This is the fourth in a series of posts reviewing last year’s stories, according to theme and topic. This one is about this year’s new species, both living and extinct.

Dinosaur bodies are often covered in odd spikes, plates and sails, but a newly discovered species called Concavenator had a uniquely bizarre structure – a hump on its back, supported by two spikes coming out of its hips. Francisco Ortega, who discovered the 6-metre-long predator thinks that the hump was a deposit of fat but it could have been used for communication or keeping cool. Concavenator’s arms also have a row of small bumps that would have acted as attachment points for feathers or, at the very least, simple rigid filaments.

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