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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."
Especially after seeing the photo of a sketch of some cartoon character at the story.
Evolve radiating appendages that are highly vascularized to move blood rapidly away from the hot "core" with the brain.
Doesnt't sound plausible because high blood flow at those rates exposes you to serious damage by relatively small injuries.
I'd venture to say a brain in the chest cavity would make a hell of a lot more sense and invest in faster nerves for the ears and eyes
If it made more "sense" to have the brain in the chest, we would have brains in our chests. It's just pointless to argue with mother nature when it comes to design. You can probably point to some kinks that specific species are still working out, but anything this universal is so damn near optimal that it's awe-inspiring.
I suspect the answer here is that there's no such thing as "faster nerves"; you'd have to increase nerve cell length to cut down on the number of synapses, which would make them more fragile, and, more importantly, less manageable (and still wouldn't make up for the comparatively huge distance). Come to think of it, it's the old "higher throughput" == "lowered responsiveness" problem.
Plus, the head is better protected than the chest; it would probably add an inordinate amount of weight to the skeletal structure to fortify it to the same degree. Also, maintaining the blood-brain barrier would probably be tricky without the separation that the neck provides (not to mention that your circulatory system would be right next to the thing).
sic transit gloria mundi
It's probably called a flaw because the development of the extra head isn't determined by the creature's genes. It's a trait that can't be passed to its offspring, so it has no part in evolution.
Maybe