Smithsonian.com

Photo: Bill McChesney

Maybe the bone came from the fresh soil, ready to receive spring’s bulbs. Maybe the pup brought it to the house after you let him back in. Your mind starts to race, coming up with naught but tales of murder most foul. Maybe, generations ago, a crime was committed on this very land. Or maybe it is something more mundane–the remains of the former owner’s beloved pet. Or maybe it’s just a dead raccoon.

Sorting out which story fits best demands you know what type of animal your bone belonged to. On Twitter, science writer Brian Switek pointed to an online interactive, a zoomable photo gallery of bones from a range of common creatures. A fun online portion of a larger textbook, this site of comparative osteology shows hips and shoulders and thighs and shins and more from all sorts of animals: bear, deer, dog, opossum—all helpfully showcased alongside the human equivalent (to help you rule out the murder mystery hypothesis.)

A human shoulder blade (left) and a dog shoulder blade (right), with a penny for scale. Photo: Comparative Osetology, Bradley Adams and Pam Crabtree

Intended as a field guide for forensic scientists to help police crime scene investigators figure out what is human and what isn’t, the photos are just as useful for figuring out what, exactly, the dog has got in his mouth.

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Bone-Hunter Biographies
Shrew-Eating Scientists Show Humans Can Digest Bone