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Sage
04-11-2012, 05:47 AM
I know, it's really strange, but I'm hoping maybe there's a biologist here who knows the answer anyway.

When I was in college, I dissected an alligator and found babies inside instead of eggs. Since it was ages ago and I've long since lost the notes where my professor explained why that was, I've been looking online for a reason for this, and I haven't come up with any answers. Usually, alligators lay eggs and then hatch them outside the body. I can find all sorts of details on the mothers protecting their eggs, the babies talking inside them, how they hatch, but nothing on why a mother might have hatched babies insider her where gravid eggs should be.

It's not that important to the story, and I could change it, but I think it makes the dissection scene a little more interesting. But I won't have it in there if I can't find out the reason behind it.

Anybody know why this would happen?

Silver King
04-11-2012, 06:16 AM
...Anybody know why this would happen?
Yes. The female consumed her hatchlings, which isn't that unusual. It's also possible that you'd dissected a male that had done the same thing and mistaken it for a female.

Sage
04-11-2012, 06:36 AM
I had thought about that, but wouldn't that be in a different part of her body?

Sage
04-11-2012, 06:41 AM
Thinking about it, I can definitely have that be the answer (the boys were maybe looking in the wrong place), if nobody knows/I can't find the answer. But I'm pretty sure that in the real-life example, we were looking for eggs and found babies in the same spot and our professor had a reason for that.

Puma
04-11-2012, 07:02 AM
There was another similar thread to this about a year ago - I think started by Euclid. There was an answer and the key words were ovoviparous and viviparous (or similar). His question may have related to dinosaurs but I can't quite remember. If you can't find anything, pm him and see whether he can help you. Puma

Puma
04-11-2012, 07:10 AM
Okay, don't think you have to bother Euclid (he and I had talked about this back when he was looking into it.) I went back in my files and found a couple things that might help.

This egg vs. live birth question first spurred Shine's curiosity when he found that half of all Brindabella lizards lay eggs. The other half give birth to fully formed babies. Shine did further research and found:

Egg laying and live birth can occur in reptile species that are evolutionarily very similar. (Boas and Pythons)
Egg laying and live birth can occur even within the same species. (Bougainville's Skink)
Reptile egg layers have evolved into live bearers in at least 100 different origins. (The differences in reproductive methods have been proven to be genetic .and not short term adaptations. It is believed that live birth is an advanced trait.)
In all cases of reptilian live birth evolution, there is a climatic pattern.

Silver King
04-11-2012, 07:11 AM
Thinking about it, I can definitely have that be the answer (the boys were maybe looking in the wrong place), if nobody knows/I can't find the answer. But I'm pretty sure that in the real-life example, we were looking for eggs and found babies in the same spot and our professor had a reason for that.
I'm not a biologist; but as far as I know, alligator eggs are incubated outside of the womb, always, and never inside its parent.

Sage
04-11-2012, 04:17 PM
Cool, I'll look further into it, and use the "eating their young" reason if I don't find anything else

NDoyle
04-13-2012, 06:46 AM
As an interesting aside: the temperature at which an alligator egg incubates determines the sex of the hatchling! Nests constructed at damper locations with cooler temperatures produce all females. Males come from nests built in warmer locales.

Fenika
04-14-2012, 06:05 AM
The kakapo somehow does a similar thing with male/female young based on availability of food. Thats a NZ parrot though. Or maybe Im confusing it for another rare NZ bird...

/end derail aside

Sage
04-14-2012, 09:35 PM
I'm wondering if maybe the mother was killed shortly before she would have deposited her eggs, and what they use to euthanize her didn't kill the babies, which hatched in her body, then died.

JimmyB27
04-20-2012, 02:35 PM
Remembered this thread when I saw this (http://www.bbc.co.uk/news/17769677) on the BBC News site. Okay, so it was a chicken, not an alligator, but the principle might hold?