarpals and metatarsals, and their phalanges (finger/toe bones) exhibit specific ridges and deeper grooves. Bears also have five toes on each paw, each with a claw, often removed when skinned.
Pig bones, particularly teeth, are a common source of confusion due to their omnivorous diet and shared dental characteristics. Both have molars, premolars, canines, and incisors, but pigs typically have 44 teeth, more than the 32 adult human teeth. Pig molars often have a more “popped” or irregular cusp pattern.
Bones from large domestic animals like cows, especially vertebrae and large fragments, can be mistaken for human bones. Cow bones are much larger and more robust. Sun-bleached turtle shell pieces can mimic human skull fragments, though human skull bones have spongy cancellous bone inside, which turtle shells lack.
Responsible Actions Upon Discovery
If you suspect human remains, act responsibly and avoid disturbing the scene. Do not touch, move, or collect the bone or any surrounding objects, as context is crucial for forensic analysis. Moving remains compromises evidence and hinders investigations.
Immediately contact local law enforcement (police, sheriff’s department) or the medical examiner’s/coroner’s office. Provide specific location information, including GPS coordinates.
Law enforcement will assess the discovery to determine if the remains are human and whether they are recent (potentially a crime scene) or historical/archaeological. Unauthorized disturbance or collection can result in legal consequences and impede investigation.