Two-headed Reptile Fossil Found in China

[TheBORG] writes "A tiny skeleton from the Early Cretaceous shows an embryonic or newborn reptile with two heads and two necks, called axial bifurcation ('two-headedness') (a well-known developmental flaw among reptile species today such as turtles and snakes) was found in China by French and Chinese paleontologists recovered from the Yixian Formation, which is nearly 150 million years old."

The ass casts the deciding vote

[Harmonious Botch]

Seriously, I wonder if there is any evolutionary connection between the placement of some neural processing in the hindquarters and the frequency of two heads in the reptilian class, as if mother nature was experimenting with protecting brainpower by moving it around to a safer location, or by duplicating it. Since reptiles had the first big brains, this may have been the first occasion to arise in which trying to protect brains might be worth the expense.

Re:The ass casts the deciding vote

[SinGunner]

but how similar would the brains be? all the inputs would be different save for some aspects of feeling, though the general nature of the inputs would be very similar. it'd be hard to test too, eh?

Re:The ass casts the deciding vote

[greg_barton]

I'd venture to say a brain in the chest cavity would make a hell of a lot more sense...

How would you dissipate heat from a brain in your chest?

Developmental Flaw?

[rhkenji]

Why is it when something is out of the ordinary, its a flaw? axial bifurcation ('two-headedness') (a well-known developmental flaw among reptile species today such as turtles and snakes).. Every species on earth has a flaw that helps it survive in its environment. As far as I can see, Two Heads are the same as having two hands. Its not a flaw, its a step in evolution. When we see something like 6 fingers in a human, we think its a flaw. Why do we think that these defects are flaw not as step to human evolution? I see no flaw but evolution.

Re:beeb article and questions

[glwtta]

Does it act as a redundant system used only if the primary one fails or do they actually process stimuli from both heads?

As far as I know, animals don't work that way - all "redundant" systems are always active, they just have enough "capacity" to pick up the slack if one part fails.

I seem to recall and article about a two-headed turtle. The dude who owned it said that it generally seemed to get around ok; though sometimes the heads would fight over food and such. But then it's a turtle, they aren't exactly known for their active life-style. From the way they talked about it, it did seem to be "two turtles with one body", rather than "a turtle with two heads" kind of thing; which is probably why you never see this in anything more advanced than reptiles.

The embryo "damage" is the same thing that causes conjoined twins - these guys are conjoined at the body. I am not sure what you mean by "accepted", these things happen, there's not much to accept (unless of course god is testing our faith again).

Re:The ass casts the deciding vote

[Sique]

Dual-headed miscreants are also common with amphibia (frogs, newts), not only with reptilia. But because amphibia are often prey to a lot of predators, the dual-heads don't survive very long. An interesting exception is the site of the Tchernobyl nuclear plant, where after the nuclear catastrophe in 1986 most of the predators have left, and now the nearby lake shows miscreated newts and frogs more often. It's not because of the background radiation (it's back to normal levels at least in the lake), but because of the lack of predators that those animals survive so often.

Re:The ass casts the deciding vote

[kooky45]

The brain also generates a substantial amount of heat. In humans it's thought one of the reasons our ancestors started to stand vertically was so their heads could be higher from the ground and stay cooler in the hot climate where they evolved. Any animal with a large amount of body tissue surrounding their brain (in a chest cavity) would suffer overheating, and having the brain near the surface of the body makes it more vulnerable to damage from bumps, falls and attacks.

Polycephaly in NON-reptiles

[DrYak]

which is probably why you never see this in anything more advanced than reptiles

You DO [wikipedia.org] see polycephaly in things more advanced than reptiles, although it's less frequent.

(And a greater part of the organism is redundant in mammals that survive, as in the above Siamese twins).

Re:Buridan's Dinosaur

[KingNaught]

You don't have to imagine just look here http://en.wikipedia.org/wiki/Abigail_and_Brittany_ Hensel [wikipedia.org] just saw them on TV last night their 16 now and pretty healthy except for some back problems. Their not monsterous looking in fact their fairly cute looking girl(s)