Snap taken by Brian Switek
Title: The Travels of Dinosaur Teeth: Unraveling the Mysteries of Jurassic Transport
Last summer, while hanging out with paleo-pro Joe Peterson and his crew at the Cleveland-Lloyd Dinosaur Quarry, I stumbled upon a toothy souvenir - a fossilized Camptosaurus tooth. Once part of a beaky herbivore's chompers, now just an isolated crown, it had drifted away from the jaw some 150 million years ago. Whether it fell out while munching or posthumously, the tooth had a journey.
Solving the riddle of its separation may remain a mystery, but the unique nature of the Jurassic site, Utah's eastern quarry, hints at a nomadic past for the tooth. Initially seen as a swampy death trap for numerous Allosaurus and other dinos, new studies of the site's geology suggest that these carcasses were pushed together by floodwaters after their demise. This discover, surprisingly, intensifies the puzzle surrounding the abundance of Allosaurus at this spot. The Camptosaurus tooth is merely a piece of a larger puzzle - a cluster of skeletal fragments that had flowed together during the Jurassic wet season, ending the regular droughts that plagued the ancient floodplains.
A single tooth's tale may seem unimpressive, but the story of fossil preservation is pertinent to recovering life from the past. Bonebeds such as Cleveland-Lloyd, along with microsites teeming with teeth and tiny fossilized goods, are sometimes used to gauge the inhabitants of an environment at a specific time or the demographics of prehistoric species. At dinosaur bonebeds, teeth left behind by carnivores serve as proof of scavenging. A study by Peterson, Coenen, and Noto, however, reminds us not to assume the locality of fossil discoveries.
To simulate the travels of Jurassic remains, Peterson and his team tested dinosaur tooth casts in a flume. They placed high-density urethane resin casts of an Allosaurus tooth and Camarasaurus tooth - with and without roots - in a small flume to observe how they'd be swept away by water. All the teeth moved, with most traveling between five and twelve inches. The un-rooted Camarasaurus tooth, however, took the distance crown at about three feet.
These modest distances may seem insignificant, but the test aimed to understand how tooth shape and root structure impact travel. Different teeth, like the blade-like teeth common in carnivorous dinosaurs, may travel farther due to their laterally compressed shape. Teeth with roots, being denser and heavier, might not move as far. This finding, Peterson et al., argue, will alter how paleontologists interpret isolated teeth in studying prehistoric animals.
Matt Bonnan, a paleontologist, made a relevant point in response to a sauropod migration study based on the evidence gleaned from Camarasaurus teeth. Before we can accurately resurrect dinosaurs in our minds, we must first understand them in death.
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Key Insights
- Dinosaur tooth shapes and root structures significantly impact their transport distances.
- Cone-like, robust, and rooted teeth may settle near their origins, while blade-like, light, and rootless teeth might travel further.
- Understanding tooth transport allows paleontologists to distinguish between in-situ and transported fossil assemblages, essential for accurate depositional environment reconstruction and paleoecological studies.
References:
Peterson, J., Coenen, J., Noto, C. 2014. Fluvial transport potential of shed and root-bearing dinosaur teeth from the late Jurassic Morrison Formation. PeerJ. 2:e347 http://dx.doi.org/10.7717/peerj.347
- The study by Peterson, Coenen, and Noto revealed that the shape and root structure of dinosaur teeth play a crucial role in their travel distances.
- Toothed remnants like the blade-like teeth common in carnivorous dinosaurs might travel further, thanks to their laterally compressed form, while robust, conical, and rooted teeth may settle near their origins.
- By comprehending tooth transport, paleontologists can distinguish between in-situ and transported fossil assemblages, aiding in accurate reconstruction of depositional environments and furthering paleoecological studies.
- Matt Bonnan, a paleontologist, emphasized that before envisioning dinosaurs in their natural habitats, scientists must first understand them in their deaths, shedding light on migration patterns and species interactions.
