Science!

 "During the late Cretaceous, western North America experienced several regressive and transgressive cycles of the Western Interior Seaway, which allowed dinosaur clades such as tyrannosaurids, ceratopsids, hadrosaurids and pachycephalosaurids to evolve due to habitat area fluctuations related to sea level change."

Why do I have the feeling the reporter just copied and pasted from the press release without actually understanding what the sentence means?

https://www.yahoo.com/news/articles/species-dome-headed-dinosaur-discovered-192348595.html

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