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Maybe we should use the word "use unknown" instead of "useless" when dealing with things we don't fully understand. History has humbled us countless times. I r

by umvi 5y ago

Maybe we should use the word "use unknown" instead of "useless" when dealing with things we don't fully understand. History has humbled us countless times. I recall a recent Veritasium video wherein famous mathematicians of centuries past labelled the concept of negative numbers "useless" (because they didn't understand how they could be useful). My high school bio teacher confidently claimed that the appendix was a "useless organ".

bruce343434 5y ago
The video in question, for those curious: https://www.youtube.com/watch?v=cUzklzVXJwo https://www.youtube.com/watch?v=cUzklzVXJwo
gus_massa 5y ago
I agree, but note that the title of the research article is "Microchromosomes are building blocks of bird, reptile, and mammal chromosomes".
ConcernedCoder 5y ago
It is difficult to imagine a system of evolution where "useless" survives in successful iterations.
- enkid 5y ago
  Certainly there are thing that formerly had a use but are less useful now. I'd be careful calling something useless, but if there isn't an advantage to getting rid of a feature, I see no reason it would be gotten rid of.
- epistasis 5y ago
  Your point of view in evolution is called Adaptionism, but there are those who believe otherwise, and use the term "spandrel" to talk about the "useless" things that evolution carries along. https://en.m.wikipedia.org/wiki/Spandrel_(biology) https://en.m.wikipedia.org/wiki/Spandrel_(biology) Of course, something that is currently useless may become useful as the environment changes. Or it may not. Personally, I find a healthy sense of detachment from purpose, and certainly from any sort of teleology, is necessary to become philosophically consistent with the evidence from evolutionary biology.
  - ConcernedCoder 5y ago
    Thanks for the rabbit hole ( I've never really studied evolution outside of CS applications ). Your point of view about detachment makes quite a bit of sense to me, and if the spandrel idea proves true I guess we (Homo sapiens) will just have to take it on the chin...
  - elliekelly 5y ago
    This is quite interesting! Thanks for sharing! So might it be that a species, as a whole, benefits from carrying around a certain amount of “spandrels”? A genetic insurance policy of sorts to protect against/quickly adapt to unforeseen changes? Has there been any research into the prevalence (or absence) of spandrels in species that have gone extinct?
    - epistasis 5y ago
      I'm not sure if there's much research in evolution about species that have gone extinct versus extant species, or at least I haven't encountered it. The human genome carries around a massive amount of spandrels, in the form of what is called "selfish DNA." About 15% of the human genome consists of repeats of a single sequence: the Alu gene, which seems to primarily exist to replicate itself in the genome. This is part of a class of genes called transposable elements: https://en.m.wikipedia.org/wiki/Transposable_element https://en.m.wikipedia.org/wiki/Transposable_element And when discovered in corn, accounted for 85% of the genome. Barbara McClintock, their discoverer, hypothesized that they serve as a growth bed for evolution. And over the years it has indeed been found that individual transposable elements can serve as the seeds for new control sequences that coordinate when to turn genes on and off. The major forces of evolution in vertebrates are not big changes in proteins, but rather changes in when and how various proteins get activated, and transposable elements serve a big function in allowing that sort of evolutionary change in genomic sequences. Does most repetitive DNA in the genome seem to be useless, in that its deletion or replacement have little effect on the genome? Probably! But all that fluff also facilitates more easy rearrangement of the genome, because if every part of the genome was essential, randomly moving a chunk of DNA into a new spot would likely kill off some useful stuff. But if there's a bunch of stuff that is useless, randomly copying some stuff into a random spot is less likely to disrupt something. If the genome is a hard drive, there's no "free list" or file system for the genome, so random writes are less likely to be disastrous if there's nothing of importance on most of the drive. I used to get upset at the term "junk DNA" but I don't really care one way or the other now. One cell's junk is another's treasure.
- BurningFrog 5y ago
  I find it difficult to imagine a system of evolution where useless code is reliably removed.
  - baruch 5y ago
    Presumably there is a cost to carrying the DNA, if it gets removed by chance and the cost was high enough the useless part will disappear. That however hinges on the cost being high enough, if the cost is negligible then there is no real pressure either way.
    - dekhn 5y ago
      this cost of "DNA size" is a long and ongoing argument in biology with no clear answer. Here's the strongest straw man argument in favor of "there are large amounts of non-funcitonal DNA which has zero evolutionary cost": https://www.cell.com/current-biology/pdf/S0960-9822(12)01154-2.pdf https://www.cell.com/current-biology/pdf/S0960-9822(12)01154...
- nextaccountic 5y ago
  It depends on the cost of carrying vestigial stuff around vs the time required to make such changes (thousands of years? millions of years?) Sometimes organisms carry things not very useful anymore for a looong time.
- roywiggins 5y ago
  Evolution is not that ruthless. Useless but neutral traits can just stick around, if there's no selection pressure to get rid of them.
awillen 5y ago
It looks like the only person who described them as useless is the editor who wrote the headline, and they did it in an incredibly disingenuous (and grammatically incorrect way) by putting quotes around it. That implies that someone in the study used the word useless, which doesn't actually appear to be the case.
jfrunyon 5y ago
> My high school bio teacher confidently claimed that the appendix was a "useless organ". So does the Encyclopedia Brittanica, Healthline, and any number of other sources: > appendix, formally vermiform appendix, in anatomy, a vestigial hollow tube
- echelon 5y ago
  If the appendix truly serves no function and isn't developmentally required, then selection pressures would tend to remove it. It likely has some complex purpose, such as a reservoir for microbiome.
  - theshrike79 5y ago
    The appendix is used to reboot the intestinal biome in case of a catastrophic event. It's pretty much an on-site backup for intestinal flora :)
  - beebmam 5y ago
    This is a common misunderstanding. The same logic would apply to male nipples. It's a flawed logic.
    - wwwwewwww 5y ago
      Nipples are used by female mammals for feeding their young, so this logic does not apply to nipples.
      - beebmam 5y ago
        It certainly does apply: why do men have nipples? Likely for reasons similar to why we have an appendix. Fundamentally, natural selection and evolution are models that help explain general biological processes, to help us comprehend a bigger picture. Around the edges of that picture, it's not fully clear. The truth is that the universe is governed by laws that are deeply unintuitive: general relativity and the standard model. Each layer of abstraction on these makes the periphery of the image fuzzier, but allows us to make more sense of the part of the image that we're focusing in on.
OneLeggedCat 5y ago
The first sentence of the article: "Originally, they were thought to be just specks of dust on a microscope slide."
deleted 5y ago
[deleted]
micromacrofoot 5y ago
not to mention the perception of some organisms in ecosystems as "useless" only to discover their absence causes the system to collapse
samus 5y ago
To their limited knowledge, it was indeed useless. Scientist can make such statements if they feel up to, but they must also have the humility to later eat their own words when they are proven wrong.

by umvi 5y ago

bruce343434 5y ago

The video in question, for those curious: https://www.youtube.com/watch?v=cUzklzVXJwo https://www.youtube.com/watch?v=cUzklzVXJwo

gus_massa 5y ago

I agree, but note that the title of the research article is "Microchromosomes are building blocks of bird, reptile, and mammal chromosomes".

ConcernedCoder 5y ago

It is difficult to imagine a system of evolution where "useless" survives in successful iterations.

enkid 5y ago
Certainly there are thing that formerly had a use but are less useful now. I'd be careful calling something useless, but if there isn't an advantage to getting rid of a feature, I see no reason it would be gotten rid of.
epistasis 5y ago
Your point of view in evolution is called Adaptionism, but there are those who believe otherwise, and use the term "spandrel" to talk about the "useless" things that evolution carries along. https://en.m.wikipedia.org/wiki/Spandrel_(biology) https://en.m.wikipedia.org/wiki/Spandrel_(biology) Of course, something that is currently useless may become useful as the environment changes. Or it may not. Personally, I find a healthy sense of detachment from purpose, and certainly from any sort of teleology, is necessary to become philosophically consistent with the evidence from evolutionary biology.
- ConcernedCoder 5y ago
  Thanks for the rabbit hole ( I've never really studied evolution outside of CS applications ). Your point of view about detachment makes quite a bit of sense to me, and if the spandrel idea proves true I guess we (Homo sapiens) will just have to take it on the chin...
- elliekelly 5y ago
  This is quite interesting! Thanks for sharing! So might it be that a species, as a whole, benefits from carrying around a certain amount of “spandrels”? A genetic insurance policy of sorts to protect against/quickly adapt to unforeseen changes? Has there been any research into the prevalence (or absence) of spandrels in species that have gone extinct?
  - epistasis 5y ago
    I'm not sure if there's much research in evolution about species that have gone extinct versus extant species, or at least I haven't encountered it. The human genome carries around a massive amount of spandrels, in the form of what is called "selfish DNA." About 15% of the human genome consists of repeats of a single sequence: the Alu gene, which seems to primarily exist to replicate itself in the genome. This is part of a class of genes called transposable elements: https://en.m.wikipedia.org/wiki/Transposable_element https://en.m.wikipedia.org/wiki/Transposable_element And when discovered in corn, accounted for 85% of the genome. Barbara McClintock, their discoverer, hypothesized that they serve as a growth bed for evolution. And over the years it has indeed been found that individual transposable elements can serve as the seeds for new control sequences that coordinate when to turn genes on and off. The major forces of evolution in vertebrates are not big changes in proteins, but rather changes in when and how various proteins get activated, and transposable elements serve a big function in allowing that sort of evolutionary change in genomic sequences. Does most repetitive DNA in the genome seem to be useless, in that its deletion or replacement have little effect on the genome? Probably! But all that fluff also facilitates more easy rearrangement of the genome, because if every part of the genome was essential, randomly moving a chunk of DNA into a new spot would likely kill off some useful stuff. But if there's a bunch of stuff that is useless, randomly copying some stuff into a random spot is less likely to disrupt something. If the genome is a hard drive, there's no "free list" or file system for the genome, so random writes are less likely to be disastrous if there's nothing of importance on most of the drive. I used to get upset at the term "junk DNA" but I don't really care one way or the other now. One cell's junk is another's treasure.
BurningFrog 5y ago
I find it difficult to imagine a system of evolution where useless code is reliably removed.
- baruch 5y ago
  Presumably there is a cost to carrying the DNA, if it gets removed by chance and the cost was high enough the useless part will disappear. That however hinges on the cost being high enough, if the cost is negligible then there is no real pressure either way.
  - dekhn 5y ago
    this cost of "DNA size" is a long and ongoing argument in biology with no clear answer. Here's the strongest straw man argument in favor of "there are large amounts of non-funcitonal DNA which has zero evolutionary cost": https://www.cell.com/current-biology/pdf/S0960-9822(12)01154-2.pdf https://www.cell.com/current-biology/pdf/S0960-9822(12)01154...
nextaccountic 5y ago
It depends on the cost of carrying vestigial stuff around vs the time required to make such changes (thousands of years? millions of years?) Sometimes organisms carry things not very useful anymore for a looong time.
roywiggins 5y ago
Evolution is not that ruthless. Useless but neutral traits can just stick around, if there's no selection pressure to get rid of them.

awillen 5y ago

It looks like the only person who described them as useless is the editor who wrote the headline, and they did it in an incredibly disingenuous (and grammatically incorrect way) by putting quotes around it. That implies that someone in the study used the word useless, which doesn't actually appear to be the case.

jfrunyon 5y ago

> My high school bio teacher confidently claimed that the appendix was a "useless organ". So does the Encyclopedia Brittanica, Healthline, and any number of other sources: > appendix, formally vermiform appendix, in anatomy, a vestigial hollow tube

echelon 5y ago
If the appendix truly serves no function and isn't developmentally required, then selection pressures would tend to remove it. It likely has some complex purpose, such as a reservoir for microbiome.
- theshrike79 5y ago
  The appendix is used to reboot the intestinal biome in case of a catastrophic event. It's pretty much an on-site backup for intestinal flora :)
- beebmam 5y ago
  This is a common misunderstanding. The same logic would apply to male nipples. It's a flawed logic.
  - wwwwewwww 5y ago
    Nipples are used by female mammals for feeding their young, so this logic does not apply to nipples.
    - beebmam 5y ago
      It certainly does apply: why do men have nipples? Likely for reasons similar to why we have an appendix. Fundamentally, natural selection and evolution are models that help explain general biological processes, to help us comprehend a bigger picture. Around the edges of that picture, it's not fully clear. The truth is that the universe is governed by laws that are deeply unintuitive: general relativity and the standard model. Each layer of abstraction on these makes the periphery of the image fuzzier, but allows us to make more sense of the part of the image that we're focusing in on.

OneLeggedCat 5y ago

The first sentence of the article: "Originally, they were thought to be just specks of dust on a microscope slide."

deleted 5y ago

[deleted]

micromacrofoot 5y ago

not to mention the perception of some organisms in ecosystems as "useless" only to discover their absence causes the system to collapse

samus 5y ago

To their limited knowledge, it was indeed useless. Scientist can make such statements if they feel up to, but they must also have the humility to later eat their own words when they are proven wrong.