> The retina is one of the body’s most energetically expensive tissues.
I never knew, but it explains why when you close to fainting you lose your vision. Or when you are working at high heart rate close to your maximum. It works as a kind of a warning sign, than you are probably shouldn't try it that hard.
> The lack of blood vessels could also offer birds the advantage of better vision.
Now they are ready to reintroduce blood vessels back, but this time behind the retina.
> Or when you are working at high heart rate close to your maximum.
When I was in college, running on the track, I decided to see how fast I could run by ignoring the stress and pain. My vision began rolling and surging in a weird way impossible to describe. I stopped and laid down on the ground, unable to do anything but pant.
I realized that what I had done was extremely stupid and never did it again.
Interesting title. These thoughts are before reading the article, use grains of salt as required.
I believe that birds brains are kind of uniquely advanced too. Lightweight (in terms of mass) structured differently to mammalian brains... I've heard a definition of sight as "a bit of the brain popping out for a look". I wonder if the same brain density tricks bird brains use are used in some parts of their vision system. This is all as my memory serves. Feel free to correct any mistakes in my understanding.
There's some very interesting work happening to understand their calls too. If (my) memory serves, there able to identify particular call types quite well now.
If someone calls you a "bird brain", perhaps that could be taken as a complement! Trying to do more with less!
Fascinating to also think that birds are of course evolved dinosaurs. Raptors of the sky. It would be fascinating to link whats being looked at here with any kind of data that can be pulled from fossil evidence (though there might not be much...). I wonder which unique bird genetic traits were useful or super enhanced dinosaur traits.
...I think the strong but light bone structure was something inherited from the dinosaurs too? Fascinating creatures.
On the face of it, seems sensible that avian evolution has spent many genetic GPU cycles to generate advanced vision needed to fly and hunt from the air.... One wonders which "subroutines" have been reused from dino-days, as mentioned.
It is plausible that the original non-avian theropod dinosaurs which gave rise to avian theropod dinosaurs like modern birds were more vision-oriented predators than mammalian predators.
That would have favored eyes built for sharper vision at the expense of higher metabolic demands.
The different evolutionary track may come from the fact that theropods stood upright on two legs, so they could scan farther across the landscape. Also, they were active during the day. Early mammals, by contrast, were mostly nocturnal, so hearing and smell mattered more than sharp vision.
Interestingly, humans have some of the best vision in the animal kingdom and humans are both upright standing and diurnal, i.e. active in the daytime.
> (tumor cells often use anaerobic glycolysis to make energy)
More generally, human cancers cells often seem like they've rolled-back to an earlier, atavistic set of behaviors.
I wonder if that's a "direction" of random mutations which is less-likely to be attacked by the immune system, because it leads to things that are less-alien because they were normal at one point. (Or may still be normal in limited contexts.)
Ex:
> The hallmarks of cancer are not the acquisition of novel behaviors due to genomic mutation but rather the re-deployment of ancient, unicellular programs that support survival of the cell at the expense of the host and break the contract of cooperation required for multicellular life.
I assumed this was more that the robust system survives. Oxidative phosphorylation is complicated, requiring many participating proteins in the pathway. If any of them are broken, that is it. Glycolysis is comparatively simple more likely to survive random mutation. Any cells which break glycolysis will die off.
Check out the book "The Red Queen". The author points out that even chromosomes fight for survival at the expense of other chromosomes and the body. X chromosomes try to destroy the Y chromosome, for example.
Soo evolution doesn't always optimize for biochemical efficiency in isolation. Sometimes it optimizes the whole system, and "wasteful" metabolism can be the right answer if it removes a bigger constraint.
I've only discovered Quanta this year but it's quickly become my favourite publication. The focus on quality articles across science, and especially pure maths, feels very unique. I don't know whether it's profitable or reliant on the Simons Foundation funding - but hopefully it's a sustainable business model that will stick around.
Damsgaard, C., Skøtt, M.V., Williams, C.J.A. et al. Oxygen-free metabolism in the bird inner retina supported by the pecten. Nature 650, 657–663 (2026).
Yet birds eyes still have nerves on top of light sensitive cells, obstructing the light. Birds also have a blind spot on each eye where nerves need to pierce the retina to go to brain.
Contrast with squid eyes, that have nerves underneath the light sensitive cells. No blind spots, better light sensitivity.
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[ 3.3 ms ] story [ 52.0 ms ] threadI never knew, but it explains why when you close to fainting you lose your vision. Or when you are working at high heart rate close to your maximum. It works as a kind of a warning sign, than you are probably shouldn't try it that hard.
> The lack of blood vessels could also offer birds the advantage of better vision.
Now they are ready to reintroduce blood vessels back, but this time behind the retina.
When I was in college, running on the track, I decided to see how fast I could run by ignoring the stress and pain. My vision began rolling and surging in a weird way impossible to describe. I stopped and laid down on the ground, unable to do anything but pant.
I realized that what I had done was extremely stupid and never did it again.
I believe that birds brains are kind of uniquely advanced too. Lightweight (in terms of mass) structured differently to mammalian brains... I've heard a definition of sight as "a bit of the brain popping out for a look". I wonder if the same brain density tricks bird brains use are used in some parts of their vision system. This is all as my memory serves. Feel free to correct any mistakes in my understanding.
There's some very interesting work happening to understand their calls too. If (my) memory serves, there able to identify particular call types quite well now.
If someone calls you a "bird brain", perhaps that could be taken as a complement! Trying to do more with less!
Fascinating to also think that birds are of course evolved dinosaurs. Raptors of the sky. It would be fascinating to link whats being looked at here with any kind of data that can be pulled from fossil evidence (though there might not be much...). I wonder which unique bird genetic traits were useful or super enhanced dinosaur traits.
...I think the strong but light bone structure was something inherited from the dinosaurs too? Fascinating creatures.
On the face of it, seems sensible that avian evolution has spent many genetic GPU cycles to generate advanced vision needed to fly and hunt from the air.... One wonders which "subroutines" have been reused from dino-days, as mentioned.
That would have favored eyes built for sharper vision at the expense of higher metabolic demands.
The different evolutionary track may come from the fact that theropods stood upright on two legs, so they could scan farther across the landscape. Also, they were active during the day. Early mammals, by contrast, were mostly nocturnal, so hearing and smell mattered more than sharp vision.
Interestingly, humans have some of the best vision in the animal kingdom and humans are both upright standing and diurnal, i.e. active in the daytime.
Ha! It’s the same thing.
They start out saying oxygen vessels partially and subtly occludes vision.
So the bird's eye doesn't suffer from this disadvantage.
In other words: It uses 15x more energy but presumably also sees 15x sharper and more into the distance than our human eye.
Sounds proportional at most, but certainly not inefficient for the bird's purposes?
Aren't crocodiles and dinosaurs seperarte branches ?
More generally, human cancers cells often seem like they've rolled-back to an earlier, atavistic set of behaviors.
I wonder if that's a "direction" of random mutations which is less-likely to be attacked by the immune system, because it leads to things that are less-alien because they were normal at one point. (Or may still be normal in limited contexts.)
Ex:
> The hallmarks of cancer are not the acquisition of novel behaviors due to genomic mutation but rather the re-deployment of ancient, unicellular programs that support survival of the cell at the expense of the host and break the contract of cooperation required for multicellular life.
https://www.sciencedirect.com/science/article/abs/pii/S00796...
https://www.hopkinsmedicine.org/news/newsroom/news-releases/...
https://www.amazon.com/Red-Queen-Evolution-Human-Nature/dp/0...
This is one of the most fascinating books I've ever read.
https://www.nature.com/articles/s41586-025-09978-w
Damsgaard, C., Skøtt, M.V., Williams, C.J.A. et al. Oxygen-free metabolism in the bird inner retina supported by the pecten. Nature 650, 657–663 (2026).
Contrast with squid eyes, that have nerves underneath the light sensitive cells. No blind spots, better light sensitivity.