Speed of adaptation....
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  1. #1
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    Default Speed of adaptation....

    It postulated to take forever for the natural evolution to change anything.

    Well, here again, a case showing the ongoing adaptation caused by rapidly changing environment.
    Just 250-300 years of industrial life-style already are showing profound affects on the human morphology (that's for a slow breeding mammalian species, not a bug).

    We can call this phenomenon "artificial selection" and qualify it as "reversible", if we so prefer.
    It's OK for better or for worse.

    Anyways, this thing is happening fast.
    Really fast.
    It does not take an evolution.

    ....over the last 250 years, our skulls have morphed in dangerous and troubling ways.
    https://onezero.medium.com/our-skull...s-f950faed696d
    Former "smoker boy". Classic, square 12 frame Dadants >> Long hive/Short frame/chemical-free experimentations.

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  3. #2
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    Default Re: Speed of adaptation....

    And a related article by a researcher I knew personally (just one of many his works).

    ....although in the initial phase of adaptation to any new factor the organism is close to the limits of its capacities, the manner in which it solves the problem is far from perfect. However, if the person or animal concerned survives, and the causal agent of adaptation continues to be active, the possibilities open to the organism increase and the extreme or urgent stage is replaced by one of effective, stable adaptation.
    https://www.questia.com/magazine/1G1...eme-conditions
    Former "smoker boy". Classic, square 12 frame Dadants >> Long hive/Short frame/chemical-free experimentations.

  4. #3
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    Default Re: Speed of adaptation....

    .
    As always Greg you are absolutely correct, and i have irrefutable proof of your concept.

    Last edited by Oldtimer; 09-23-2019 at 04:29 PM.
    "Every viewpoint, is a view from a point." - Solomon Parker

  5. #4
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    Default Re: Speed of adaptation....

    Took this cricket just 20 generations to evolve.

    https://www.nature.com/news/evolutio...ickets-1.15323

  6. #5
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    Default Re: Speed of adaptation....

    The article says "To protect themselves from their new enemy, large numbers of male crickets on the Hawaiian island of Kauai quickly stopped chirping".

    However that would be incorrect, and similar logic is often used in the beekeeping world.

    What would have really happened would have been that at least one individual with a non chirping mutation already existed. And once all the chirping individuals started to get eaten by the introduced predator, the feild was left open for the non chirping one.

    Had the predator not been introduced, the non chirping individual would have had little show of attracting a mate, and likely would have dissapeared from the population.

    One thing we learn from this, is that wether a mutation is good or bad, can depend on circumstances at the time. Which is why we do not necessarily want to eliminate any bee genetics even that sometimes seen as bad, or weak. Because if classic TF beekeeping lingo was applied to those crickets, the chirping ones would be referred to as "weak" and the non chirping ones as "survivors". But change the circumstances, ie, not have the predator, the reverse would be the case, the non chirping unable to attract a mate cricket would have been the "weak", and the chirping ones would have been the "survivors".
    "Every viewpoint, is a view from a point." - Solomon Parker

  7. #6
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    Default Re: Speed of adaptation....

    Quote Originally Posted by GregV View Post
    It postulated to take forever for the natural evolution to change anything.
    By whom? Scientists have been measuring the speed of evolution for over a century and have a pretty good idea of how fast it goes. New traits can emerge (or old traits disappear) in a small handful of generations - e.g. a century if your talking about elephants, an afternoon if talking about bacteria...

  8. #7
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    Default Re: Speed of adaptation....

    >What would have really happened would have been that at least one individual with a non chirping mutation already existed. And once all the chirping individuals started to get eaten by the introduced predator, the feild was left open for the non chirping one.

    This is exactly right. It's just selection.
    Michael Bush bushfarms.com/bees.htm "Everything works if you let it." ThePracticalBeekeeper.com 42y 40h 39yTF

  9. #8
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    Default Re: Speed of adaptation....

    Quote Originally Posted by Oldtimer View Post
    What would have really happened would have been that at least one individual with a non chirping mutation already existed. And once all the chirping individuals started to get eaten by the introduced predator, the feild was left open for the non chirping one.
    Right. The "weak" or "defective" cricket with mutated or improperly developed sounding spines perhaps saved the species. Whereas this cricket's lineage may have been bred out of existence over time due to their lack of ability to attract a mate, the environmental pressures radically changed, favoring the mutation. The favored trait of chirping became the weakness or the defect.

    This was not a learned adaptation by the cricket. The cricket now does not possess the hardware to actually make the sound. It was a physical trait that was brought forward through environmental pressures.

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    Default Re: Speed of adaptation....

    You cannot possibly generalise about adaptation in this way.

    The 'switching-off' of something which previously existed can be achieved relatively quickly and relatively easily - perhaps requiring just a single genetic mutation amongst the many dozens which could be involved in the development or operation of a particular organ.

    Contrast that with what would be required to create such an organ where nothing existed before: skeletal changes perhaps, certainly muscular and neuronal changes - all of which would take thousands of generations to accomplish, and during the process of which the organism must remain viable at each and every stage.

    There's 'switching something off' - which is fast; the modification of something which essentially already exists (colour, shape etc) which takes some time; and the creation of something new or of significant difference - which does indeed "take forever".
    LJ
    A Heretics Guide to Beekeeping http://heretics-guide.atwebpages.com/

  11. #10
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    Default Re: Speed of adaptation....

    Quote Originally Posted by little_john View Post
    ....There's 'switching something off' - which is fast; ....LJ
    Which in case of the bee very well may mean - switching OFF the recently and artificially selected in lack of defenses.
    The lack of defensiveness is not a norm.
    Sleepy and indifferent bees are not normal - they would normally get eaten by animals and preyed upon by multiple pests and parasites.

    If left alone, the defensiveness should return to pretty normal level pretty quickly (on different and various levels - against pests and/or against large predictors and/or whatever).
    Ideally, still manageable.

    PS: anyone seen this yet?
    I hanged it up for a reason..
    https://www.beesource.com/forums/sho...95#post1756795
    Former "smoker boy". Classic, square 12 frame Dadants >> Long hive/Short frame/chemical-free experimentations.

  12. #11
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    Default Re: Speed of adaptation....

    Quote Originally Posted by little_john View Post
    You cannot possibly generalise about adaptation in this way.
    I wasn't; I was talking about evolution, of which adaptation is one small part.

    Quote Originally Posted by little_john View Post
    The 'switching-off' of something which previously existed can be achieved relatively quickly and relatively easily - perhaps requiring just a single genetic mutation amongst the many dozens which could be involved in the development or operation of a particular organ.

    Contrast that with what would be required to create such an organ where nothing existed before: skeletal changes perhaps, certainly muscular and neuronal changes - all of which would take thousands of generations to accomplish, and during the process of which the organism must remain viable at each and every stage.
    Picking a new organ as a goal post is an odd choice for "new" evolution. Lots of traits that require something new can evolve quickly - antibiotic resistance genes, for example, can appear very quickly (a few to a few dozen generations).

    As for organs, they can and have evolved very quickly, because evolution isn't "dumb enough"* to do it from scratch. Organs typically evolve by duplication and modification (or straight modification) of existing organs. They also tend to evolve by parallel evolution and exaptation - e.g. multiple aspects evolving simultaneously in multiple "family lines", which are then brought together via mating, plus functional shifts of existing features. As one example, wall lizards were introduced onto Pod Kopiste island in 1971. By 2006 they had evolved two additional rudiment-like stomachs, allowing them to digest the tougher plants of Pod Kopiste. That's two - not one - new organs (plus 3 new coeceal valves) in 15 or 20 generations.

    Quote Originally Posted by little_john View Post
    There's 'switching something off' - which is fast; the modification of something which essentially already exists (colour, shape etc) which takes some time; and the creation of something new or of significant difference - which does indeed "take forever".
    LJ
    Except that it doesn't. Evolution goes at the speed it needs to, or the organism goes extinct.

  13. #12
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    Default Re: Speed of adaptation....

    It doesn't require a mutation. There were always crickets that chirped more or less or not at all. The ones not chirping at all were reproductively disadvantaged because they were not as good at finding a mate, so they were small in number. When chirping became a survival disadvantage, the ones tha chirped were eaten and the ones that did not chirp had more opportuinities to survive and mate. This is simply a shift in the population demographics, not a new mutation. The concept of evolution would require something NEW to happen through a mutation. There is nothing gained here. No evoluation has taken place. No mutation has taken place. Just a shift in population. That only takes a generation or two.
    Michael Bush bushfarms.com/bees.htm "Everything works if you let it." ThePracticalBeekeeper.com 42y 40h 39yTF

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    Default Re: Speed of adaptation....

    Quote Originally Posted by GregV View Post

    If left alone, the defensiveness should return to pretty normal level pretty quickly (on different and various levels - against pests and/or against large predictors and/or whatever).
    Ideally, still manageable.
    In this, I think of my bees as normal. They don't attack in large numbers, but they still have stingers and they haven't forgotten how to use them.

    Alex
    Ten years of Beekeeping before varroa. Started again spring of 2014.

  15. #14
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    Default Re: Speed of adaptation....

    Quote Originally Posted by Michael Bush View Post
    It doesn't require a mutation. There were always crickets that chirped more or less or not at all. The ones not chirping at all were reproductively disadvantaged because they were not as good at finding a mate, so they were small in number. When chirping became a survival disadvantage, the ones tha chirped were eaten and the ones that did not chirp had more opportuinities to survive and mate. This is simply a shift in the population demographics, not a new mutation. The concept of evolution would require something NEW to happen through a mutation. There is nothing gained here. No evoluation has taken place. No mutation has taken place. Just a shift in population. That only takes a generation or two.
    Michael, I agree with you, but I don't see the significant distinction you are making between this cricket and a slow evolution of any other species, other than there was a short cut.

    Take a breed of horses that live on the Serengeti, which dries up a million years ago (making all this up BTW). The horses do not grow longer necks to reach the higher vegetation. The horses that happen to be born with slightly longer necks breed more than the ones that don't, because they have better nutrition, live longer and therefore breed more. So a million years later, we have a giraffe-like horse creature. Whether this happens over a million years or over 20 years, does not mean one is evolution and the other is not.

    Also, we don't know that there was a cricket at the time of the arrival of the fly that was completely silent. Maybe some were merely quieter than others. As natural selection favored the quieter cricket, we now have a cricket that is physically different than the cricket that lived on the islands 20 years ago. That is evolution. Cornell University certainly described it as evolution.

  16. #15
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    Default Re: Speed of adaptation....

    Quote Originally Posted by SuiGeneris View Post
    I wasn't; I was talking about evolution, of which adaptation is one small part.
    But I was ('Speed of Adaptation' being the title of this thread). And my post wasn't directed at 'just you'.
    LJ
    A Heretics Guide to Beekeeping http://heretics-guide.atwebpages.com/

  17. #16
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    Default Re: Speed of adaptation....

    In natural selection, selection is factored with heritability. Negative selection (most bees die off) is influenced by very low heritability among the "survivors". Queens mate with 20-30 random drones and "crossing over (the reassortment of alleles in meiosis)" is higher in honeybees than in any other studied organism.

    Low heritability means the allele selected for is very unlikely to be present in the next generation, you can have decade after decade of selection and make no progress whatsoever. Low heritability conveys fitness to honey bees --- the bee is very slow to speciate, and doesn't specialize on a particular habitat or flower -- it remains a generalist.

    What we have (mostly) seen in honeybees is reversion to a feral form. As mortality has increased, the bees have optimized on a form that swarms more frequently (biased against the greater winter mortality of late swarms). Swarming tendency may simply mean selection of small nest sites, (a known genetic trait). We see bees that are more defensive ( *and* more likely to rob other hives) to reduce that cause of colony loss. In other words, the directed selection that made bees more domestic has been reversed in the promotion of "feral" traits. These crude advantages (swarmy, defensive bees) will overwhelm the highly fragile behaviors discovered by human breeders. Evolution is "lazy", and if there is a crude, ancestral trait (swarming to the limit of survival)-- the crude trait dominates in the genome selection, especially when heritabilty is low.

    The current party-line of the Ur-TF gurus (Solomon Parker and his kin) is "let them die". This is nothing more than a "death cult" -- and runs counter to hard, exacting work of isolating and promoting hygienic traits. Of course, Solomon lost his entire home apiary last winter, and announced he was off "swarm trapping". Which means, of course, an entire decade of selection was thrown away like so much rubbish. You are far more likely to make genetic progress with a "closed population model" system where you find and select the most favorable morphs and preserve their genetics (by any intervention necessary) while you deliberately cross-breed the favorable lines.

    The David Peck presentation at Apimondia found the survival traits in the "Arnot Forest" bees are less exactly expressed for VSH/brood removal than in deliberately (human managed) selection. The feral bees stopped short of the "human" selection (hypothetically due to 1) inability to maintain the trait in an open-mating environment, 2) excess culling by extreme VSH expression weakens the bees).

    The popular accounts of TF apiaries is "crash, followed by redemption". This story, while making good propaganda, cannot be true. Unless you live on a desert island, you must have high levels of continuing selection (colony culling) or the bees simply revert to the "feral" form (as shown by the Arnot Forest data, where wild bees stopped short) because out-crossing is required, and heritabilty is low. Any one promoting the "crash, followed by redemption" narrative is immediately suspect, in my mind, for fraud.

    I note the Kirk Webster "redemption" tale was properly criticized by folks from his territory as incomplete.

  18. #17
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    Default Re: Speed of adaptation....

    >Michael, I agree with you, but I don't see the significant distinction you are making between this cricket and a slow evolution of any other species, other than there was a short cut.

    All the difference in the world. Subraction is not at all the same as addition. If I have a gene pool that sometimes has a a trait and sometimes not, it is a simple matter for the ones with that trait (or without that trait) to be removed if it is no longer helpful to them. If I have a gene pool that does not have a trait, I cannot breed for it nor select for it. I have to wait forever for a lucky mutation. And forever is how long it will take... There is a lot of difference between forever and a couple of generations... Subtraction does not explain the complex and diverse species on this planet. Evolution tries to explain it by addition that comes from mutation. A very unlikely thing to happen even once...

    If I want horses with long necks I have to find horses with long necks first and then breed from them. I can't make horses have longer necks than is already in the gene pool.
    Michael Bush bushfarms.com/bees.htm "Everything works if you let it." ThePracticalBeekeeper.com 42y 40h 39yTF

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    Default Re: Speed of adaptation....

    Quote Originally Posted by Michael Bush View Post
    If I want horses with long necks I have to find horses with long necks first and then breed from them. I can't make horses have longer necks than is already in the gene pool.
    So, in your view, giraffes did not mutate. Each generation simply selected the longest necks of that generation ('ones with that trait') to propagate, correct? This occurs generation after generation and after a million years, the species that once had a 1 meter neck, now has a 5 meter neck. I understand your push back on my use of the word "mutation" above.

    But are you also saying that this is also not "evolution" either?

  20. #19
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    Default Re: Speed of adaptation....

    You can observe selection and it is ALWAYS subtraction. You are always removing the ones that either can't survive (natural selection) or don't meet your criteria (human selection). You can't add something that isn't there. That has never been observed so I think it is irrelevant to any practical discussion.
    Michael Bush bushfarms.com/bees.htm "Everything works if you let it." ThePracticalBeekeeper.com 42y 40h 39yTF

  21. #20
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    Default Re: Speed of adaptation....

    For our purposes AND such short-terms - the word "evolution" is hardly relevant.

    Yes - we always exist within the evolution context (or the Earth's geological time-frame, for that matter). What is the big deal there? This is very clear.

    No - no, we don't care much of those useless time frames (for our purposes).

    For our practical purposes, the time-frames are usually defined by a single human life.
    For our purposes, the adaptations indeed occur fast.
    Even a single organism adapts during its lifespan.
    I certainly have adapted and will continue (as a practicing athlete).
    A line of few consecutive organisms generations definitely is capable of adaptation required to survive (within the limits of the organism's available tools).
    Former "smoker boy". Classic, square 12 frame Dadants >> Long hive/Short frame/chemical-free experimentations.

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