http://video.sympatico.msn.com/v/en-...ncastrangenews

The first part of this report is kind of near, all the two headed animals. At the end it mentions something about two two-headed snakes mating potentially...I'd say if anything, since it's developmental, the babies would come out normal for the most part (maybe a slightly higher % of two headers if it's a genetic cause). Anyways, ignore the other reports on there and ther interesting one is first.

People in St.Louis, let us know how it is.

As far as I know this has never been proven to have any genetic connection. It is, as you put it, simply an accident in development, like siamese twins in humans.
In fact several years ago there was a group attempting to deliberately breed to produce 2 headed animals.
They had no luck.

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Merlin,
What's Life Without A Little Magic!

The ability to produce oranisms with mutations involving "extra parts" comes from the genetic ability to produce twins from divided ovum. When the ovum "egg" is fertilized it develops stem cells which are essentially universal cells, if there is a disruption or split in the development, the cells will divide and produce two off spring from the same single egg, thus producing identical twins which are typically under weight or under developed. If there is a disruption in development after the division period, meaning the single ovum fails to completely divide then it will cause either shared or partial embryonic development. Shared basically being 2 complete organisms developing together as one, thus siamese twins; and partial meaning a portion of an oranism is recreated, in severe cases this can lead to parasitic twins, in less severe cases, it would lead to extra organs or appendages such as extra limbs or a second head in this case.

On the other side of the fence, there is the potential for a developmental mishap to occur, figuring in development, literally millions of cells replicating at insane rates, it is a wonder that there are not more unconventional growths and developmental issues.

Breeding two 2-headed animals will up the chances of twins (more than likely), but most likely not the number of 2-headed animals. It is a nice thought, and someone will probably make a **** of a campaign out of it, but there is no known genetic coding that I have ever read saying an organism will develop 2 or more of anything consistantly, otherwise there would be a much bigger market for things like that, and the survival rate would be much higher, most animals born with such severe mutations will not live very long.

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“The most exciting phrase to hear in science, the one that heralds new discoveries, is not ‘Eureka!’ (I found it!) but ‘That’s funny…'"
- Isaac Asimov



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I'd like to input that genetics can make you slightly more susceptible to producing siamese twins, remembering that it CAN Be a genetic problem leading to a poor split of the ovum. This case isn't the norm though. Well said though, Mr.Hickey.

In the case of two headed animals, like I saw with that stillborn gold skink "headley", I believe it's a bit more in depth than just simple siamese twins...either that or it could just be a HORRID "split" of the ovum. Could be an extreme "siamesing" (lol, new word coined here first right now).


Anyways, all I wanted to draw attention to is the fact that there's an exhibit and I KNOW there is some people in that region. I'd like pics, that's all.

Anyone know if true twins (not siamesed, lol) even occur in egg layers? If so, how often does it happen?

If the species is one in which the eggs are fertilized internally, than it would be possible for twins to occur, but how on earth would you know if an egg layer had twins? I think the only way to tell would be through genetic testing.

I have pictures of siamese red eared sliders that I babysat for about a week while the guy who bought them went out of town. They died few weeks after I returned them though. I don't know if their death had to do with negligence on part of the keeper or if their short life-span was due to complications stemming from their mutation. The turtles could not swim because they were attached at the belly so they had to be kept wet without being submerged completely and they had to be rotated every so often.

It would have to do with overall ovum development, the egg you see externally is already coded with 50% of its genetic code, if there is a problem with this development meaning there has been improper coding, gaps in coding, and/or faiure to complete coding, there is the possibility of over/under development, lack of development, or repeated development meaning the very slim, basically unheard of development of two oragnisms within one egg; this is more commonly seen by the presence of extra limbs or apendages, one of which is the second head.

So... yes you could possibly have identical twins within one egg, but it is such complicated mistake in genetic coding that the embryo(s) would probably die before reaching anything resembling a seperate functioning organism. It would more than likely die and be absorbed into the other developing organism where the stem cells or other equivalent cells would be used to develop parts of the other organism.

Basically in non scientific terms it could happen but it is so far fetched that it has never been seen or actually heard of just speculated upon in a few under published journals that no one ever actually looks at as a possibility.

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“The most exciting phrase to hear in science, the one that heralds new discoveries, is not ‘Eureka!’ (I found it!) but ‘That’s funny…'"
- Isaac Asimov



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