A tyrannosaur tooth embedded in a hadrosaur skull

An extraordinary fossil find provides fresh evidence about dinosaur behavior and predator-prey interactions.
Plus hadrosaurs breaking their tails while mating, a diplodocoid with a broken tail tip, and many more paleopathologies.
For links to every news story, all of the details we shared about Koparion, and our fun fact check out iknowdino.com/Koparion-Episode-565
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Dinosaur of the day Koparion, a small troodontid we only know from a tooth.
In dinosaur news this week:
• There’s a new herrerasaur, Ptychotherates bucculentus
• Hadrosaurs may have injured their tails while mating
• A Barosaurus with a long whip-like tail had a fracture at the tip of its tail
• A tyrannosaur lost the tip of its tooth in the skull of an Edmontosaurus
• A Plateosaurus with a bone infection in its right arm is the oldest known dinosaur bone infection
• Cancer has been around for millions of years, including in dinosaurs
• A few titanosaurs were found with cysts in their tails
• A mamenchisaurid sauropod had a tumor on its shoulder and arm

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