��� Dinosaurs Doomed Before the Asteroid? | Owensville High School Newspaper | iHigh.com









Gym Calendars



Home » Newspaper News

Dinosaurs Doomed Before the Asteroid?

January 17, 2013
Owensville High School

Dinosaurs Doomed Before the Asteroid?

Brittni Cebulak

We are all familiar with the theory of the giant asteroid that made the dinosaurs go extinct, but would it surprise you to know that some species of dinosaurs may have been doomed before this terminating event?

A new study has shown that large-bodied herbivores, like the triceratops, “were in slow decline before being totally wiped out 65 million years ago.”

"Did sudden volcanic eruptions or an asteroid impact strike down dinosaurs during their prime? We found that it was probably much more complex than that, and maybe not the sudden catastrophe that is often portrayed," said lead author Steve Brusatte, a Columbia University graduate student affiliated with the Museum of Natural History.

Researchers observed the changes in biodiversity within different dinosaur groups over time to piece together pictures of the creatures’ well-being. An increase in one group’s “variability could indicate that it was evolving into more species, improving its chances of survival.” Conversely, a “decrease in variability could be the first warning signs of extinction in the long term.”

The study found that duck-bill hadrosaurs and horned and frilled ceratopsids may have experienced a decline in biodiversity over the last 12 million years of the Cretaceous period. Still, hadrosaurs only seemed to be declining in North America, while they increased in biodiversity in Asia, which complicates the findings.

Other groups of dinosaurs remained “reltively stable or even slightly increased in biodiversity, including the heavily armored ankylosaurs, the fearsome T-rex, and enormous herbivores like the long-necked sauropods.

“Contrary to how things are often perceived, the Late Cretaceous wasn't a static 'lost world' that was violently interrupted by an asteroid impact," Brusatte said. "Some dinosaurs were undergoing dramatic changes during this time, and the large herbivores seem to have been mired in a long-term decline, at least in North America."

Source: http://www.foxnews.com/scitech/2012/05/01/some-dinosaurs-doomed-before-asteroid-strike-study-says/


Tags Owensville High School • Publisher
Rate This Article
Thanks for rating this article!
Share This Article