Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

How did two groups of fish separately evolve genes for making antifreeze?

theatlantic.com

Post reply on HN
Print view View original

31–39 of 39 posts

Re: How did two groups of fish separately evolve genes for making antifreeze?

#31

Post by everdrive »

bitL wrote: post #9
taneq wrote: post #6

From the headline I'd immediately guess many groups of fish were living in above-zero waters adjacent to sub-zero waters containing food. Eventually some of them experienced a random mutation which made them slightly less freezy and earned them free food! The account of the actual sequence of mutations required was really interesting, though. It's good to see an article go into that kind of detail!

Maybe the mutation wasn't really random? I wouldn't be surprised if at some point we find that the "90% unused brain capacity" is actually doing some long-term adaptation computations and then uses various signals to put that information into reproductive cells...

Then how do bacteria or plants evolve?

Re: How did two groups of fish separately evolve genes for making antifreeze?

#32

Post by LifeLiverTransp »

taneq wrote: post #6

From the headline I'd immediately guess many groups of fish were living in above-zero waters adjacent to sub-zero waters containing food. Eventually some of them experienced a random mutation which made them slightly less freezy and earned them free food! The account of the actual sequence of mutations required was really interesting, though. It's good to see an article go into that kind of detail!

My assumption would be that the pioneer species, trying to escape predation or searching for new niches open up the niche and then the foodchain follows the "lower" life forms, out of opportunity.

Re: How did two groups of fish separately evolve genes for making antifreeze?

#33

Post by [deleted] »

skywhopper wrote: post #5

Interesting article about some of the mechanics of DNA and evolution. But I wanted to call out a confusing use of the increasingly ambiguous word “partner” here: “There, she and her partner, Arthur DeVries, studied the notothens”. What sort of partner? Research partner, clearly. Oh, but with some googling you can find that they are married, so also romantic/life partner. I appreciate the sentiment behind the takeoff…

[deleted]

Re: How did two groups of fish separately evolve genes for making antifreeze?

#34

Post by Qwertystop »

Simon_says wrote: post #18
dmckeon wrote: post #7

Earlier quoted context omitted.

Why? This is science reporting, not tabloid journalism. We don’t need to know the marital status, gender preference, dietary restrictions, previous relationships, etc. Good writing about science is plenty. And “spouse” is a fine word if needed.

I agree with you, but then why bring it up at all?

They didn't bring it up.

> What sort of partner? Research partner, clearly.

The fact that the two happen also to be married need not be related to the use of the word.

Re: How did two groups of fish separately evolve genes for making antifreeze?

#35

Post by PhasmaFelis »

caprese wrote: post #11
bitL wrote: post #9

Earlier quoted context omitted.

Maybe the mutation wasn't really random? I wouldn't be surprised if at some point we find that the "90% unused brain capacity" is actually doing some long-term adaptation computations and then uses various signals to put that information into reproductive cells...

We are seeing external adaptive pressures that diminish natural selection as an absolute, such as in this paper https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4333222/ Its nice that science is able to adapt to new information. Natural selection needed to be an absolute to counter state-religion based spontaneous creation. But its now not an absolute, with worthwhile investigation of how life experience can make its way…

> We are seeing external adaptive pressures that diminish natural selection as an absolute, such as in this paper https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4333222/

That's still natural selection, it's just a different mechanism for it.

Re: How did two groups of fish separately evolve genes for making antifreeze?

#36

Post by caprese »

fifnir wrote: post #20
caprese wrote: post #13

Earlier quoted context omitted.

cited by 555 other papers suggesting RNA changes from life experience - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4333222/ so people are working on reproducing this and understanding this process more, to say more clearly: scientists are actively researching how evolution can happen without natural selection

Epigenetic research isn't going against evolution, it's refining some details. We are discovering some nonmendelian dynamics of inheritance, but being epigenetic they are only about how the organism can differentially use its genetic library.

was it not clear that I was talking about OP's claim regarding "natural selection outside of the body" when epigenetic is not outside of the body and can result in changes of the offspring, does your response run counter to my observation?

so far all the responses seem to be more about a semantical distinction of the word evolution and natural selection

Re: How did two groups of fish separately evolve genes for making antifreeze?

#37

Post by thaumasiotes »

cahooon wrote: post #28
thaumasiotes wrote: post #14

Earlier quoted context omitted.

> how evolution can happen without natural selection This sounds incoherent. What does "natural selection" mean to you?

Modern usage of “evolution” sometimes conflates “change of the organism over time or a lineage between generations” with “Darwinian selection”. Sexual selection is an easy example of evolution that’s not due to Darwinian “natural” selection.

Sexual selection is literally a textbook example of natural selection.

"Change of the organism between generations" is called "genetic drift" if it's undirected and "selection" if it's directed. The concept of "evolution without natural selection" doesn't really exist.

Selection is how you get organisms that appear to be designed for a purpose. Sexual attractiveness is a purpose.

Re: How did two groups of fish separately evolve genes for making antifreeze?

#38

Post by fifnir »

caprese wrote: post #36
fifnir wrote: post #20

Earlier quoted context omitted.

Epigenetic research isn't going against evolution, it's refining some details. We are discovering some nonmendelian dynamics of inheritance, but being epigenetic they are only about how the organism can differentially use its genetic library.

was it not clear that I was talking about OP's claim regarding "natural selection outside of the body" when epigenetic is not outside of the body and can result in changes of the offspring, does your response run counter to my observation? so far all the responses seem to be more about a semantical distinction of the word evolution and natural selection

Well semantics are important, especially in fields that someone is intimate with, and I'm currently finishing a phd in cis-regulation and epigenetics.

When we stress mice and notice a difference in their offspring through epigenetics, this is something that has already evolved in mice. Parts of the parental DNA get "marked" and the mark passes on to the offspring and influences their development, but the mechanism that connects external stress and the marking of the parental DNA is itself a genetic mechanism and subject to evolution.

The offspring whose development was changed because of the parental stress isn't evolved, much like a baby with FASD[1] isn't "evolved" either

[1]https://en.wikipedia.org/wiki/Fetal_alcohol_spectrum_disorde...

Re: How did two groups of fish separately evolve genes for making antifreeze?

#39

Post by caprese »

fifnir wrote: post #22
caprese wrote: post #11

Earlier quoted context omitted.

We are seeing external adaptive pressures that diminish natural selection as an absolute, such as in this paper https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4333222/ Its nice that science is able to adapt to new information. Natural selection needed to be an absolute to counter state-religion based spontaneous creation. But its now not an absolute, with worthwhile investigation of how life experience can make its way…

Maybe one day we can prove there's a teacup orbiting Saturn too !

maybe. the consequences being...?
Post reply on HN