Cowardly Y
Any christians want to buy a dinosaur robot that your kid can buy? He can pretend he's Adam, hanging out with the dinosaurs. Yay creationism! Here's the link:
http://gizmodo.com/357119/kota-the-triceratops-is-amazing-eats-deep+fried-pleos-for-breakfast
Answer
My personal fav creationist toy was that stuffed lion that fat lady was swinging around by the tail in jesus camp, lol,
My personal fav creationist toy was that stuffed lion that fat lady was swinging around by the tail in jesus camp, lol,
Dinosaur question! About bipedal carnivores?
Infrequent
Ok so growing up as a kid, I was a huge dinosaur nut.. I had 100's of toys, I watched Jurassic Park, Walking With Dinosaurs.. Everything. I was wondering, if anybody knows the name of a bipedal carnivore that is about the size of the raptors in Jurassic Park, except velociraptors were actually much smaller than that. I know that utahraptor was about that size, but many things I have seen are pointing towards the fact that most of the medium sized pack carnivores had feathers.
So my question is.. Can somebody help me find a carnivorous dinosaur, that walked on two legs, that DID NOT HAVE FEATHERS. If no such dinosaur exist, then oh well. My life is ruined.
I hate the possibility that dinosaurs had feathers, but if the small predators looked like birds, oh well..
Is utahraptor one of the smaller theropods that is beblieved to have feathers?
Answer
There is not a single piece of evidence that any dinosaur has feathers. Some of them do exhibit "dino-fuzz." Dino-fuzz is not feathers. Some paleontologists claim that the dino-fuzz found on dinosaurs such as the Chinese Sinosauropteryx are "proto-feathers." By definition proto-feathers are not feathers. Others disagree, and point out that dino-fuzz is most likely collagen fibers found in the skin of most vertebrates, including sharks and humans. If dino-fuzz is protofeather, then sharks have protofeathers.
There are of course some fossils that have feathers, such as Caudipteryx and Protarchaeopteryx, that are claimed to be dinosaurs. However, these fossils have also been identified as flightless birds, or "prehistoric ostriches" by some ornithologists. Further, some theropods that have the skin preserved show no evidence of feathers, only scales.
The short answer to your question is that there is not one single dinosaur that has been found with feathers. The latest claim of a feathered dinosaur, namely Microraptor, is probably a bird, not a dinosaur. As Alan Feduccia of the University of North Carolina puts it, Microraptor is probably an avian non-dinosaur.
Further, the idea that feathers evolved originally as insulation is ludicrous, because dinosaurs were gigantotherms. They were huge and their surface area to body volume ratio is low, low enough that they don't need insulation or internal metabolic heat to maintain a high body temperature. Reptiles as small as monitor lizards are able to maintain a more or less constant body temperature in tropical areas without either internal metabolic heat or insulation. In fact, dinosaurs bigger than the woolly mammoth are simply not possible if they were endotherms. Dinosaurs would probably be the size of African elephants but no bigger if they were endothermic. Even African elephants need huge ears to get rid of excess internal body heat, and they cool themselves off regularly by going to water holes. Endothermy would have been maladaptive for the large dinosaurs in the warm Mesozoic.
Equally ludicrous is the idea that insulatory feathers could evolve into flight feathers. That would be analogous to creating a wing with dreadlock hair. The bats are smart enough not to evolve a wing with interlocking hair, they evolved a wing made of skin instead. A far more logical theory for feather evolution is for scales to evolve directly into large, solid aerodynamic feathers, like those found on Longisquama. Later, evolutionary experiments with weight reduction could have reduced the solid but functioning aerodynamic feathers into interlocking aerodynamic structures that we see in modern birds.
There is not a single piece of evidence that any dinosaur has feathers. Some of them do exhibit "dino-fuzz." Dino-fuzz is not feathers. Some paleontologists claim that the dino-fuzz found on dinosaurs such as the Chinese Sinosauropteryx are "proto-feathers." By definition proto-feathers are not feathers. Others disagree, and point out that dino-fuzz is most likely collagen fibers found in the skin of most vertebrates, including sharks and humans. If dino-fuzz is protofeather, then sharks have protofeathers.
There are of course some fossils that have feathers, such as Caudipteryx and Protarchaeopteryx, that are claimed to be dinosaurs. However, these fossils have also been identified as flightless birds, or "prehistoric ostriches" by some ornithologists. Further, some theropods that have the skin preserved show no evidence of feathers, only scales.
The short answer to your question is that there is not one single dinosaur that has been found with feathers. The latest claim of a feathered dinosaur, namely Microraptor, is probably a bird, not a dinosaur. As Alan Feduccia of the University of North Carolina puts it, Microraptor is probably an avian non-dinosaur.
Further, the idea that feathers evolved originally as insulation is ludicrous, because dinosaurs were gigantotherms. They were huge and their surface area to body volume ratio is low, low enough that they don't need insulation or internal metabolic heat to maintain a high body temperature. Reptiles as small as monitor lizards are able to maintain a more or less constant body temperature in tropical areas without either internal metabolic heat or insulation. In fact, dinosaurs bigger than the woolly mammoth are simply not possible if they were endotherms. Dinosaurs would probably be the size of African elephants but no bigger if they were endothermic. Even African elephants need huge ears to get rid of excess internal body heat, and they cool themselves off regularly by going to water holes. Endothermy would have been maladaptive for the large dinosaurs in the warm Mesozoic.
Equally ludicrous is the idea that insulatory feathers could evolve into flight feathers. That would be analogous to creating a wing with dreadlock hair. The bats are smart enough not to evolve a wing with interlocking hair, they evolved a wing made of skin instead. A far more logical theory for feather evolution is for scales to evolve directly into large, solid aerodynamic feathers, like those found on Longisquama. Later, evolutionary experiments with weight reduction could have reduced the solid but functioning aerodynamic feathers into interlocking aerodynamic structures that we see in modern birds.
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