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So this is interesting: It's not just the harsh environs of outer space that tardigrades can survive in. The little critters seem adept a

by revscat 12y ago

So this is interesting: It's not just the harsh environs of outer space that tardigrades can survive in. The little critters seem adept at living in some of the harshest regions of Earth. They have been discovered 5546m (18,196ft) up a mountain in the Himalayas, in Japanese hot springs, at the bottom of the ocean and in Antarctica. They can withstand huge amounts of radiation, being heated to 150 °C, and being frozen almost to absolute zero. I'm having a hard time seeing how the ability to survive in such high and low temperatures arose via natural selection, especially the ability to survive at near absolute zero while in the tun state. Such a condition obviously does not exist on Earth, so this feature could not have arisen via environmental pressures, at least not directly.

noir_lord 12y ago
> Such a condition obviously does not exist on Earth, so this feature could not have arisen via environmental pressures, at least not directly. Doesn't need to arise directly, it may be that the adaptations that allow you to survive -50C are the same ones that allow you to survive -200C. Also there is Exaptation where one trait for one set of circumstances later adapts to serve another set of circumstances - the classic been feathers, they evolved as a method of keeping warm and later where later co-opted for flight.
- revscat 12y ago
  This seems the most likely explanation, but it is still extraordinary. Being able to survive in cold is one thing. But being able to survive being placed in liquid nitrogen for an extended period of time? That's incredible.
  - civilian 12y ago
    I dunno, have you looked into the human suspended animation with sulphur? A layperson could say: "wow, it's amazing the humans adapted to go into suspended animation when exposed to the cold and an atmosphere of sulphur!" It's not really something we adapted to, it's just another accident of our biology. https://www.ted.com/talks/mark_roth_suspended_animation https://www.ted.com/talks/mark_roth_suspended_animation All life is a hack! All organisms are just pushing the minimum code change to get a leg up on everything else. Loopholes are everywhere.
  - Sharlin 12y ago
    Once you solve the problem of your cells freezing over, I don't think any additional cold is going to be much of a problem. If anything, the colder it is the better off you are due to the slowing of chemical reactions. There's a reason we freeze things to preserve them.
JackFr 12y ago
>Such a condition obviously does not exist on Earth, so this feature could not have arisen via environmental pressures, at least not directly. Your premise does not justify your conclusion. Reword your final sentence to read: Such a condition obviously does not exist on Earth, so this feature could not have arisen on Earth via environmental pressures, at least not directly.
IgorPartola 12y ago
What if the adaption is just a side-effect of another adaptation? As in, if there is no difference between surviving at -80 C and absolute 0? Besides, I don't exactly see a point in some intelligent creature creating these little buggers with the ability to survive basically anything, yet giving them no other purpose. It's the equivalent of creating a computer program that is in all ways perfect, yet does absolutely nothing.
- revscat 12y ago
  There is no intended implication for intelligence behind the extremophile behavior of tardigrades. Merely that it is curious how such a characteristic would have arisen given the absence of the environmental conditions (seemingly) needed to precipitate such traits.
  - IgorPartola 12y ago
    Fair enough. I still think that it's not that surprising. For example, nobody in the part of my ancestry that matters evolutionarily had to jump out of the way of a moving car, yet I am able to do this. Perhaps this analogy is too simplistic, but I think you see what I'm driving at.
    - yellowapple 12y ago
      "but I think you see what I'm driving at." Hah.
chm 12y ago
Have you read the entire article? They propose an explanation for this.
ChuckMcM 12y ago
They have been around a while, and the an evolutionary mechanism that lets you survived to -100C (some of the temperature extremes speculated in the last glacial period) might "just work" all the way down to near absolute zero. That said, I am surprised that no NFL team has picked the Tartigrade has their mascot/theme ("The Texas Tardigrades are victorious!" kinda rolls off the tongue and they the buggers are tough and hang in there, good qualities for a sports franchise) But the more interesting bit for me, is that they would survive on Mars if there are underground aquifers of liquid water occasionally, and Ganymede or any other moon with liquid seas if the radiation didn't kill them. Which I find interesting that we already have a 'proof of concept' of life that could be living off planet, now we need to figure out if it is actually out there.
- semi-extrinsic 12y ago
  As for the "Texas Tardigrades" proposal: the name sounds too much like "retard". Even if the local PC committee did not object, the opposing team supporters would have a field day.
Florin_Andrei 12y ago
We can also survive (sort of) open-floor offices and stuff like that, and we haven't evolved that capability.
judk 12y ago
The less you are made of, the less ways there are to break an important part of you. Complex organisms have many weaknesses.

by revscat 12y ago

noir_lord 12y ago

> Such a condition obviously does not exist on Earth, so this feature could not have arisen via environmental pressures, at least not directly. Doesn't need to arise directly, it may be that the adaptations that allow you to survive -50C are the same ones that allow you to survive -200C. Also there is Exaptation where one trait for one set of circumstances later adapts to serve another set of circumstances - the classic been feathers, they evolved as a method of keeping warm and later where later co-opted for flight.

revscat 12y ago
This seems the most likely explanation, but it is still extraordinary. Being able to survive in cold is one thing. But being able to survive being placed in liquid nitrogen for an extended period of time? That's incredible.
- civilian 12y ago
  I dunno, have you looked into the human suspended animation with sulphur? A layperson could say: "wow, it's amazing the humans adapted to go into suspended animation when exposed to the cold and an atmosphere of sulphur!" It's not really something we adapted to, it's just another accident of our biology. https://www.ted.com/talks/mark_roth_suspended_animation https://www.ted.com/talks/mark_roth_suspended_animation All life is a hack! All organisms are just pushing the minimum code change to get a leg up on everything else. Loopholes are everywhere.
- Sharlin 12y ago
  Once you solve the problem of your cells freezing over, I don't think any additional cold is going to be much of a problem. If anything, the colder it is the better off you are due to the slowing of chemical reactions. There's a reason we freeze things to preserve them.

JackFr 12y ago

>Such a condition obviously does not exist on Earth, so this feature could not have arisen via environmental pressures, at least not directly. Your premise does not justify your conclusion. Reword your final sentence to read: Such a condition obviously does not exist on Earth, so this feature could not have arisen on Earth via environmental pressures, at least not directly.

IgorPartola 12y ago

What if the adaption is just a side-effect of another adaptation? As in, if there is no difference between surviving at -80 C and absolute 0? Besides, I don't exactly see a point in some intelligent creature creating these little buggers with the ability to survive basically anything, yet giving them no other purpose. It's the equivalent of creating a computer program that is in all ways perfect, yet does absolutely nothing.

revscat 12y ago
There is no intended implication for intelligence behind the extremophile behavior of tardigrades. Merely that it is curious how such a characteristic would have arisen given the absence of the environmental conditions (seemingly) needed to precipitate such traits.
- IgorPartola 12y ago
  Fair enough. I still think that it's not that surprising. For example, nobody in the part of my ancestry that matters evolutionarily had to jump out of the way of a moving car, yet I am able to do this. Perhaps this analogy is too simplistic, but I think you see what I'm driving at.
  - yellowapple 12y ago
    "but I think you see what I'm driving at." Hah.

chm 12y ago

Have you read the entire article? They propose an explanation for this.

ChuckMcM 12y ago

They have been around a while, and the an evolutionary mechanism that lets you survived to -100C (some of the temperature extremes speculated in the last glacial period) might "just work" all the way down to near absolute zero. That said, I am surprised that no NFL team has picked the Tartigrade has their mascot/theme ("The Texas Tardigrades are victorious!" kinda rolls off the tongue and they the buggers are tough and hang in there, good qualities for a sports franchise) But the more interesting bit for me, is that they would survive on Mars if there are underground aquifers of liquid water occasionally, and Ganymede or any other moon with liquid seas if the radiation didn't kill them. Which I find interesting that we already have a 'proof of concept' of life that could be living off planet, now we need to figure out if it is actually out there.

semi-extrinsic 12y ago
As for the "Texas Tardigrades" proposal: the name sounds too much like "retard". Even if the local PC committee did not object, the opposing team supporters would have a field day.

Florin_Andrei 12y ago

We can also survive (sort of) open-floor offices and stuff like that, and we haven't evolved that capability.

judk 12y ago

The less you are made of, the less ways there are to break an important part of you. Complex organisms have many weaknesses.