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Re: Live Births
I just felt I had to clarify something in regards to garter births, or for that matter, most reptilian "live births". Garter snakes do not give true "live birth" as compared to placental mammals.
The original assumption (always bad, but even in science sometimes needed in order to get things going!) was closer to the truth, as in egg shells disolving and such... except their really isn't much of an egg shell in the first place! It's a membrane. Here are the 3 words we need to compare:
Viviparous - where developing eggs nurtured by the mother and then continuously nurtured until birth via umbilicus. All mammals, except 2!
Oviparous - where developing eggs are initially nurtured by mother and later embryos are nurtured by a placental yolk within the egg/ incubated and hatched (shell) independent of mother. Lots of critters! Reptiles, birds, bugs....
Ovoviviparous - where developing eggs are initially nurtured by mother and later embryos are nurtured by a placental yolk within the egg/ "incubated" and "hatched' (slipping through the membrane - no shell) via the mother.
Garter snakes, most vipers, most boas... are all OVOVIVIPAROUS!
At least that's what I have learned. Please correct me if I am wrong.
Last edited by Steven@HumboldtHerps; 06-23-2008 at 12:06 AM.
Reason: details
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