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Comment by inkaudio | Hacker News Reader

I love science & technology therefore I'm alarmed because so many scientist and technologist don't see the inherit paradox in evolution. Natural selection makes it virtually impossible for animals to adapt via the proposed mutations. Natural selection happens immediately, valuable life preserving mutations are suppose occur (typically) over thousands of years.

To illustrate Arctic terns are dying because they are not able to adapt to climate change. Arctic terns eat herrings a cold water fish, as the water gets warmer, these fish seek colder waters, possible by going deeper in the waters. According to biologist other birds in the Arctic can dive deeper to grab the cold water fish Arctic terns cannot, so they and their chicks starve to death. This is natural selection, there is no time to adapt via mutations, adaptations must happening quickly.

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What's to say that species will adapt all the time? It could be that terns won't be able to adapt fast enough, and will die. There's die-offs of individual species all the time, and historically there's been several major multi-species die-offs when conditions have changed too rapidly.

Mutations don't have to occur at the point of their necessity. Mutations that survive can be survivorship-neutral (or nearly so), but suddenly become useful many years later during condition changes, and thus become dominant.

Take eye colour. As far as I'm aware, aside from random sexual preference, there's no real survivorship benefit to have a particular colour eyes. So we have populations with various different colour eyes. If aliens who hate people who don't have blue eyes show up and kill everyone without blue eyes, that mutation suddenly becomes selective.

The mutations that help species survive changes in conditions are usually already there when the change shows up.

Don't underestimate natural selection. Animals need essential traits to survive at birth. Now consider that most animals are specialized to their environment, how did they get to that point ? What did an Eagle do before it eyes became specialized for air to ground hunting ? How did it survive before it can fly ? How did these animals survive is these environment during their evolution ? That's the paradox, natural selection works too well for evolution by gradual mutation to work.

You're can't rewind an animal x million years and place it in the same environment. You have to rewind the rest of the ecosystem as well. One possibility, for example, is that when eagle's eyes were less specialised for air to ground hunting, rodents were less specialised to hide themselves from airborne predators - because they hadn't had selection pressures from such specialised birds of prey.

Congratulations, you are front row center to a mass extinction event. There was not time for the dinosaurs to react to the meteor either.

The theory that dinosaurs died due to a meteor is already outdated.

Is it? Are you being pedantic about the term "meteor" or is consensus behind something other than a collision? Asking honestly and aware that Wikipedia isn't always going to be correct. From Wikipedia:

"It is generally believed that the K-Pg extinction was triggered by a massive comet/asteroid impact and its catastrophic effects on the global environment, including a lingering impact winter..."

Same page then suggests volcanic activity, etc is a less popular theory.

You probably won't read this, but:

http://www.slate.com/articles/health_and_science/animal_fore...

It's not enough that an asteroid hit the Earth, but it's such a simple theory that everyone can remember, it has been popularized by everyone.

I thought it was a given (for anyone keen to read more than a headline) that the impact implied a long period of changes and involved more than just the strike itself?

I did assume however that volcanic activity could've been as a result of the impact.

Don't underestimate natural selection, specialization is more common than not. Most animals are so specialized to their environment it would be impossible for them to survive without these inborn essential traits. We can't demonstrate how they could survive while evolving these essential traits.

The terns able to dive deeper (for whatever physical reason) survive and breed.

Exactly, survival for most animals are always based on their immediate ability to adapt, not the ability to adapt over thousands of years, that is the paradox of evolution. Animals supposedly evolved to have these specialized features essential for survival over thousands of years, but natural selection is in conflict. Animals need to survive their conditions immediately, they can't wait for their bodies to evolve.

> Exactly, survival for most animals are always based on their immediate ability to adapt, not the ability to adapt over thousands of years

Incorrect - it's both. Obviously adaptivity to rapid changes is key, but species don't only disappear/change due to extinction-level immediate events. Individuals also get edged out by their peers (or members of other species) who manage to outcompete them just that little bit for food, or sexual attractiveness, or any of many other reasons.

I don't think you understand how it works. It's not about animals adapting to survive, but the survival of those best equipped. Not everything survives.

Imagine there's a life and death surprise test on evolution. Demonstrate knowledge and you live. Fail to do so and you die. Part of the population already has a reasonable understanding of it. Others don't. You're looking at it from the perspective of the less knowledgeable cramming their study to pass the test. Evolution in this contrived case can select for those who already happen to understand the topic.

Yes, those best equipped ! But how do you get it equipped ? That's the issue. Yes, not everything survives. But those that survive have all the specialized equipment needed to survive because ?

This is just a very tedious rehash of the very old, already answered, "Eyes need to be perfect to work. So how did eyes evolve?"

Natural selection does not occur in a series of instant events! Evolution happens over a long period as the result of a statistical advantage in survival rate. It does not work for rapid change in environment. I don't think anyone is claiming that.

Natural selection isn't something that's applied to individual animals, it's something that exerts pressure on whole populations over many generations.

To go with your Arctic tern example, just because one bird can dive deeper doesn't guarantee it's survival. It might still get eaten by a predator or catch a disease or just have a run of bad luck that causes it to starve. However, the birds that can't dive as deeply run the same risks (assuming there's no additional risk to diving deeply) and, over a long time and with a large population of birds, those that can dive deeper will survive to breed more often, until eventually the whole population carries that trait.

You've got it wrong. There is always variation in a population. If a new environmental pressure arrives, some of these variations end up being more successful than others. In some time you might not find any terns who can't dive deeply anymore. There is also a lesson in that that variation is important (for example also in economics, agriculture and so on) - don't bet your countries economic future on just one industry, for example. Evolution theory applies everywhere.

I did not say there is no variation in population. Animals that survive have the ability to survive before environmental pressures. Why ? Yes there are variations among animals, and those that have the trait for survival, survive. The argument is how do these variations that survive get these important trait ? Especially when these traits are specialized to the environment. How do they evolve these specialized traits in time ?

You are only asking for the basics of evolution, every textbook should have you covered (or even Google). And it doesn't happen the way you imagine it, those traits don't have to evolve from one day to the next. Bears can live in Canada because they can hibernate, they didn't live there and had to learn how to hibernate on short notice when winter came.

Have you not read textbook that explained specialized traits as reaction to the environment ? How could that be possible when these traits are needed immediately. You miss the point, why don't we have thousands of animals with the ability to hibernate that don't need them ? Of course traits don't have to evolve rapidly if you already have them or don't need them. But why would you already have the ability to hibernate efficiently if you don't need it ? Why would a bird of prey evolve the ability to hunt from the skies at relative high speed before it can fly ? I'm sorry I read the books there are no legitimate answers. Like said I love science and technology.

> You miss the point, why don't we have thousands of animals with the ability to hibernate that don't need them

Because a tendency to hibernate is likely negative for survivorship when it's not necessary - if lots of other animals are moving around and you aren't, then something is more likely to come and kill you.

On the other hand, lots of animals have other varying traits that aren't obviously useful, but don't exact a significant enough toll to cause them to disappear.

> But why would you already have the ability to hibernate efficiently if you don't need it

Doesn't that assume that bears were transported into Canada and survived because they could hibernate? Isn't it perfectly possible that they moved further north gradually, increasing their tendency to sleep in cold conditions as they did so?

In case of hibernation it seems very plausible that an animal evolved to sleep longer and longer, to preserve energy. I don't understand your problem? It could also work this way: an environment had enough food to sustain 20 bears in winter. If they sleep longer, the environment can sustain 40 bears. If they sleep even more, 100 bears can survive. The population would then grow from year to year, while sleeping more and more. What books on evolution have you read?

Also (obviously) if they are not able to, they all die.

Species go extinct all the time and the original statement about "hey this one species isn't evolving in front of my eyes so evolution isn't a thing" is an old argument about evolution that has been disproved a million times.

Nowhere in evolution theory does it say that it has to take 1000s of years. Neither does it claim that every species would find a way to adapt to any change of environment.

You are just creating strawmen to support your belief. Evolution theory is not even confined to biology. You can watch it life in computer simulations if you want to.

Of course not every species would find a way to adapt. The issue is species have to be equipped to survive. How they get there ? Survival isn't passive but active. How do you survive a change in season with no time to adapt. For example animals that can hibernate must have that ability before it is required. But why would it evolved that ability in the first place ? Why is it that the animals that can hibernate are the ones that can't survive without it ?

No strawman here, how long did it take for birds to evolve ability to fly ? A few days ?

You are thinking about it backwards. Of course first there were only animals who couldn't hibernate, and who couldn't fly (for example single cell life forms...). It's not as if god dropped some bears into Canada and then when winter came they suddenly had to evolve the ability to hibernate.

Why don't you go grab a book about evolution theory that explains all those things?

I don't know how long it took to evolve flight, but it doesn't really matter. I could guess: flying underwater is a lot easier than in air, because you can drift even if your wings (fins) don't really help you control your direction much.

The first animals that could fly above land probably couldn't fly like today's birds either. Perhaps they could only drift a little while jumping from a tree. Or perhaps they were tiny animals that could actually float in the air (on a smaller scale it works), so that forming half working wings was some advantage already. The reality is probably something else, as I said, I don't really know.

You could pose billions of questions of that kind about evolution (why did animals evolve to do this and that, and how). Just because a random evolutionist can't answer every such question doesn't mean it is wrong. It just means you have to look up the answer yourself, or research it yourself. Biology is not a finished field of research.

The reason I ask about the how long flight took to evolve was because it was argued that evolution does not take thousands of years, and that's not true.

I've read the books that's why I see the paradox. I'm not playing games, if there are factual answers I would not be asking questions here. If an animal could survive for thousands of years without hibernating there would be no reason for it. It could even prove disastrous making the animal easy prey.

Moreover the dynamics of traveling underwater and flying in air are different. Features that are great for flight are not so great for traversing underwater for an extended period of time. There are animals that can glide today, but even there ability to glide has to evolve, and during that evolutionary process an evolving glider is a disadvantage. It is not neutral, it slows the animal down. If you are going to debate with conviction your answer should not be "I don't really know".

Yes, biology is far finished so let's not pretend like it is.

There are lots of animals that don't hibernate. Have you considered that you misynderstoid evolution theory? Biology isn't complete doesn't mean the parts known so far are wrong.

Can't write longer replies now because I only have a phone atm.

There is a smooth and quite obvious progression from sleeping to hibernation: simply extend the sleep period during certain times of year. If the environment is such that this will be beneficial, it'll be selected for over the long term. Certainly, in an environment where hibernation is absolutely required, it's not going to evolve - but the world is a diverse place with a lot of intermediates, and something that's necessary on the other side of that ridge might help here while I can nonetheless survive with a lesser version.

Your example proves the exact opposite of what you think; natural selection works as we suspect. The environment changed, the creatures best suited for the new environment will survive.

That is what I said. That is my point.

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