I find it interesting that you did enough research to understand the flaw of the “half an eye” argument, but didn’t realize that perhaps that same flaw would apply to your “half a wing” argument. So, plus 5 points for realizing the problem with half an eye, minus 2 points for missing the wider application.

I agree that questioning things is very important, and there have been lots of questions in the history of evolutionary thought (Lamarckism being one example, a theory that was disproven by the work of a 19th century monk, Gregor Mendel). And there have been lots of small changes to the theory along the way, especially with the advent of genetics.

If you are interested in learning more, I have two resources for you.

First, I think that Dawkins’ “The Selfish Gene” (find some of it here ) is a great explanation of the topic.

Second, Understanding Evolution is a great website – I recommend starting with Evolution 101

Posted: May 28th 2009

See all questions answered by Eric_PK

Evolution is not unquestionable. Everyone questions it all the time, especially those who accept it. The important thing is that it answers those questions. That’s why it’s so useful. It tells us things we need to know.

You just need to think in intermediates, and tiny improvements. The beehive would have started off as a simpler, messier nest, more like those of wasps. The hexagonal chambers would have gradually developed from simple circular holes because the closer they got to that shape, the less space was wasted and the less material was needed.

Look at it geometrically. You can’t tessellate circles, but you can tessellate hexagons perfectly. Furthermore, the closest you can get to tessellating circles is to arrange them in a hexagonal pattern. It was a natural progression.

You accept that half an eye is useful, but you haven’t considered wings in this light. Birds couldn’t achieve flight with half-wings, or just slightly flattened arms, but they could fall farther without hurting themselves. At every stubby half-stage of the wing, it increased the bird’s safe falling distance if it extended just half a millimetre.

Eventually the length and surface area of wings reached the point where birds could safely glide any distance by making their terminal velocity a safe falling speed. After that, any addition of aerodynamic features or dexterity allowed them to control their descent and avoid hazards on the ground. Finally, they used muscle power to gain height, and flight was a reality. The bones got lighter, and flight got easier. Voila.

You chuck in a bunch of animals and claim evolution can’t explain them. Have you actually looked for existing explanations? Wikipedia’s always a good start, just search for any animal.

Of course evolution isn’t as obvious as gravity, because evolution only happens to living things and gravity acts upon all matter in the universe. The evidence for evolution is still plentiful and more varied than you might think.

I bet you’re not a fan of Richard Dawkins, but his 1991 lecture series Growing Up in the Universe is about the best evolution primer you can watch free online. This was long before he wrote The God Delusion, so his atheism stays in the background. If you’re curious, I think you’ll like it.

Regarding your request, the site’s creator wants to keep the focus on the writings of the resident atheists. The new thumbs up/down system is as much of a reply as you’ll be able to give.

If you’re interested in a full back-and-forth, I also write and moderate for Ask the Atheist (no relation) which allows comments. Check that out too.

Posted: May 27th 2009

See all questions answered by SmartLX

Scientists ask questions about the workings of evolution all the time. However, admitting there is much more to learn about how evolution works is not the same thing as claiming there are flaws or errors in the theory.

Those who criticize evolutionary theory for its deficiencies often lift quotes from Darwin’s Origin of Species to buttress their cases. The problem with this approach is that we have learned a great deal since Darwin published his book 150 years ago. Today it is fair to say, as Theodosius Dobzhansky did several decades ago, that nothing in biology makes sense except in the light of evolution.

If you are genuinely interested in finding out why science places such credence in evolution, try reading Why Evolution is True by Jerry A. Coyne or The Ancestor’s Tale by Richard Dawkins.

Among other things, I think you will find there the reason why, to paraphrase an old saw, half a wing may be better than none. You see most of the issues you raise have already been dealt with. The half a wing argument has no more validity than the“half an eye” argument you refer to later.

FYI, there are prominent biologists who are Christian and also think evolution is the best explanation of life on this planet. Frances Collins, who was prominent in the Human Genome Project until recently, is one. Kenneth Miller, the author of Finding Darwin’s God, is another.

The theory of evolution is supported by virtually all the available evidence from every scientific discipline that is remotely connected to it. The ideas of natural selection and common descent, which were Darwin’s chief contributions to our modern understanding, have been demonstrated in the field and in laboratories around the world. There is simply no scientific controversy about the validity of evolutionary theory generally. There certainly are controversies about some of the specifics. Hopefully, there always will be because it is in resolving such issues that we gain knowledge.

That’s not to say evolution is unassailable as a theory, but it is to say that it is today probably the most robust and best documented of the major theories at the core of all modern science.

Posted: May 27th 2009

See all questions answered by George Ricker

If I knew of some flaws in evolution theory I would be happy to acknowledge them.

Most often when people talk of flaws in the theory, they’re referring to things that the theory of evolution doesn’t attempt to explain, and is not supposed to explain. The theory of evolution accounts for the diversity of life on earth, and does so brilliantly. It does not stand or fall depending on our ability to comprehensively map the evolutionary history of life.

The living world is vast, and contains many mysteries. We may never know for sure exactly how certain forms or behaviors evolved. But lingering questions of this kind do not present a challenge to the theory of evolution itself. For one of these mysteries to present a real problem, or a 'flaw’, it would need to be shown that the particular form or behaviour in question could not have evolved under the core assumptions of modern biology. That’s different from simply pointing out that we don’t currently know how something evolved, and it’s a very hard thing to do.

This is what Intelligent Design advocates have tried to show, based on the ideas of Michael Behe. Behe claims that there are biological systems that are too complex to have evolved; that if you were to 'reduce’ these forms to a simpler versions of themselves, that they wouldn’t work. Behe calls these systems examples of Irreducible Complexity. One system claimed to be irreducibly complex was the bacterial flagellum. In Behe’s words:

“[An Irreducibly Complex system is] composed of several well-matched, interacting parts that contribute to the basic function, wherein the removal of any one of the parts causes the system to effectively cease functioning”

Irreducible Complexity, if it existed, would contradict evolution theory which demands each iteration of a form to work, to be useful somehow. Natural selection is short-sighted, it will not go down a route which harms the ability of a system to replicate in the short term, for a payoff millions of years later.

The idea of Irreducible Complexity makes a positive claim about the impossibility of certain systems to emerge through natural selection. But the responses from the scientific community have shown why this claim is false.

Here’s one way that IC fails; We might observe a system that does X, and notice that if we took away one of its parts, it could no longer do X. But IC ignores the fact that the system can still 'earn its keep’, evolutionarily, by doing Y instead. See the reducible complexity of the bacterial flagellum.

Another way IC is undermined is by an apparent failure to notice that natural selection can remove as well as add complexity to a system. Thinking about how a stone arch was built can be baffling if we assume that it must have been built by only adding elements one at a time. But if we realise that the building process can also include the removal of elements, then it’s easy to see how a stone arch can be built gradually, using a scaffold; we don’t need to suggest that a supernatural force must have put it together 'all at once’.

Bird Wings

We don’t know for sure how bird wings evolved, but we do have models that are plausible and consistent with evolution theory. I’ll call them Top Down, and Bottom Up.

Top Down: The development of stubby, flightless wings would have helped climbing creatures glide down from trees over increasing distances. These creatures may have 'earned a living’ in a similar way that modern gliding animals do.

Bottom up: We notice that modern birds do what’s called wing-assisted incline running (WAIR), this is flapping of the wings to help run up a steep gradient. Flapping while running can even enable an animal to climb vertical surfaces by pressing the body towards the tree trunk. A wing needn’t be capable of flight in order to be useful for WAIR. Here’s a PDF that talks more about research into wing assisted running.

In order for the existence of bird wings to represent a 'flaw’ in evolution theory, it would need to be shown that their development could not have happened through natural selection. In fact we have at least two sets of examples of how partial wings, while not yet suitable for flight, can be useful to an animal.

Next time you hear the phrase 'What good is half a wing?’ think of a flightless flapper escaping the snap of a predator’s jaws by running straight up a tree trunk.

Posted: May 27th 2009

See all questions answered by bitbutter