Human Eyes Are Wired Backwards
theconversation.com
theconversation.com
Also, the author's ignorance of biology concerns me. In one comment, he thought that color-blind people saw in grayscale. If you know how human cone and rod cells are set up, such an idea seems preposterous.
Well, there's some randomness in there too. I'm sure genetic local maxima get busted sometimes.
1. To move you to a "bigger hill". Imagine going from no eyes to skin spots that are slightly more delicate than regular skin, but are precursors of light-sensing skin cells^1. Over the course of generations, eyes can evolve.
2. To not be too deleterious. One spot of more sensitive skin won't cause the mutation to be immediately evolved away from; it's just not that bad for the individual.
When you say it's "practically impossible to improve through random effects", what is "practically impossible"? How have you weighed that against the number of individuals in a population, the number of random mutations each offspring has, and the length of time we're talking about? The question isn't "what are the chances a blind fish today has a baby with eyes tomorrow?" This question both understates the number of trials evolution has to generate something, and pins the target of evolution. Instead, we should ask "over millions of years, what are the chances that a given population evolves something useful?"
[1] I'm not claiming this is exactly how eyes evolved.
For the first issue, there are is a simple way of seeing what I'm talking about; If you are trying to optimize an algorithm for given results, there are three broad techniques which I will categorize for simplicity as 'stupid', 'random', and 'smart.'
For instance, if I wanted to sort a deck of cards, I could just shuffle it until I had a sorted deck. That's 'random.' This is not the worst you can do, and only if you do worse can random be an improvement. To do worse, you have to actively prevent the deck from becoming sorted. (For example, by using an algorithm that guarantees a 1-3-2 order at the start.) Randomness is not optimization, and stupidity is optimization away from the goal. Smart is convergence on a goal.
However, evolution is not a goal directed process. Those who exist are simply those who lived long enough in the environments they happened find themselves. Randomness doesn't improve any organism or any feature of any organism: it only improves diversity, which allows for more niches to be filled. I mean, maybe this increases the availability of food or the amount of space per organism or something, but it doesn't actually improve organisms. It improves the environment by making it less hostile to life in the abstract.
So it has nothing to do with hill climbing or optimization per se.
> ...it is practically impossible to improve through random effects.
It's true that evolution is not aimed at a specific target. I made that point in my comment.
>Randomness doesn't improve any organism or any feature of any organism: it only improves diversity...
Here is a list of examples of beneficial mutations: http://www.gate.net/~rwms/EvoMutations.html It includes things like "adaption to high and low temperatures" and "12% (3 out of 26) random mutations in a strain of bacteria improved fitness in a particular environment."
The claim is that random mutations can occur -- at some rate, low though it may be -- and are more likely to be kept through natural selection.
Intrepid cells (no doubt sick of the crowding in their native tumor) will sometimes set out to explore and colonize the unruly wild parts of the body. It will be hard, but a few of those colonists will succeed in establishing far-flung outposts.
Surely there will be a few environmentalist cancer cells that oppose the "development" of the body, but the common perception among cancer cells will likely be that those cells are just standing in the way of progress, and anyway that the body is so vast that a single cancer cell can't do very much to effect the outcome.
/remove tongue from cheek ;)
The best argument for evolution isn't a listing of how badly-designed we are, it's a simple observation that the one simple principle of natural selection through modified descent suffices to explain us. We don't need any other hypothesis. Therefore, the principle of parsimony kicks in and other, more complicated, hypotheses are ruled out. Not absolutely, but fairly strongly, at least until we find things that our current hypothesis cannot explain, which hasn't happened yet.
Besides that, there are many people who disagree that it suffices to explain us.
Of course, Occam's razor should be treated as a guide... it's no proof.
It's also useful because the complexity of the eye is often used as an argument for ID on the assumption that an incomplete eye would be useless, but for the eye we do have a long range of intermediate stages that would provide useful levels of sight, and we can show a long range of variations over eyes in existing organisms.
(see The Blind Watchmaker, "This means that the light, instead of being granted an unrestricted passage to the photocells, has to pass through a forest of connecting wires, presumably suffering at least some attenuation and distortion (actually probably not much but, still, it is the principle of the thing that would offend any tidy-minded engineer)".
In short, Dawkins argument is weak- it appeals to design tidiness, not to any real facts or logic about how evolution works. But as this modelling (oh, and I see they did some experimental work as well) shows, it's just as likely that the mammalian eye configuration isn't as bad as he said.
The arguments against intelligent design should be based on reality. Dawkins is probably right about this sort of thing (that there is no ID), but he's typically right for the wrong reason (specious logic).
(Dawkins then further argues against parallel evolution, although we're now finding out it's also quite common. he's wrong about a lot of things).
I should further argue that finding the eye in this configuration "backwards" according to some, is really just applying human aesthetics about how things should be engineered, where biology is a combination of happenstance and optimization. I suspect, as we tease out the biophysics of the eye further, we will find many more examples of how Dawkins' simple logic (which isn't really logic, but more based on aesthetics and intuition) doesn't really explain things.
What qualifies as "messed up?" Having a design that appears suboptimal?
What would be not-messed-up, or what would be perfect? Having vision equivalent to a hawk? A telescope?
Why do you assume a creator being would necessarily choose to make perfect things? What if creating perfect things was not the creator's purpose? What if its creation was perfect for its intended purpose?
If a supernatural being exists and created the universe and us, it's ludicrous to think that we could put ourselves in its place and say, "Well, obviously he should have done it like this instead, therefore he doesn't exist."
We can't even understand how our own brain works, but some of us think that we are smarter than God. Regardless of what you believe about the existence of a supernatural creator, it's obvious that we would be inferior to such a being.
If you refuse us the right to make any claims about a god, you also refuse the right to make any arguments for it.
Obviously, ars was talking about the gods mentioned in popular religious texts. These texts make very specific claims about what their gods are and do.
Arguing about arbitrary gods is, of course, largely fruitless. However, belief in them is equally fruitless.
From another article on the same site, https://theconversation.com/a-dark-night-is-good-for-your-he...
"Light from the Sun is strong in blue, short wavelength light ..when it comes in the evening or during the night, it fools the body into thinking it’s daytime. We now know that this bright blue light has the strongest effect on lowering melatonin during the night. Your tablet, phone, computer or compact fluorescent lamp (CFL) all emit this kind of blue light."
http://www.smithsonianmag.com/science-nature/the-top-ten-dai...
Humans are optimized in some very specific ways, but at the expense of some serious downsides.
As a related aside, I think its this misunderstanding that confuses people into preferring creationism. If one holds the anthropocentric view that humans are the peak of biological evolution (itself a meaningless concept... Evolution is about fitness, it's not directional), believing in creationism is a lot more understandable.
> One of the reasons it is so difficult to stop hiccupping is that the entire process is controlled by a part of our brain that evolved long before consciousness, and so try as you might, you cannot think hiccups away.
I can. Reliably. I concentrate in the general direction of my diaphragm, and often times I can stop the third hiccup before it happens. I have to wait until the second hiccup before I know I'll have to use the technique. The only time I can't do it is when I've been drinking, which is, coincidentally, when I get them the most. I can't concentrate the way I need to, it's like that part of my brain is shut off.
That would be a much more compelling anecdote about control.
A couple of times I've gotten home realization dawns that I'm still hiccuping. Two, three hiccups later, they're gone. There's something about being alone in my room that makes me more capable of doing the technique than when I'm at the bar.
Yes; “This project is doomed.”:
http://threepanelsoul.com/2010/07/05/on-design-by-committee/
And so is every other species. We've all been evolving together on this planet for the same amount of time.
This is why driving species to extinction is so spectacularly stupid — it squanders our collective legacy of genetic information, hard-won over billions of years of struggle. How many discoveries like this will never be made because we destroyed the species? Worse, how many useful functional species are we depriving ourselves of (including functions we don't even know we need yet)?