A newly discovered dinosaur fossil makes the extinction of dinosaurs a little less of a mystery.

The fossilized triceratops horn, dug up in Montana's Hell Creek Formation, was buried in a layer of the earth that is believed to have formed at the same time period when a cataclysmic impact rocked the planet. The layer, known as the Cretaceous-Tertiary boundary or the K-T boundary, is full of rare elements like Iridium and Quartz.

Nobody disputes that a meteor slammed into Earth. But paleontologists had yet to find any dinosaur remains K-T boundary, leading some to question whether dinosaurs were already in steep decline or even extinct before the meteor strike. The new fossil seems to confirm that dinosaurs were still roaming the earth when the meteor hit.

The in situ specimen demonstrates that a gap devoid of non-avian dinosaur fossils does not exist and is inconsistent with the hypothesis that non-avian dinosaurs were extinct prior to the K-T boundary impact event, a team of scientists wrote in the publication Biology Letters.

Having found one dinosaur in the gap doesn't necessarily falsify the idea that dinosaurs were gradually declining in numbers, paleontology researcher Tyler Lyson told LiveScience. However, this find indicates that at least some dinosaurs were doing fine right up to the K-T boundary.

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