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Evolution: bruh all that matters is that you are a horndog.
It’s so weird thinking about how we’re just copying DNA. That’s pretty much the purpose of life; replicate these strange molecules as much as possible. Consciousness is some unintended byproduct of the ‘copy forever’ algorithm.
And the contents of the information being copied is basically a recepie for building a machine that can make copies of the information needed to build that machine…
dat pelvis 🫦
Bro myopia is the least stupid part of our eye design problems. Our retinas are built entirely backwards for no other reason besides evolution making a mistake and then duct taping over it too much to fix it later.
If your retina was the right way around (like cephalopod eyes) you would have:
- No blind spots
- Higher fidelity vision even with the same number of receptors since the nerves and blood vessels wouldn’t interfere like they do now
- much lower likelihood of retinal detachment since you could attach it for real in the first place
- possibility for better brightness/darkness resolution since blood supply could be greater without affecting light passage
- possibility for better resolution because ganglion nerves can be packed more densely without affecting light passage
- The ability to regenerate cones and rods because you could, again, ACTUALLY HAVE SUPPORT CELLS WITHOUT BLOCKING LIGHT TO THE RETINA
Our eyes are built in the stupidest way possible.
Another fun fact: retinol is regenerated by your liver. Not your eyes, not some part of your brain, not some organ near your head like your thalamus which could probably get the job done if it tried, your fucking liver. Your eyes taking a while to adjust to the dark has basically nothing to do with your eyes; it’s because of the delay in adjustment by your fucking liver to produce more retinal, dump it into your vascular system and wait for it to hopefully reach your eyes. Why are we built like this?!
Edit: A few comments asked for sources on the relation between dark adaptation and liver vitamin A. So I went looking for sources. It was honestly somewhat difficult to find information, but I was able to find two different case studies showing that night blindness in patients with damaged livers. Specifically these individuals had liver damage that affected their serum Vitamin A levels. And after raising their vitamin A levels, their symptoms improved.
This study details a patient with normal day vision and no other ocular problems besides being unable to see at night.
The patient had a medical history of stage 4 non-alcoholic liver cirrhosis, which led to a malabsorption of vitamin A, as confirmed by the very low vitamin A level in the serum analysis… …Subjective improvement in symptoms, along with better performance on visual field, were noted after initiating oral vitamin A supplementation for 6 months.
This study details a patient with night blindness caused by low levels of vitamin A presumably due to Hepatitis C.
Case description: This case describes a 64-year-old female patient with symptomatic VAD, likely secondary to liver cirrhosis in the setting of Hepatitis C. The patient presented with night blindness and blurry vision. She was successfully managed with direct replacement of Vita-min A.
These studies do show that dark adaptation is dependent on vitamin A produced by the liver, but I’ll be the first to admit it’s not exactly conclusive evidence of my initial claim that the liver must respond to dark conditions increasing retinol concentration in the blood in order for rod cells to function properly in low light conditions. That is a possible explanation for these case studies but not necessarily the only one, so take my last fun fact with a grain of salt.
Source that retinal concentration is related to dark adaptation?
I’m not OP and I’m not an expert, but I know that the production of rhodopsin requires retinal. Rhodopsin is a light-sensitive protein our eyes use to see in low-light conditions, and is essential for our night vision. Retinal and retinol are not the same thing, but they both come from Vitamin A, and convert into each other during the visual cycle. Which means that a deficiency in Vitamin A = a deficiency in retinol, retinal, and rhodopsin, which in effect leads to night blindness.
But I’d like to know more/get a source for OP’s liver connection. I know most of our retinol is stored in the liver. However, I’m having difficulty verifying their claim that the delay in night vision onset is due to it traveling from the liver to the eyes. From what I can find, the retinol ligand that produces rhodopsin already exists in mammalian eyes (and persists there as part of the aforementioned visual cycle.) So the argument that night vision takes so long because retinol needs to transfer from the liver to the eyes is suspect.
Unfortunately, search engines absolutely suck these days, and almost every article I can find is behind a fucking paywall. So I’m struggling to find information that can either confirm or deny OP’s claim.
OP, please provide a source! Inquiring minds want to know more!
Another fun fact: retinol is regenerated by your liver. Not your eyes, not some part of your brain, not some organ near your head like your thalamus which could probably get the job done if it tried, your fucking liver. Your eyes taking a while to adjust to the dark has basically nothing to do with your eyes; it’s because of the delay in adjustment by your fucking liver to produce more retinal, dump it into your vascular system and wait for it to hopefully reach your eyes.
This is fascinating, I had no idea that there was another mechanism at play to improve low light vision other than pupil dilation
Or that it got stuck in the figurative basement organ where a silly amount of bio-chemistry is stuck because evolution kinda shrugged a few million years ago.
Just one more reaction, bro, I promise, I’m not just making up new organic compounds for fun.
The nerve thing bothers me. I wish to learn nothing more of it
no but honestly, periods are great. The feeling when all that extra blood leaves your body is amazing. Guys will never know what it’s like being somewhere and sudenly feeling warmth blood running down your legs out of nowhere. Amazing. 10/10 would ome back as a woman again
What’s up with the earthquake one?
I’m sorry gotta go on a tangent rant I was recently talking to a friend about pregnancy and it is fucking mind boggling. Organs shift, skeleton changes, and then all the crazy chemical stuff going on too.
The fact that millions of women want this and many experience it more than once is just mind boggling to me.
Eta: sorry my tangent was inspired by “childbirth is fun” but only showing the pelvis.
Wait till you hear about caterpillars.
Evolution is one hell of a drug
Optimization was never the goal. It just has to function well enough for a sufficient portion of the species to reproduce.
Literally the evolutionary equivalent of “eh, good enough”
What’s the smart nerve taking a detour one?
And it does that for both humans… And giraffes. Going from the brain, several meters down to the heart, then all the way back up to the larynx.
Wisdom teeth were amazing to have back when dental care didn’t exist and our teeth fell out from decay or injuries.
Why?
Because in prehistoric humanity, without the knowledge of toothcare or ease of access to scrubbing agents, your teeth would rot out in old age(about 20), but then the wisdom teeth would grow in, and you might barely live long enough to be a withered old husk and maybe see your grandkids born(about 30). The before times were rough.
