I've seen a few pictures of those, and frankly, i've lost my lunch. I'm a bit too weary to go back to those sites, so does anyone mind telling me what causes them and how long they live?

usually they die under a week,

 

I will quote OMIM here:

 

"(1) In the harlequin fetus, an abnormal x-ray diffraction pattern of the horn material points to a cross-beta-protein structure instead of the normal alpha-protein structure of keratin. (2) Bullous ichthyosiform erythroderma (113800) is characterized by an early formation of clumps and perinuclear shells due to an abnormal arrangement of tonofibrils. (3) In the Curth-Macklin form of ichthyosis hystrix (146590), concentric unbroken shells of abnormal tonofilaments form around the nucleus. (4) In ichthyosis hystrix gravior (146600) only rudimentary tonofilaments are found with compensatory production of mucous granules"

 

however, there has been one case where a harlequin fetus managed to live to his teenage years. I'm not sure if he's still alive.

 

 

also for the curious minded: do not image google it unless you know what you are about to see.

Ew. Anyway, after doing some research and having to take some Pepto Bismol, there was one that actually survived to adulthood, and, get this, he's a TRIATHLETE.

 

Also, i've been wondering.. the plated scales and the proto-eyes.. that looks quite a bit like the Devonian fish. I know that the whole "stages of evolution in the womb" thing is false, but it's quite a curiosity.