Dinosaurs Layed Eggs Like Birds Not Crocodiles

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(A) The pair of eggs sit at the bottom of the fossilised pelvis (B) An egg found inside the female oviraptorosaurian. The blue color of the egg shell fragments is not the original color, though the texture of the shell pieces probably resembles the original texture of the egg.

From New Scientist .
This is incredible. Paleontologist in China have found dino eggs in the body of the mother!

The first dinosaur eggs found complete with shells in the body of the mother has solved the long-standing mystery of how dinosaurs laid their eggs. The evidence shows they laid a clutch in a series of sittings, like birds, rather than all at once like crocodiles and other living reptiles.

Oviraptors are part of the wide-ranging group called theropods, which also includes Tyrannosaurs and the ancestors of birds. Their fossilised nests are well known in China, typically including over a dozen elongated oval eggs in two rings.

Too little is preserved of the new find to identify the particular species, but the newly eggs looked ready to be laid, says Tamaki Sato of the Canadian Museum of Nature in Ottawa.

The best-preserved egg of the find is nearly 20 centimetres long and 6 to 8 cm wide, although somewhat deformed. Sato says the egg’s shape and microscopic structures match those of some previously found eggs.

The pair of eggs show the oviraptor developed one egg at a time in each of its two oviducts, most probably laying one pair at a time in the nest, Sato suggests.

That puts it somewhere between the primitive reptilian form of crocodiles and the more advanced form of the birds, consistent with the theory that birds evolved from dinosaurs related to oviraptors.

Gee, sounds like a transitional fossils to me. An yet more eveidence of “macroevolution”. With finds like this happening on a regular basis I’m almost starting to feel sorry for the creationists!

More Info

Added later: Pharyngula has a post as well – didn’t realize he was doing a post on it but he approaches it from a slightly different angle.

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5 Responses

  1. I thought this had been established beyond doubt years ago. I’m wondering about the whole archaeopteryx / pterodactyl bit… When DID feathered birds actually BEGIN? There seems to be a huge leap in the fossil record that leaves me sleepless nights.

    And those Neanderthals: Was it competition, interbreeding, or just plain old warfare that did them in? I’m leaning towards interbreeding. I mean, if FOXES and DOGS can produce offspring, hey… Besides, we all know that men will fuck ANYTHING, right?

    Get back to me on that will ya? Love this blog. Very stimulating read.

  2. I know you must be kidding about feeling sorry for the creationists. Good joke!
    I love looking at the fossilized egg. It is so evocative of tension between life and death– to be an egg, and yet to be millions of years old. It’s like an incongruous juxtaposition– an ancient egg. It’s a great find.

  3. How very interesting. I never thought about the difference until you blogged about it.

  4. to Rexroth’s Daughter:
    That is a good point, I hadn’t thought about it that way. Kind of shows how scientific knowledge and the “Creative Impulse (name of an art history textbook I used in college)” can sometimes go hand in hand.

  5. Citrus:
    I think I will actually do a post on that when I get a minute.

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