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Comment by Mikeb85 | Hacker News Reader

It's not like battery acid is dissolving their shells. The ocean's PH is at around 8.1 which means it's alkaline, not acidic. These creatures rely on calcification for creating their shells, so it's that process which is being disrupted (the article does briefly mention that in between the scary headline and other scary/incorrect assertions).

Plenty of bivalves and shellfish live in fresh water which has significantly lower PH levels (more like 7-7.5) and survive so this isn't some harbinger of the apocalypse, but it is change nonetheless.

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Freshwater animals aren't really relevant since they aren't going to do any good for life in the ocean if the animals that evolved for PH of 8.1 can't survive due to decreasing alkalinity. If the ocean life can't adapt it very well could be a harbinger of the apocalypse. Not saying it will, but your assertion that it isn't is also a false bromide.

I'm going to go out on a limb and say that since life has existed on earth for quite some time, through changing conditions (CO2 levels were far, far higher at one point in earth's existence!) and in many different biomes, life will continue to exist. In fact, I wouldn't be surprised if in ~20 years we find that these crabs, through natural selection, manage to keep their shells or adapt through some other means.

The amount of time given to adapt to those changes seems likely to have a big effect on how well organisms weather them... just because the same conditions existed x million years ago doesn’t mean that life can deal with it if the same change happens over 100 years.

The rate of ecological collapse far outpaces most organisms ability to evolve.

Does it? Normally I hate to be the guy to ask for some sort of citation but on this subject, all I hear is doom and gloom yet none of the dire predictions ever come to fruition.

Aren't we currently living through a mass extinction? That seems like a reasonable proxy for "outpaces most organisms ability to evolve."

https://en.wikipedia.org/wiki/Holocene_extinction

That article defines a "mass extinction event" as 75% of species dying off within a specific timeframe, but then goes on to say that 50% of species might be extinct by the end of the century. Later it says 7% of species have gone extinct. Far cry from 75%.

The end of the centuary is only 80 years away, or ~4 human gereations. There are humans alive today that will experience it. In geological time, that is practically nothing.

The artivle you are refring to also says that the current rate of extinction is 10-100x that if previus mass extinctions. Unless you have some reason to believe we will manage to stop the ongoing ectinction event, then it will be a mass extinction by the time it is done; hence saying that we are in it.

What kind of timeframe do you imagine they mean?

There have been times when almost all life on earth died out. So like, yes we will continue to having living things on earth probably until it's swallowed by the sun, but that doesn't mean that it will remain habitable for any of the species that currently live here, including ourselves.

It's true that life has existed for a long time and survived a number of mass die-offs, but humans have only been around for a tiny sliver of that time.

So yeah, it's unlikely that humans could kill off all life on earth even if we keep trying to do so, but it's certainly possible that they'll cause their own destruction.

I think it's unlikely that human activity will lead to mass die-offs (of humans, we're already in a mass extinction event of animals) but our children and grandchildren may be in for a big lifestyle change.

"Life" will, but then this statement would have given false comfort to organisms watching the coming Oxygen catastrophe.

Earth has also undergone at least five mass extinction events that killed between 70-98% of life on the planet. Rapid changes in atmospheric conditions are not friendly to life. Life is not robust or particularly adaptable at the species level, or on non-geological timescales.

You went too far on that limb.

The ocean Ph level doesn't have much to do with CO2 levels. It has everything to do with the rate of change of CO2 levels.

If you raise the CO2 level fast, the ocean turns acidic. If you raise it slowly, deposits of lime on the bottom of the ocean dissolve and Ph remains constant.

While CO2 has been much higher than the present, the rate of change is unprecedented.

Also evolution is a lot slower than you think. A change in Ph over millions of years could readily be adapted to by evolution. Over 20, not so much.

Evolution through natural selection happens much quicker than that. Sure, fish walking on land progression takes awhile, but otherwise it's pretty quick. https://www.sciencemag.org/news/2019/05/evolution-brings-ext...

As for the crabs, some of them still develop hard shells. They'll reproduce and the soft-shelled ones won't. So whatever it is that causes harder shells will persist.

Evolution has a fast mode and a slow mode.

The fast mode is that if there is enough genetic diversity in the population that a subset have a combination of traits that suffices, natural selection quickly will reduce the genetic diversity and all of the survivors will have those traits. The advantage of sexual reproduction is that much of the genetic diversity is retained and gets to recombine in interesting ways allowing the next challenge to be addressed.

The slow mode is that if overcoming a barrier requires random mutations to produce new traits, it takes many generations for that to happen.

The current pH allows some to survive and others not to. But with projected future pH levels, none will be able to survive. Therefore natural selection will select out the entire population as there isn't enough time for a new set of traits to evolve.

What about nylonase?

The rate of potential mutation in a species is tied to the reproduction rate.

Evolution in bacteria can therefore happen much more quickly than in larger organisms. Evolution in viruses is quicker still. (The flu that comes around each year is noticeably evolved from last year's one. In particular it is bred to avoid triggering immune system responses to recent flu variants.)

Crabs can't evolve at anything like the rate of bacteria.

So you predict extinction instead of adaptation or rather speciation (new cell lines resilient in a new environment which form a distinctly new genome)?

On current projections of ocean acidification, extinction is inevitable for this type of crab.

The only news here is that they have actually been measured to be impacted at rates that they were predicted to be impacted. The overall conclusion of what will happen is not changed.

This is where I would disagree with your belief that mutations are caused by replication rates rather than environmental feedback responses. The bandwidth of environmental sampling of larger species such as these crabs permits greater adaptability in near-future generations. I speak specifically to metabolizing de novo proteins in this novel environment which promote cellular replication stability, ie survival, eg enteric coatings.

I think you presuppose climate change is a disaster in your extinction judgment rather than a transient response to human industrialization.

Life on Earth had survived many much more dramatic events. Some had caused mass extinctions, but those organisms that survived soon captured the planet and thrived in a vacated environment.

What I'm really worried about is that future brings us much more severe issues to deal with, which no multicellular life can survive. [1] The problem is quite urgent, and we only have 500M-1B years to deal with this.

[1]: https://en.m.wikipedia.org/wiki/Timeline_of_the_far_future

In theory you are right, in practice threatened and endangered species may not have the population diversity for selective pressure to outpace population decline.

Thanx Mikeb85 , I was asking myself: "am I mad ?" as 8.1 is not acid so... you said so ..., so I am not mad, it just that big news agencies are creating clickbaits .... ;(

Apologies, but I don't really understand the parent post's concern or your confusion - do people really think that "too acidic" is a misleading description of the problem, and that this article is therefore clickbait created by "big news agencies"? If an animal adapts to N ph, and has problems at N-0.1 ph, then surely it's rational and honest to say that the animal's environment has become "too acidic" for it, regardless of how acidic the number "seems" to us? Is this somehow different from temperature changes, where I feel like most people wouldn't be confused by what we would feel is "cold" being described as "too warm" for another species?

"So acidic" is somewhat misleading when the ocean isn't "acidic" at all, at least based on conventional usage of the word as we typically refer to liquids with PH levels below 7 as acidic and above 7 as basic or alkaline. Also the use of the word 'dissolving' seems somewhat suspect as the crabs with shell defects simply didn't form their shells properly, it wasn't adult crabs melting away in an acidic slurry...

A less misleading title would be "PH changes in ocean affect crab shell formation" or something like that.

The ocean acidifying is perfectly fine terminology. You're looking at this through a politicized lens.

It is perfectly fine. It's also not what the headline says.

No offense, but is it possible your life experiences have you subconsciously looking for a political angle? I could be wrong, but the idea that "so acidic" is misleading because we're talking about values on the basic half of the ph meter is just way out there to me. Again, I can't see the difference between this and saying that 40 degree F water is "so warm" in some specific context, where in an information void that sounds cold. Similarly, acidity and alkalinity are purely relative in all my experience of the usage of those terms, both scientifically and colloquially.

Yeah, my life experiences are such that I've lived long enough to remember several times people thought the world was going to end, WW3 would happen, and a bunch of doomsday predictions that should have but haven't happened.

Or maybe it's the fact I'm Canadian and we generally push back against extremism, alarmism, most isms really.

I've heard there's a hole in the ozone and we're all going to die from cancer and I've heard that New York will be underwater and all the glaciers will be gone by 2020. I've lived through 2 US presidents everyone has said are Hitler and somehow, despite the uproar being the loudest today, the world hasn't come to an end and things actually don't seem that bad.

So yes, when I see headlines that are obviously click bait it hits this little part of my brain that feels compelled to say that maybe, just maybe things aren't all that bad.

> I've heard there's a hole in the ozone and we're all going to die from cancer

The reason you don't hear that anymore is not because there was no problem, but because the problem has been fixed by the implementation of the Montreal protocol. The ozon layer has been gradually recovering ever since.

https://en.wikipedia.org/wiki/Montreal_Protocol

Just because we avoided some disasters (WW3) and acted globally to prevent others (ozone hole) doesn't mean they weren't real issues with potentially disastrous consequences. In fact we should be looking at how we avoided some of those outcomes and learn from them. The ozone hole is particularly illustrative because of it's similarity to today's problem with CO2.

> Or maybe it's the fact I'm Canadian and we generally push back against extremism, alarmism, most isms really.

How about other forms of alarmism, the reducing use of fossil fuels will destroy our way of life, collapse the economy, etc? I see a lot of people worried about "climate alarmism" but they never seem to be concerned about there own alarmsism.

> and I've heard that New York will be underwater and all the glaciers will be gone by 2020

Citation please? I see this claim frequently yet either no citations are provided or they rely on the readers lack of comprehension, memory or both. The alarmisim is probably in your head.

As for calling it "too acidic", that's fairly obviously more understandable for the lay reader than "not basic enough" would be.

Here's some failed predictions:

https://www.rd.com/culture/predictions-that-didnt-come-true/

https://www.google.com/amp/s/amp.cnn.com/cnn/2020/01/08/us/g...

Any credible sources? In the first link, that's not a quote from Jim Hansen, that's a quote from Bob Reiss said that Hansen said 12 years earlier. I don't know how credible Reiss is supposed to be but there's no context to address Hansen there.

For number 2, yes they revised the timeline, the glaciers are still retreating. Does an extrapolation on a long running process even count as being alarmist?

"... so acidic..." implies the substance in question is actually an acid. That's what the title used.

"...too acidic..." doesn't carry that same implication. On some scale, something is more acidic than optimum.

At least, that's the way I interpret the comments above. After reading the article, I knew exactly what was happening and didn't really think the title was click-bait, but can see how others might perceive it that way.

I really don't understand why this distinction matters. If the ecosystem collapses because development is hindered, that's just as bad as the scenario where the animals were outright killed after developing just fine. It's a huge problem either way.

The headline is technically wrong, but the broad point, "things that we rely on are dying because of the changing pH of the ocean", is correct and meaningful.

Science doesn't operate on the theory that we can disregard the actual words and just go with the general flow, and when people report this way the inevitable corrections lend fuel to the "science doesn't work" fire. For the sake of getting people to take science seriously, let's try and leave that kind of "ignore the words and listen to the sound of my voice" to marketing.

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