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this reminds me of that time blowhard Richard Dawkins disected an animal (can't remember which) and proceeded to bang on about how stupid the vagus nerve is, wa

this reminds me of that time blowhard Richard Dawkins disected an animal (can't remember which) and proceeded to bang on about how stupid the vagus nerve is, wandering all over the place as it does for no apparent reason. People used to say the same of the appendix and adenoids; that they're pointless vestiges, the blindness of evolution, contingent structures. Dawkins said obviously the nerve should simply connect directly instead of following its ancient evolutionary program up and down and around the organs. A classic case of Chesterton’s Fence

madengr 7y ago
It was a giraffe, for which that nerve just seems out of place.
mtts 7y ago
He said it would have been stupid had someone designed it that way but given that it evolved it made perfect sense why it was the way it was.
- Uhuhreally 7y ago
  he said it was understandable why it was the way it was but implied that it "would be better" if it went directly - his tone was scoffing
z3t4 7y ago
Are there any interesting theories? I think a lot can be attributed to just randomness. Some time in the evolutionary process we got infected by a bacteria, the mitochondria is now a vital part in our bodys energy system...
- gus_massa 7y ago
  One of the nerves that go from the brain to the eye and is hooked by the top part of the aorta artery. In the original version, it was in some animal like a fish, and the top part of the aorta was in the gills, so the way from the brain to the eye though the hole that is below the aorta was a straightforward path. A few million years later, when we lost the gills, and got a neck, the top part of the aorta moved inside the chest to avoid a stupid long trip to the neck and back (and probably lost a lot of speed in the blood). The nerve was hooked, so the aorta got shorter, but the nerve has to go down to the chest, pass below the aorta, and then go back to the eye. In the case of the giraffe, the trip to the chest and back to the eye is stupidly long. The problem with evolution is that mutation can do only small changes (most big changes are just deadly). The connections of the nerve and the artery form very early in the development of the fetus, when it looks almost like an ugly fish. You can't unentangle the nerve and the artery later. More details: https://en.wikipedia.org/wiki/Recurrent_laryngeal_nerve https://en.wikipedia.org/wiki/Recurrent_laryngeal_nerve

madengr 7y ago

It was a giraffe, for which that nerve just seems out of place.

mtts 7y ago

He said it would have been stupid had someone designed it that way but given that it evolved it made perfect sense why it was the way it was.

Uhuhreally 7y ago
he said it was understandable why it was the way it was but implied that it "would be better" if it went directly - his tone was scoffing

z3t4 7y ago

Are there any interesting theories? I think a lot can be attributed to just randomness. Some time in the evolutionary process we got infected by a bacteria, the mitochondria is now a vital part in our bodys energy system...

gus_massa 7y ago
One of the nerves that go from the brain to the eye and is hooked by the top part of the aorta artery. In the original version, it was in some animal like a fish, and the top part of the aorta was in the gills, so the way from the brain to the eye though the hole that is below the aorta was a straightforward path. A few million years later, when we lost the gills, and got a neck, the top part of the aorta moved inside the chest to avoid a stupid long trip to the neck and back (and probably lost a lot of speed in the blood). The nerve was hooked, so the aorta got shorter, but the nerve has to go down to the chest, pass below the aorta, and then go back to the eye. In the case of the giraffe, the trip to the chest and back to the eye is stupidly long. The problem with evolution is that mutation can do only small changes (most big changes are just deadly). The connections of the nerve and the artery form very early in the development of the fetus, when it looks almost like an ugly fish. You can't unentangle the nerve and the artery later. More details: https://en.wikipedia.org/wiki/Recurrent_laryngeal_nerve https://en.wikipedia.org/wiki/Recurrent_laryngeal_nerve