Live Birth In Ancient Marine Reptile

Afton T. -- A recent study of a fossil plesiosaur answers a long-standing question- did plesiosaurs give birth to their young? This fossil, found sitting in a museum basement, seems to point to yes. Encased in its ribcage is a small, perhaps ⅔ formed, fetus. The scientist believe that the baby is too helpless and undeveloped to survive in the dangerous Cretaceous oceans. It had no teeth, tiny flippers, and would not have been able to move around. The fossil was excavated in Kansas in 1987 by the owner of the land, Charles Bonner. It lay in the basement of a museum until recently, when it was decided that the fossil would be placed in a new exhibit. Professor O’Keefe, who was called in to work on the fossil, didn’t immediately think of the scientific implications. His first thought, he remembers, was: “It’s really cool, you don’t often see fossils that neat.” Of course, there are other theories for how this happened. One theory is that another fetus of the same species fell on the adult, and they were fossilized together, but this is unlikely. The adults ribcage would have had to be opened up, and many other circumstances would have had to happen for this to be true. Another theory is that the smaller one was eaten, but this, too, is unlikely, because the stomach acids would have eaten away the cartilage, of which there is evidence in the baby fossil.

    I liked this article for many reasons. One, I find paleontology very interesting, so reading an article about it is always fun. I also liked this article because it showed a different side of plesiosaurs: one of kindness and gentleness, not just a strong predator. I find it interesting that they seem to have given live birth, but it does make sense, because they are not really built for protecting eggs. This article also made me ask another question: Are whales and dolphins descendants of the plesiosaurs? Whales and plesiosaurs do seem to have a few traits in common; they both are aquatic lifeforms, and they both give live birth. Doesn’t it make sense for them to have possibly evolved from the same ancestor, or for whales to have evolved from the plesiosaurs? 


Link:  Live Birth In Ancient Marine Reptile