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Interestingly written article. Raises some questions: >Newts with weaker poison? They get eaten. Snakes with less resistance? Have trouble finding newts the

Interestingly written article. Raises some questions: >Newts with weaker poison? They get eaten. Snakes with less resistance? Have trouble finding newts they can choke down, and don’t get to steal their poison. So the arms race continues. How does a snake know that the Newt has weaker/strong poison? Is it leaving some Newts along and eating others, or is it eating any Newt it runs across? Does a strong-poison newt survive snake consumption attempts?

calebkaiser 1y ago
I think the preceding sentence in that paragraph answers it. Important context here is that garter snakes tend to swallow prey whole. tldr: a strongly poisoned newt survives consumption attempts. > And it explains why the newts keep evolving to be more toxic: the snake may want to eat newts generally, but if an individual newt packs enough of a wallop, the snake may just retch it up and go after a different one. Newts with weaker poison? They get eaten. Snakes with less resistance? Have trouble finding newts they can choke down, and don’t get to steal their poison. So the arms race continues.
- thaumasiotes 1y ago
  > Snakes with less resistance? Have trouble finding newts they can choke down, and don’t get to steal their poison. That's got to be an extremely weak effect. No snake gets an individual benefit from eating the newts. They get a collective benefit, that predators recognize the species as poisonous, in which all snakes, poisonous and delicious alike, share equally. The problem is large enough that actually-poisonous animals routinely have delicious mimics of entirely different species who free-ride off of the work the originals do to be poisonous. You can't explain why snakes apparently need to avoid sending a dishonest signal with a theory that predicts that mimics don't exist.
  - calebkaiser 1y ago
    Yeah that particular aspect of his claim feels like the weakest. Here is a slightly more in-depth piece where a wildlife biologist mentions other possible forcing functions that cause the snakes to eat the newts: https://baynature.org/2022/04/06/the-bay-area-is-the-center-of-an-evolutionary-race-between-hungry-snakes-and-toxic-newts/ https://baynature.org/2022/04/06/the-bay-area-is-the-center-... From the article: > “When garter snakes are born in the late summer, they often live under mats of drying pond vegetation … That happens to be where the newly metamorphosed newts come out in the fall, and we suspect there could be a lot of interaction between predator and prey just because of this overlap in microenvironment. That could have led to strong selection in the past that resulted in such high levels of resistance.”
  - darkerside 1y ago
    > The problem is large enough that actually-poisonous animals routinely have delicious mimics of entirely different species who free-ride off of the work the originals do to be poisonous. When cargo culting goes right.
    - thaumasiotes 1y ago
      Yes, if supply planes couldn't tell the difference between military runways and cult runways, cargo cultists could lure them in and... depending on their defenses... overpower the pilot and take all the stuff.
  - the_af 1y ago
    Interesting. Let me see if I follow: once the snake population has the warning coloration, and predators know not to eat them, then individual snakes being successful at eating poisonous newts is unrelated to the snakes living long enough to pass their genes (i. e. being successful in terms of natural selection). So a snake which has the right colors will be successful, regardless of its diet. I wonder, is there a point where mimicry can fail? Can predators at some point start to eat the mimics?
    - catlifeonmars 1y ago
      I suspect that as the number of mimics increases (either an individual species or convergent evolution of mimicry, like we see with the number of insects with bee or wasp-like coloration), the relative risk of consuming things that look poisonous drops to a level where it’s sustainable for a population of predators. To your point I wonder if eventually some truly toxic species can become a victim of their own success
    - thaumasiotes 1y ago
      > Let me see if I follow: once the snake population has the warning coloration, and predators know not to eat them, then individual snakes being successful at eating poisonous newts is unrelated to the snakes living long enough to pass their genes (i. e. being successful in terms of natural selection). So a snake which has the right colors will be successful, regardless of its diet. Sort of. Whether the snake is poisonous is unrelated to its success, because it dies upon being eaten whether there are consequences to its predator or not. (The article takes some pains to show that this is untrue of the newts, but not the snakes.) However, > the snakes living long enough to pass their genes (i. e. being successful in terms of natural selection) This does not reflect a good understanding. Success means having more children, not having any children.
      - the_af 1y ago
        > This does not reflect a good understanding. Success means having more children, not having any children. I never said "any children", so your remark doesn't reflect a good understanding of what I wrote. Try not being pedantic for pedantry's sake, and engage with a question asked in good faith without playing games of one-upmanship.
riffraff 1y ago
it was mentioned elsewhere on the article that the snake may spit out the newt of it's too strong, kinda like a human with chili peppers, I suppose.
stevenwoo 1y ago
Maybe a better way to frame it is over time, there's some genetic sequence that gave the snake a preference for eating this newt in particular out of all potential prey and some other genetic sequence that gives them a bit of resistance so they can store the poison inside them. Those snakes that eat more of them with that genetic makeup, up to a point, are better able to reproduce. Run a few thousand years of iterations over this process, where the snake and newt are in a red queen situation, both running faster and faster just to keep up. It is possible to look at this as situation where neither the snake or newt is conscious of the choices or there is no ability to make decision, there is only following the built in behavior.
deleted 1y ago
[deleted]
kulahan 1y ago
I found this on Wikipedia, but tldr they taste test it. > Successful predation of the rough-skinned newt by the common garter snake is made possible by the ability of individuals in a common garter snake population to gauge whether the newt's level of toxin is too high to feed on. T. sirtalis assays toxin levels of the rough-skinned newt and decides whether or not the levels are manageable by partially swallowing the newt, and either swallowing or releasing the newt.

calebkaiser 1y ago

I think the preceding sentence in that paragraph answers it. Important context here is that garter snakes tend to swallow prey whole. tldr: a strongly poisoned newt survives consumption attempts. > And it explains why the newts keep evolving to be more toxic: the snake may want to eat newts generally, but if an individual newt packs enough of a wallop, the snake may just retch it up and go after a different one. Newts with weaker poison? They get eaten. Snakes with less resistance? Have trouble finding newts they can choke down, and don’t get to steal their poison. So the arms race continues.

thaumasiotes 1y ago
> Snakes with less resistance? Have trouble finding newts they can choke down, and don’t get to steal their poison. That's got to be an extremely weak effect. No snake gets an individual benefit from eating the newts. They get a collective benefit, that predators recognize the species as poisonous, in which all snakes, poisonous and delicious alike, share equally. The problem is large enough that actually-poisonous animals routinely have delicious mimics of entirely different species who free-ride off of the work the originals do to be poisonous. You can't explain why snakes apparently need to avoid sending a dishonest signal with a theory that predicts that mimics don't exist.
- calebkaiser 1y ago
  Yeah that particular aspect of his claim feels like the weakest. Here is a slightly more in-depth piece where a wildlife biologist mentions other possible forcing functions that cause the snakes to eat the newts: https://baynature.org/2022/04/06/the-bay-area-is-the-center-of-an-evolutionary-race-between-hungry-snakes-and-toxic-newts/ https://baynature.org/2022/04/06/the-bay-area-is-the-center-... From the article: > “When garter snakes are born in the late summer, they often live under mats of drying pond vegetation … That happens to be where the newly metamorphosed newts come out in the fall, and we suspect there could be a lot of interaction between predator and prey just because of this overlap in microenvironment. That could have led to strong selection in the past that resulted in such high levels of resistance.”
- darkerside 1y ago
  > The problem is large enough that actually-poisonous animals routinely have delicious mimics of entirely different species who free-ride off of the work the originals do to be poisonous. When cargo culting goes right.
  - thaumasiotes 1y ago
    Yes, if supply planes couldn't tell the difference between military runways and cult runways, cargo cultists could lure them in and... depending on their defenses... overpower the pilot and take all the stuff.
- the_af 1y ago
  Interesting. Let me see if I follow: once the snake population has the warning coloration, and predators know not to eat them, then individual snakes being successful at eating poisonous newts is unrelated to the snakes living long enough to pass their genes (i. e. being successful in terms of natural selection). So a snake which has the right colors will be successful, regardless of its diet. I wonder, is there a point where mimicry can fail? Can predators at some point start to eat the mimics?
  - catlifeonmars 1y ago
    I suspect that as the number of mimics increases (either an individual species or convergent evolution of mimicry, like we see with the number of insects with bee or wasp-like coloration), the relative risk of consuming things that look poisonous drops to a level where it’s sustainable for a population of predators. To your point I wonder if eventually some truly toxic species can become a victim of their own success
  - thaumasiotes 1y ago
    > Let me see if I follow: once the snake population has the warning coloration, and predators know not to eat them, then individual snakes being successful at eating poisonous newts is unrelated to the snakes living long enough to pass their genes (i. e. being successful in terms of natural selection). So a snake which has the right colors will be successful, regardless of its diet. Sort of. Whether the snake is poisonous is unrelated to its success, because it dies upon being eaten whether there are consequences to its predator or not. (The article takes some pains to show that this is untrue of the newts, but not the snakes.) However, > the snakes living long enough to pass their genes (i. e. being successful in terms of natural selection) This does not reflect a good understanding. Success means having more children, not having any children.
    - the_af 1y ago
      > This does not reflect a good understanding. Success means having more children, not having any children. I never said "any children", so your remark doesn't reflect a good understanding of what I wrote. Try not being pedantic for pedantry's sake, and engage with a question asked in good faith without playing games of one-upmanship.

riffraff 1y ago

it was mentioned elsewhere on the article that the snake may spit out the newt of it's too strong, kinda like a human with chili peppers, I suppose.

stevenwoo 1y ago

Maybe a better way to frame it is over time, there's some genetic sequence that gave the snake a preference for eating this newt in particular out of all potential prey and some other genetic sequence that gives them a bit of resistance so they can store the poison inside them. Those snakes that eat more of them with that genetic makeup, up to a point, are better able to reproduce. Run a few thousand years of iterations over this process, where the snake and newt are in a red queen situation, both running faster and faster just to keep up. It is possible to look at this as situation where neither the snake or newt is conscious of the choices or there is no ability to make decision, there is only following the built in behavior.

deleted 1y ago

[deleted]

kulahan 1y ago

I found this on Wikipedia, but tldr they taste test it. > Successful predation of the rough-skinned newt by the common garter snake is made possible by the ability of individuals in a common garter snake population to gauge whether the newt's level of toxin is too high to feed on. T. sirtalis assays toxin levels of the rough-skinned newt and decides whether or not the levels are manageable by partially swallowing the newt, and either swallowing or releasing the newt.