Who invented the buzzsaw? Not humans. Sharks! This one specimen from right here in Utah is a tooth whorl that was embedded in the lower jaw of the prehistoric shark, #Helicoprion. An evolutionary master of geometry, Helicoprion could use its multiple, serrated, backwards-curving teeth like a buzzsaw; the semicircle exposed (and not embedded inside the jaw), just by its shape, caused a sawing motion to occur when the animal closed its mouth. The teeth would grow forward (moving to the right of the first photo), become smaller, and spiral inside of the jaw itself; perhaps resorption occurred inside. This is our current understanding of this amazing animal, and we haven't understood its jaw until relatively recently. Perhaps the future will alter this model! Third image from YouTube, artist sadly unknown. Fourth image by #RayTroll. #paleontology #scicomm #science #usofscience #biology #zoology #geology #fossil #fossils #elasmobranchology #nhmu #naturalhistorymuseum #naturalhistorymuseumofutah #utah #saltlakecity #shark #sharks #marinebiology (at Natural History Museum of Utah) https://www.instagram.com/p/BpyPHPZgQj-/?utm_source=ig_tumblr_share&igshid=1ras3vmibkcwx
