The fossilized remains of a truly ancient dinosaur have been discovered in the north-Mexican state of Coahuila. Remarkably preserved for their estimated age of 72 million years, the 50 vertebrae that were dug up once formed the basis for a 15-foot tail that was attached to a 40-foot dinosaur. Although the researchers from Mexico's National Institute for Anthropology and History aren't yet certain of the species of dino involved, their early findings suggest it might have been a hadrosaur, also known as a duck-billed dinosaur.

This is the first discovery of its kind in Mexico, though the hard work of pinpointing the dinosaur tail's location was already done for the scientists by Coahuila locals. They alerted the archeologists back in June of last year and 20 days of diligent investigative work this summer produced the fully intact fossil. Now comes the hard work of studying the details of this massive tail and attempting to learn more about the era it came from.

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