Scylla Posted July 13, 2011 Share Posted July 13, 2011 About the last known dino fossil... http://news.sciencemag.org/sciencenow/2011/07/case-closed-for-dino-killer.html?ref=hp Link to comment Share on other sites More sharing options...
Auspex Posted July 13, 2011 Share Posted July 13, 2011 Love it! I hoped that a concerted effort and a little luck would fill the gap and chip away at the "extinct long before the impact" arguments. This doesn't settle the mechanism of the extinction, but it's a step. "There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant “Try to learn something about everything and everything about something.” - Thomas Henry Huxley >Paleontology is an evolving science. >May your wonders never cease! Link to comment Share on other sites More sharing options...
siteseer Posted July 18, 2011 Share Posted July 18, 2011 I can understand why some paleontologists are unimpressed by the find of a broken ceratopsian horn high in the Hell Creek. Dinosaur teeth have been found above the K/T boundary but have been quickly dismissed as reworked material from the Hell Creek even when they show no sign of transport. I can accept that since they are found in river deposits and teeth can take some transport before fragmenting that the fossils were probably reworked. Paleontologists argue that the finding of a dinosaur skeleton in Early Paleocene rocks would be evidence of the group surviving past the K/T boundary. With that in mind a broken dinosaur horn is not necessarily evidence of dinosaurs that high in the Hell Creek. In fact, it is a more obvious candidate of a reworked fossil than a complete tooth crown because of its damage. Perhaps the Biology Letters article offers evidence eliminating the chance that the specimen was washed out of an older bed and came to rest again in younger sediments. Let's assume the horn section was not reworked and represents a Triceratops living within thousands of years of the impact. One piece of horn not only testifies to the presence of an individual but also to other individuals living during its lifetime. It had parents and likely fellow hatchlings and possibly other members in its family group or herd so we could say there were some Triceratops living at that time. However, we also have to recognize the indication that there were fewer of them than during the time represented lower in the Hell Creek where remains of that dinosaur are common and more substantial (skulls and skeletons). I think more dinosaur fossils will be found at that level and probably higher but even ten or twenty more bone pieces (or even a skeleton or two) won't be strong evidence of a healthy dinosaur population right up to the boundary especially if a high percentage turn out to be Triceratops as well. One genus (particularly one represented by a single species as in the case of Triceratops) dominating a fauna is clear evidence that something was already going wrong for dinosaurs a few million years before the impact. About the last known dino fossil... http://news.sciencemag.org/sciencenow/2011/07/case-closed-for-dino-killer.html?ref=hp Link to comment Share on other sites More sharing options...
Kosmoceras Posted July 22, 2011 Share Posted July 22, 2011 Wow! I love that article! Thanks for the link to it! Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now