6 ms·

"They're rather specialized, and there are lots of other jumpers that don't have them, so there must be some kind of advantage." Not necessarily. Evolution has

"They're rather specialized, and there are lots of other jumpers that don't have them, so there must be some kind of advantage." Not necessarily. Evolution has a lot to do with path dependence and in no way guarantees the best of all possible adaptations.

zdean 13y ago
Could you clarify/expound on this?
- robbiep 13y ago
  Perhaps the best option would be if you went out and grabbed a copy of 'Climbing mount improbable' - It will answer all your questions on this and then some
- jerf 13y ago
  Evolution works by incremental changes, each of which to a first approximation must be at least neutral and preferably advantageous to producing offspring. In order for evolution to get from A to B, there must be a path of incremental advantageous changes to get from here to there. It can't magically leap from one optimum to another. So you see things like the way the same basic body plan is reused endlessly in the natural world; with only incremental changes available to create the next species, you can't create a whole new body plan from scratch, even if it would be completely appropriate due to, say, transitioning from land to water. It is also completely goalless; if there is a fantastic two-gene change that a species could make, even if both are individually advantageous, there's no particular force that will cause them to occur [1]. Evolution is both very powerful, with many people underestimating it, and profoundly stupid, with many people also overestimating it. Once humans really get cracking with the gene engineering (which has proved harder than we had initially hoped, but I'm still confident we'll get there), I'm sure we'll find a plethora of relatively simple changes we can make to natural organisms that may involve changing three or four genes simultaneously where no single change is advantageous, which is a thing that evolution essentially can't do. [1]: Or at least, not yet... one bizarre-ish, "Selfish Gene" way of looking at human gene engineering is evolution evolving itself a way to make those multi-gene changes. Still not in a directed fashion, of course. But evolution will still apply to our own gene engineered creations, just possibly with a very different set of constraints, such as potentially severing the billion-year-old connection between fitness and direct biological reproduction... as I've said on HN before, you don't have to be a full-on "Rapture of the Nerds"-style Singulatarian to see that the future may get very weird....
  - bernardom 13y ago
    Whoa. That blew my mind. So we're evolving in such a way to be able to make combinatorial multi-gene changes- by evolving brains big enough to be able to develop gene engineering?
    - jerf 13y ago
      Remember, it's not directed. Evolution qua evolution hasn't got a problem going to the brink, then watching humanity wipe out, then never building another intelligent species on Earth again... of course it doesn't have a problem, since it isn't a human or even a living thing that could have a problem, or indeed have anything. But observationally, humanity is currently in a place where that level of gene engineering is a decent bet, yes.
    - ams6110 13y ago
      But the jury is still out on whether that ability is a net positive for our survival in evolutionary terms. And if it isn't, well, natural selection is quite merciless.
    - jk4930 13y ago
      There's another term from the mentioned "Selfish Gene" (which is a book by the same title): https://en.wikipedia.org/wiki/Memetics https://en.wikipedia.org/wiki/Memetics It's a view on how ideas spread and use hosts (e.g., human brains) as carriers. They mutate, they're selected, they compete for "brain space". One funny perspective is that we're the slaves to genes and memes, both using us to survive. We're just carrying out their orders. :) (In the end it's just a way to look at information diffusion with focus on the way how ideas replicate and the condition of their success or failure over time, abstracting away from social/cultural context and other hard to grasp things.)
      - upquark 13y ago
        Wouldn't it be in the best interest of memes to never let us figure them out though? To never obtain this view of the world where memes are exposed for the parasites that they are? Maybe "theory of memetics" is a next-generation meme that took over our collective consciousness to exterminate all the other primitive memes and gain world domination :)
- nialo 13y ago
  The simple way to see this is that evolution is essentially just the simplest possible hill climbing algorithm (at each step, change one random gene on some fraction of organisms in a random way, keep the best set of genes for the next step). It can do amazing things, but only because it's had millions/billions of years and an entire planet to run on.
muyuu 13y ago
Almost every complex AND specialized adaptation has an advantage. In this case it seems pretty obvious that gears can be better than friction at transmitting torque.
- thwest 13y ago
  > every complex AND specialized adaptation The ones that stay around long enough to be studied perhaps.
- possibilistic 13y ago
  I don't think you can really get away with saying that. I think a better phrasing would be, "the summation of all adaptations in addition to environmental state (including benefits or constraints to itself and all others) has led to the survival in its present environment". It's really about optimization gradients in a particular time/environmental/social niche. Everything can change with the purturbation of any factor--but that's evolution for you. Adative curve fitting.
  - muyuu 13y ago
    You (and the other posted) have conveniently ignored the word "almost" in my post.
- javajosh 13y ago
  Acne in adolescent humans is fairly complex, specialized, and life-cycle limited, like the insect gears, but acne doesn't appear to offer teens any advantage. Acne is just ..collateral from another (beneficial) process. Those gears are probably the same thing.
smosher 13y ago
I wonder whether you're responding to the the journalist or the person they're quoting. If you read the rest of the article, that idea does become more compelling since the creature loses those gears at its final stage in life.
bnegreve 13y ago
Isn't this the advantage?: > Larger animals, whether kangaroos or NBA players, rely on their nervous system to keep their legs in sync when pushing off to jump—using a constant loop of adjustment and feedback. But for the issus, their legs outpace their nervous system. By the time the insect has sent a signal from its legs to its brain and back again, roughly 5 or 6 milliseconds, the launch has long since happened. Instead, the gears, which engage before the jump, let the issus lock its legs together—synchronizing their movements to a precision of 1/300,000 of a second.
- samolang 13y ago
  Did you read the whole article? The article clearly states that the same thing can be accomplished using friction instead of gears (as it is in a bunch of organisms and the adult version of this organism).
  - bnegreve 13y ago
    No, I actually skimmed through it, hence my (genuine) question. Anyway, thanks for the answer.

zdean 13y ago

Could you clarify/expound on this?

robbiep 13y ago
Perhaps the best option would be if you went out and grabbed a copy of 'Climbing mount improbable' - It will answer all your questions on this and then some
jerf 13y ago
Evolution works by incremental changes, each of which to a first approximation must be at least neutral and preferably advantageous to producing offspring. In order for evolution to get from A to B, there must be a path of incremental advantageous changes to get from here to there. It can't magically leap from one optimum to another. So you see things like the way the same basic body plan is reused endlessly in the natural world; with only incremental changes available to create the next species, you can't create a whole new body plan from scratch, even if it would be completely appropriate due to, say, transitioning from land to water. It is also completely goalless; if there is a fantastic two-gene change that a species could make, even if both are individually advantageous, there's no particular force that will cause them to occur [1]. Evolution is both very powerful, with many people underestimating it, and profoundly stupid, with many people also overestimating it. Once humans really get cracking with the gene engineering (which has proved harder than we had initially hoped, but I'm still confident we'll get there), I'm sure we'll find a plethora of relatively simple changes we can make to natural organisms that may involve changing three or four genes simultaneously where no single change is advantageous, which is a thing that evolution essentially can't do. [1]: Or at least, not yet... one bizarre-ish, "Selfish Gene" way of looking at human gene engineering is evolution evolving itself a way to make those multi-gene changes. Still not in a directed fashion, of course. But evolution will still apply to our own gene engineered creations, just possibly with a very different set of constraints, such as potentially severing the billion-year-old connection between fitness and direct biological reproduction... as I've said on HN before, you don't have to be a full-on "Rapture of the Nerds"-style Singulatarian to see that the future may get very weird....
- bernardom 13y ago
  Whoa. That blew my mind. So we're evolving in such a way to be able to make combinatorial multi-gene changes- by evolving brains big enough to be able to develop gene engineering?
  - jerf 13y ago
    Remember, it's not directed. Evolution qua evolution hasn't got a problem going to the brink, then watching humanity wipe out, then never building another intelligent species on Earth again... of course it doesn't have a problem, since it isn't a human or even a living thing that could have a problem, or indeed have anything. But observationally, humanity is currently in a place where that level of gene engineering is a decent bet, yes.
  - ams6110 13y ago
    But the jury is still out on whether that ability is a net positive for our survival in evolutionary terms. And if it isn't, well, natural selection is quite merciless.
  - jk4930 13y ago
    There's another term from the mentioned "Selfish Gene" (which is a book by the same title): https://en.wikipedia.org/wiki/Memetics https://en.wikipedia.org/wiki/Memetics It's a view on how ideas spread and use hosts (e.g., human brains) as carriers. They mutate, they're selected, they compete for "brain space". One funny perspective is that we're the slaves to genes and memes, both using us to survive. We're just carrying out their orders. :) (In the end it's just a way to look at information diffusion with focus on the way how ideas replicate and the condition of their success or failure over time, abstracting away from social/cultural context and other hard to grasp things.)
    - upquark 13y ago
      Wouldn't it be in the best interest of memes to never let us figure them out though? To never obtain this view of the world where memes are exposed for the parasites that they are? Maybe "theory of memetics" is a next-generation meme that took over our collective consciousness to exterminate all the other primitive memes and gain world domination :)
nialo 13y ago
The simple way to see this is that evolution is essentially just the simplest possible hill climbing algorithm (at each step, change one random gene on some fraction of organisms in a random way, keep the best set of genes for the next step). It can do amazing things, but only because it's had millions/billions of years and an entire planet to run on.

muyuu 13y ago

Almost every complex AND specialized adaptation has an advantage. In this case it seems pretty obvious that gears can be better than friction at transmitting torque.

thwest 13y ago
> every complex AND specialized adaptation The ones that stay around long enough to be studied perhaps.
possibilistic 13y ago
I don't think you can really get away with saying that. I think a better phrasing would be, "the summation of all adaptations in addition to environmental state (including benefits or constraints to itself and all others) has led to the survival in its present environment". It's really about optimization gradients in a particular time/environmental/social niche. Everything can change with the purturbation of any factor--but that's evolution for you. Adative curve fitting.
- muyuu 13y ago
  You (and the other posted) have conveniently ignored the word "almost" in my post.
javajosh 13y ago
Acne in adolescent humans is fairly complex, specialized, and life-cycle limited, like the insect gears, but acne doesn't appear to offer teens any advantage. Acne is just ..collateral from another (beneficial) process. Those gears are probably the same thing.

smosher 13y ago

I wonder whether you're responding to the the journalist or the person they're quoting. If you read the rest of the article, that idea does become more compelling since the creature loses those gears at its final stage in life.

bnegreve 13y ago

Isn't this the advantage?: > Larger animals, whether kangaroos or NBA players, rely on their nervous system to keep their legs in sync when pushing off to jump—using a constant loop of adjustment and feedback. But for the issus, their legs outpace their nervous system. By the time the insect has sent a signal from its legs to its brain and back again, roughly 5 or 6 milliseconds, the launch has long since happened. Instead, the gears, which engage before the jump, let the issus lock its legs together—synchronizing their movements to a precision of 1/300,000 of a second.

samolang 13y ago
Did you read the whole article? The article clearly states that the same thing can be accomplished using friction instead of gears (as it is in a bunch of organisms and the adult version of this organism).
- bnegreve 13y ago
  No, I actually skimmed through it, hence my (genuine) question. Anyway, thanks for the answer.