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Post by tetonbabydoll on Dec 20, 2008 4:48:00 GMT
Fine. I'll start this one myself.
Is there ANY evidence that any dinosaurs, or flying and marine reptiles survived the extinction? Has even a single dinosaur fossil been discovered past the KT boundary? Besides unsubstantiated rumors and bedtime stories, is there any reason to believe that some of them survived. ( aside from birds..)
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Post by sbell on Dec 20, 2008 4:56:54 GMT
Fine. I'll start this one myself. Is there ANY evidence that any dinosaurs, or flying and marine reptiles survived the extinction? Has even a single dinosaur fossil been discovered past the KT boundary? Besides unsubstantiated rumors and bedtime stories, is there any reason to believe that some of them survived. ( aside from birds..) It has been discussed in literature, but I am not aware of any material that was conclusively found post-K/T; except for materials that were moved about and redeposited (I know that we occasionally find belemnite pieces in some of our late Eocene deposits, for example, but they stand out readily because the preservation is completely wrong).
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Post by itstwentybelow on Dec 20, 2008 5:22:05 GMT
I know that there have been hadrosaur fossils discovered across the boundary and they were initially considered to be a relict population of survivors, but it was found that they had actually been shifted and redeposited by geologic processes. Champsosaurs survived until the early Miocene.
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Post by Dinotoyforum on Dec 20, 2008 10:07:29 GMT
From my plesiosaur directory:
Plesiosaur vertebrae of putative Palaeocene age were wrongly dated (Lucas and Reynolds, 1993).
Ref: Lucas, S. G. and Reynolds, R. E. 1993. Putative Palaeocene plesiosaurs from Cajon Pass, California, U. S. A. Cretaceous Research, 14, 107-111.
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Post by tetonbabydoll on Dec 20, 2008 10:58:36 GMT
So the short answer here is shaping up to be no, there is no known fossil evidence for post Kt survival. How likely is it that if the animals did survive, that none of the dead ones fossilized? I mean, we have other fossils post KT, so I would figure some fossilized evidence of surviving dinosaurs would exist? I know we don't find anywhere near them all, but still.
What kind of fossil evidence is there for directly after the KT? How much geologic time does the boundary itself represent? Are there any fossils from within it? What are the types of things found immediately after? I do not see therapods surviving without enough big game. And if the surviving plant life could not support the herbivores, then it all seems unlikely. They would not still be the same forms today anyway, would they? Evolution would have carried on? If nothing else, the plant eaters were not set up to eat grasses and modern plants, right? And they would have had to have gotten smaller? It really is a fun scenario, but I don't see how a viable population continued to survive, especially to present time. I have trouble seeing the sauropods, even medium ones, getting through the ice ages, and surviving human predation.
And, it seems pretty clear we don't have evidence of any sizable population survival post KT, even if the odd individual did for a while. I was just curious about how final the boundary really was. Guess its pretty final.
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Post by sbell on Dec 20, 2008 14:38:21 GMT
Here in Saskatchewan, we have a record at the KT directly after--there is a lot of coal and other plants fossils (petrified wood mostly), crocodiles, turtles, champsosaurs, and the earliest post-KT mammal (I believe Parectypodus). In other words, exactly what you might expect of a world that is very warm and fairly tropical. These are just the fauna I am aware of.
No dinos or marine reptiles though.
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