Need requires context. “if they don’t have it, they don’t need it to survive”. And survival is conditioned upon the environment. If something emerges that exploited the blindspot, then we’d need it to survive.
What was the evolutionary pressure that caused receptor orientation to be different in cephalopods that vertebral animals didn’t encounter? Or did they encounter it and have other adaptations that allowed it to deal with them.
There’s no guarantee that an evolutionary search process will lead to a globally optimal solution. It’s the same thing with evolutionary algorithms in computing
The problem is that the landscape of where the global maxima are changes faster than evolution can keep up. If the environment were entirely static, then yes, mathematically speaking any random optimizer would eventually reach a global maximum. However, it could take, say, 1050 years or more to jump from a local maximum to a distant, higher maximum.
Imagine an alligator. Quite good at catching prey with their current anatomy.
An alligator that shoots laser beams for tracking and bullets would be even better. There’s however no path from their current anatomy to this state, regardless of the randomness and timescale for mutations. In fact, in order to achieve this higher state several non advantageous intermediates would be necessary and therefore never selected for.
So no, evolution can’t achieve global maxima, it can however optimize the shit out of what it’s given to work with.
There needs to be pressure for animals with a mutation to reproduce more or animals without the mutation to die before reproduction. Like a disease for example. Otherwise the genes don’t spread and just disappear in the soup of all that species genes and never become dominant. Without any evolutionary pressure the mutation will only spread in one family and probably be gone after a few generations. Like there are human families that are more likely to produce offspring with 6 digits on their hands, but since it isn’t more advantageous than 5 digits (6 digit people don’t produce more offspring and 5 digit people aren’t more likely to die before reaching reproductive maturity) that mutation doesn’t spread across the entire species. Sure if you could sample the genome of every human on earth and identify every advantageous gene mutation you could build the ultimate human DNA. But that’s artificially created, something like that will never happen through evolutionary pathways.
no they’re not. by definition if you don’t have what you need you don’t survive. we definitively don’t need it. or at least haven’t for millions of years. that’s different from saying we wouldn’t benefit from it.
although that’s not a guarantee either. more information isn’t always better.
Okay true, but I still feel the comment was misleading. If it were phrased as “If vertebrae don’t have it, it means it wouldn’t improve their fitness” it would be wrong. I’ll admit that the comment as worded is true, but it does depend on a very literal interpretation of what “needs” means. Why even post that? In my opinion, that makes it low-quality content, so worth a downvote.
disagree. again, we don’t even know if such a change would be beneficial.
also, more importantly, the post is entirely stupid.
suboptimal by what measure? became disadvantageous how? against what? last time i checked ve**rtebrates were still dominating. now even more than they did during the ages of dinosaurs.
evolution was too late to correct it… what? first of all, is it even a mistake to correct? where’s the evidence of that? second of all, did evolution stop? too late how? it’s complete bullshit, and if anything the original comment wasn’t harsh enough on it.
I’m not claiming that this change in how eyes work would be an improvement. I’m claiming that the following does not hold generally: “Doesn’t have adaptation X ⇒ adaptation X would not improve fitness.”
yeah but that’s not part of the original comment, not even by implication. the opposite is also not true so it doesn’t factor in at all. even though you’re not claiming it would be an improvement the original post clearly does and that’s what the top level comment is countering.
If vertebrae don’t have it, it means they don’t need it.
that’s not how evolution works. Evolution is not able to produce global maxima, only local maxima.
Not really. Needs is a fairly strict word. If it was needed they would not survive without. Useful, i agree with you
Need requires context. “if they don’t have it, they don’t need it to survive”. And survival is conditioned upon the environment. If something emerges that exploited the blindspot, then we’d need it to survive.
What was the evolutionary pressure that caused receptor orientation to be different in cephalopods that vertebral animals didn’t encounter? Or did they encounter it and have other adaptations that allowed it to deal with them.
Dont they eventually produce global maxima by iterating towards it through the many degrees of freedom allowed by crazy mutations and time?
There’s no guarantee that an evolutionary search process will lead to a globally optimal solution. It’s the same thing with evolutionary algorithms in computing
The problem is that the landscape of where the global maxima are changes faster than evolution can keep up. If the environment were entirely static, then yes, mathematically speaking any random optimizer would eventually reach a global maximum. However, it could take, say, 1050 years or more to jump from a local maximum to a distant, higher maximum.
Ah good point, thanks
Imagine an alligator. Quite good at catching prey with their current anatomy.
An alligator that shoots laser beams for tracking and bullets would be even better. There’s however no path from their current anatomy to this state, regardless of the randomness and timescale for mutations. In fact, in order to achieve this higher state several non advantageous intermediates would be necessary and therefore never selected for.
So no, evolution can’t achieve global maxima, it can however optimize the shit out of what it’s given to work with.
There needs to be pressure for animals with a mutation to reproduce more or animals without the mutation to die before reproduction. Like a disease for example. Otherwise the genes don’t spread and just disappear in the soup of all that species genes and never become dominant. Without any evolutionary pressure the mutation will only spread in one family and probably be gone after a few generations. Like there are human families that are more likely to produce offspring with 6 digits on their hands, but since it isn’t more advantageous than 5 digits (6 digit people don’t produce more offspring and 5 digit people aren’t more likely to die before reaching reproductive maturity) that mutation doesn’t spread across the entire species. Sure if you could sample the genome of every human on earth and identify every advantageous gene mutation you could build the ultimate human DNA. But that’s artificially created, something like that will never happen through evolutionary pathways.
No.
No, you are 100% wrong.
no they’re not. by definition if you don’t have what you need you don’t survive. we definitively don’t need it. or at least haven’t for millions of years. that’s different from saying we wouldn’t benefit from it.
although that’s not a guarantee either. more information isn’t always better.
Okay true, but I still feel the comment was misleading. If it were phrased as “If vertebrae don’t have it, it means it wouldn’t improve their fitness” it would be wrong. I’ll admit that the comment as worded is true, but it does depend on a very literal interpretation of what “needs” means. Why even post that? In my opinion, that makes it low-quality content, so worth a downvote.
disagree. again, we don’t even know if such a change would be beneficial.
also, more importantly, the post is entirely stupid.
suboptimal by what measure? became disadvantageous how? against what? last time i checked ve**rtebrates were still dominating. now even more than they did during the ages of dinosaurs.
evolution was too late to correct it… what? first of all, is it even a mistake to correct? where’s the evidence of that? second of all, did evolution stop? too late how? it’s complete bullshit, and if anything the original comment wasn’t harsh enough on it.
I’m not claiming that this change in how eyes work would be an improvement. I’m claiming that the following does not hold generally: “Doesn’t have adaptation X ⇒ adaptation X would not improve fitness.”
yeah but that’s not part of the original comment, not even by implication. the opposite is also not true so it doesn’t factor in at all. even though you’re not claiming it would be an improvement the original post clearly does and that’s what the top level comment is countering.