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“It suddenly struck me that that tiny pea, pretty and blue, was the Earth. I put up my thumb and shut one eye, and my thumb blotted out the planet Earth. I didn't feel like a giant. I felt very, very small.” – Neil Armstrong (1930-2012)

Fresh Reads from the Science 'o sphere!

Monday, February 02, 2009

Give Us A Hand

Some of my readers may be aware that the bicentennial of Charles Darwin's birth is coming soon, on the 12th of February. This year is also the 150th anniversary of the first publication of On the Origin of Species.

2009 has been marked by the International Union of Biological Sciences (IUBS) as Darwin Year, and there are many celebrations and activities planned all over the world.

Biochemistry professor and prominent science blogger Larry Moran considers Darwin to be the greatest scientist who ever lived.

This is arguably true but that view will always be debated by supporters of other great scientists like Isaac Newton or Albert Einstein.

Personally, I have to admit that he is not my favourite scientist (Santiago Ramón y Cajal and Motoo Kimura come to mind) but I cannot dispute the immense impact of Darwin's discovery of natural selection.

Together with Alfred Russel Wallace, Darwin laid the early groundwork for evolutionary biology, which after years of correction and refinement by many other scientists, has gradually become the unifying concept in biology today.

This is a big change, not only within the confines of academia, but also in the wider society. With the understanding of common descent and incremental change, people now have access to greater insights into the detailed workings of Nature than ever before.

Take for example this salient question: "Why won't God heal amputees?"

That could have been a deep mystery two hundred years ago, since limb regeneration has never been observed in human beings but are possible in many other animals.

Salamanders can regenerate whole limbs, tails, parts of their hearts and even parts of their eyes.

Fish can regenerate much of their central nervous system, including the spinal cord.

And planarian worms can regenerate pretty much any part of their body - even their heads!

From a theistic perspective, especially for people who believe in an omnibenevolent God or Gods, this is very hard to explain.

Why would the Gods confer the "lowly" worms or fish such an amazing ability to recover from severe injuries, but yet not provide the same ability to human beings - who ought to be the centrepiece of creation?

The relative level of impairment is mindboggling; human beings cannot even regrow a finger, let alone an arm or a leg.

So many people had to endure a lifetime of pain, suffering and paralysis from lost limbs or broken backs. Ironically, many of them were soldiers who had fought so hard and so faithfully in the name of their Gods.

The odd thing is that people do have extensive regeneration capability in the liver, so it's not as if the Gods could not create this ability in human beings - certainly it wouldn't be a problem if they really were omnipotent.

So is this compelling evidence that the Gods are cruel and capricious?

Or maybe the Gods are giant transdimensional Worms, Fish or Salamanders? That would explain their bizarre love affair with these animals.

Since there were no other explanations available, in the past people could only hope and pray that someday their small request would be granted by the Gods and their limbs would grow back.

But that never happens. Perhaps the Gods work in mysterious ways.

With the advent of evolutionary biology however, the answer becomes crystal clear:

Human beings don't stand isolated as the centrepiece of special creation; they evolved from another species of animal in the past. Closely related species tend to share more common features than more distantly related species.

Our closest living relatives are the other great apes. Since none of them can regenerate limbs, it isn't surprising that humans also cannot do it.

In fact, no mammal can regrow a limb. That ability has been lost ever since our ancestors diverged from the ancestors of modern salamanders over 350 million years ago.

Thus you now have a systematic explanation that does not require the postulation of any good, evil or bizarre Gods, and saves you the stress and confusion of needing to know what they want. There is no need to beseech the Heavens for a cure either.

The only real solution is to build the replacement limbs ourselves, by learning more about regeneration from the animals that can do it, or by inventing robot limbs that mimick the function of biological limbs.











When you realize that no amount of hoping, praying or word twisting can regrow a missing limb; you will see why one can only understand Nature by scientific investigation, and why physical problems can only be resolved by physical solutions. The awareness of the irrelevance of supernatural "solutions" helps to spur efforts towards scientific discovery and technological innovation.

This, to me, is a vital implication of Darwin's legacy.


Would you like to know more?

- Review article: Why is limb regeneration possible in amphibians but not in reptiles, birds, and mammals? (Galis et al. 2003, Evolution and Development)


- Time Tree (a public knowledge-base that uses a hierarchical system to identify all published molecular time estimates bearing on the divergence of two taxa)

20 Comments:

Anonymous said...

Asking why bad things happen is really another instance of putting the cart before the horse. So what if humans cannot grow limbs like some creatures do? Don't forget that our ribs is the only part that can grow itself back too. The human body has its own recuperative prowess. Question is, who put it there in the first place? Even if you allege bad design, it does not negate the fact of design or that there is a designer. So yes, bad things happen. But wait, why call it "bad" as if it is a moral issue? To ask it in a moral framework implies a moral standard which also means a moral lawgiver. If there is no Creator God, then any notion of good and evil does not exist. So it's time to put away the smokescreens and deal with the issue of origins. I can assure you that there are answers to the so-called theodicy issue, but short of acknowledging that there is a God to begin with, no answers will be forthcoming, just brute reality to live with in a purposeless and meaningless existence, just like what Dawkins said.

Anonymous said...

Think about it. If it requires human intelligence to build an artificial limb which hardly can do everything a human limb can do, and is hardly as complicated and complex as a real human limb, then what can we conclude of a real human limb other than that it must have been designed by a higher intelligence?

The Key Question said...

"So what if humans cannot grow limbs like some creatures do?"

How can you say "so what"?

Once again you dismiss the main point of my article in order to change the topic to something else. The ability to regenerate limbs, spinal cords and heads would alleviate a lot of suffering in humanity, but it is only possible in a variety of "lower" animals.

I already gave you a clear explanation why this is the case from an evolutionary perspective.

Unless you believe that God is a giant Salamander you must account for why she would deny basic limb regeneration to her most favoured creation.

Not even a finger? Come on, surely the Creator of the Universe couldn't be that stingy!

"If it requires human intelligence to build an artificial limb which hardly can do everything a human limb can do, and is hardly as complicated and complex as a real human limb, then what can we conclude of a real human limb other than that it must have been designed by a higher intelligence?"

I hope that you are not trying to claim that the Luke Arm was supernaturally and instantaneously created - Dean Kamen's team went through numerous versions before they came up with that one (see the video in the link), and it isn't even ready for production yet.

As for the appearance of design, that serves to emphasize the achievement of Darwin and Wallace - through descent with modification, Nature can preserve adaptive features and prune away deleterious features (but not perfectly) in gradual steps which are not only evident from the fossil record, but also visible from population genetics and molecular genetics.

The "higher intelligence" that you speak of need not be a supernatural trait, but is simply the emergent trait of Nature - a system comprising living organisms as well as the non-living environment.

You might have heard the Gestalt expression that "the whole is greater than the sum of its parts." Nature's ability to "design" living systems via random mutation and natural selection is greater than the sum of all the interactions of individual organisms struggling to survive.

You can personify Nature as a "God" if you wish but note that "he" was also the product of evolutionary processes, is indifferent to the life of any particular individual, and doesn't grant special requests through prayer or ritual.

Of course I will be instantly disproved the moment you can demonstrate that your prayer or ritual can regrow a severed finger.

Anonymous said...

Again you are missing the point. My "so what" reponse is to get you to look at the deeper issue. Where does the designed hand come from in the first place is a more fundamental question than asking why it cannot regrow itself. Whether something can regrow itself or not does not deny the fact of design or the existence of a designer. It is ludicrous to compare humans with another creature and ask why humans do not have a particular feature of that animal. Things are designed to function the way they are designed to. You want to turn your head like an owl does? You want to have eagle eyes? You want to be able to lay eggs? You want to breathe through gills? How about all the above, and why not? I don't think you even know what you are asking for, as all you want to do is to poke holes at the notion of a Creator. If you can do better than Him, then let us see you make something out of NOTHING. Make a better human if you can. Turn a non-living thing into a living thing if you can. Then you may not be so smug after all and the smirk on the face may go away in humility.

To talk about apparent design is to really engage in denial. Humans are well capable of recognising design and design features when we see them. And Dawkins is living in one great delusion himself and getting others deluded by asking them to deny what they see and attribute to some kind of optical illusion. The fact is that NO ONE has ever seen incremental changes take turns one kind of creature into another over millions of years. Why is why Dawkins said "Evolution has been observed. It's just that it has not been observed while it's happening".

But back to the issue of origins, and I am sticking to that while you go off tangent and talk about the effectiveness of prayers and rituals and what not. I credit the existence of the universe to a Creator. You credit it to Nature, which is simply to deny the Creator. It's a suppression of what you know to be true. You have to keep borrowing terms of design (e.g. systems) to talk about nature and yet at the same time deny the fact of design. Looks like you are not living consistently with yourself.

BTW, how do you know that God is also part of the evolutionary process? Aren't you already ASSUMING evolution to be true when you are supposed to show that it is true? I do not deify nature into God, for to do so would also mean that I am God, or a part of Him, which would be more like pantheism. In any case, to argue that God is also part of the evolutionary process of nature still leaves the question of origins unanswered. In the Christian worldview God is OUTSIDE of nature, in fact He is the CREATOR of all that exists in our universe which had a beginning. Your worldview leaves it to chance random processes and would rather that it be a question mark than to think that it is God. That again is to be in denial and suppression of knowledge.

If someone does report a severed finger regrowing itself after prayer would you really believe? I don't think so. Rather you will cook up excuses after excuses to deny that such a thing ever happened. You will then demand controlled environment where a finger is chopped off, prayers uttered, cameras rolling etc. That's what unbelieving hearts do. It will be in fact testing God according to YOUR own worldview when the Christian worldview never at all entertain the notion that God jas promised to regrow our body parts by prayer. In fact, when Jesus rose from the dead, you still have people not believing that it happened and the religious leaders even bribed the soldiers to lie about the missing body. My point is that the evidence is not really the issue here, but the will is.

I apologise for the longer reply, but would really hope that you can see what I am getting at, about not putting the cart before the horse.

Anonymous said...

Consider also Discover magazine's article here http://discovermagazine.com/2008/dec/10-sciences-alternative-to-an-intelligent-creator

It is clear that the writer does not want to recognise that there is a Creator. He would rather posit a multiverse scenario (speculative) which even noted ex-atheist Anthony Flew finds fault with. But that's what the Bible says man will do, that man will deny the Creator when the reality is that creation is pointing to God, which is why the Bible also says that man is "without excuse".

Anonymous said...

Consider also Discover magazine's article here http://discovermagazine.com/2008/dec/10-sciences-alternative-to-an-intelligent-creator

It is clear that the writer does not want to recognise that there is a Creator. He would rather posit a multiverse scenario (speculative) which even noted ex-atheist Anthony Flew finds fault with. But that's what the Bible says man will do, that man will deny the Creator when the reality is that creation is pointing to God, which is why the Bible also says that man is "without excuse".

angry doc said...

"I credit the existence of the universe to a Creator."

And I credit the existence of a universe to a Designer AND a seperate Creator.

After all, who said the Designer had to be the same person as the Creator?

Isn't it also possible that the universe was designed by an Intelligent Designer, the plans then given to a Creator, and when the whole project was completed the First Mover set everything into motion, after which it was given to the care of the Deity?

I am not sneering, anon, but merely pointing out that the fact that the universe may have a supernatural origin does not automatically make your version of the creation myth true - the Hindu worldview sees creation as a trimurti of a Creator, a Sustainer, and a Destroyer; in fact, the Hindus view the existence of the universe as cyclical instead of linear.

We can speculate on the nature of origin, but as you can see anyone can speculate on the nature of the origin and come up with a worldview and indeed a religion.

The Key Question said...

"But back to the issue of origins, and I am sticking to that while you go off tangent and talk about the effectiveness of prayers and rituals and what not. I credit the existence of the universe to a Creator. You credit it to Nature, which is simply to deny the Creator. It's a suppression of what you know to be true. You have to keep borrowing terms of design (e.g. systems) to talk about nature and yet at the same time deny the fact of design. Looks like you are not living consistently with yourself."

So you intend to deny Nature?

And this article is about the inability of human beings to regenerate limbs.

You know that you can claim anything if you don't have to support your views with evidence. You can even claim that I'm going off tangent on an article on the inability of human beings to regenerate limbs when I am specifically talking on the topic of the inability of human beings to regenerate limbs!

How incredible is that.

Anonymous said...

Wolf,

You suggested that the Creator need not be the Designer. But other than your own speculation what does this rest upon? As for me, I did not conjure my beliefs from thin air. I believe the Creator who made everything has communicated to us. He is not someone who wound up the clock and then left it there.

Again let's not put the cart before the horse or jump the gun or make hasty conclusions. If you truly believe that there is a Creator, then on that we stand on the same page. Then we can move on from here to deliberate on which creation account is likely to be true or whether all are false.

Anonymous said...

Who's denying nature? I'm simply not deifying it.

As to inability to regenerate a limb, you are again missing the point. Does the inability to do so negate the fact of design? Yes, a lizard may grow a limb or a tail, but that's because it is DESIGNED to do so, it has the genetic INFORMATION to do that. Humans don't, and it is also by design.

Wolf said...

"Humans don't, and it is also by design."

So does it mean that if you do try and regenerate a limb (say via stem cells, or whatever), you're going against the will of the creator?

The Key Question said...

"As to inability to regenerate a limb, you are again missing the point. Does the inability to do so negate the fact of design? Yes, a lizard may grow a limb or a tail, but that's because it is DESIGNED to do so, it has the genetic INFORMATION to do that. Humans don't, and it is also by design."

Thanks for returning to the topic at hand.

Now the question remains: Why would a Grand Designer confer limb regeneration to salamanders (they are amphibians, not reptiles), but not at all to any mammal, including human beings?

For other readers who are interested in the molecular explanation of this observation, please check out this good review article.

Why is limb regeneration possible in amphibians but not in reptiles, birds, and mammals?

http://biology.leidenuniv.nl/~galis/pdfs/pdf24.pdf

Anonymous said...

Wolf, if you can grow a limb that was chopped off, by all means! The Bible is silent on it. If you can really do that, it only proves that you need INTELLIGENT DESIGN to replace a limb, which actually supports my belief in special creation.

Anonymous said...

How come birds have wings to fly but humans do not? How come God did not confer us with turning owl heads? All these questions are really missing the whole point. God designed and created things in His own way. That's what we call "sovereignty". If you are God then you can do what you want and make the most queer human with all kinds of features. Since you are not God then asking such questions is meaningless.

But having said that, back to the issue, does not being able to grow limb, or to put it your way, God not allowing man to grow limbs, makes render God non-existence or disqualifies Him from being Creator of us?

Anonymous said...

How come birds have wings to fly but humans do not? How come God did not confer us with turning owl heads? All these questions are really missing the whole point. God designed and created things in His own way. That's what we call "sovereignty". If you are God then you can do what you want and make the most queer human with all kinds of features. Since you are not God then asking such questions is meaningless.

But having said that, back to the issue, does not being able to grow limb, or to put it your way, God not allowing man to grow limbs, makes render God non-existence or disqualifies Him from being Creator of us?

Anonymous said...

I apologise for the double postings. Tendency to click the mouse twice. Can you remove the redundant ones? Thanks!

Anonymous said...

I like this series of blog posts. Looking forward to the next installments :D

I for one, can't be bothered to "compare notes" with a "believer". Mindsets can't change from the outside anyway.

Anonymous said...

Judging from your posting, you don't seem willing to have your mindset changed anytime soon either, Amused.

Anonymous said...

Anon 11:51

I think should be "ready to have my mindset changed" around the time you're ready to have yours changed.

Anonymous said...

Amused,

I went from nonbeliever to believer, from theistic evolutionist to young earth creationist. My mindsets have changed. Have yours, will yours? Of course right now I am very convinced of my position and will defend it to the best of my limited ability. But I will never resort to suppressing your view nor deny you the right to question my beliefs, whther it is my blog or not.