Friday, February 17, 2006

Why we struggle to understand evolution

Despite the overwhelming evidence for macroevolution, part of my mind still battles to accept the fact that such large changes can occur in living organisms. Why is this so? Why do some, if not many, of us have a hard time accepting and understanding biological evolution?
 
Richard Dawkins, in the preface of his book The Blind Watchmaker, provides possible reasons. First, humans are successful creative designers. So much so that we are predisposed to the idea that complex elegance is an indication of purposeful design. Evolution is counter-intuitive in this sense. Second, our brains are built to deal with events on totally different timescales from those that characterise evolution. We can grasp timescales of days, months, years or decades, but battle to understand change that takes place over millions of years.
 
This last point is important when one is thinking about the differences between microevolution and macroevolution. Microevolution is easy to grasp because it takes place over a period of years and decades. However, our minds naturally stumble when it comes to macroevolution. How do we overcome this problem? The key to understand macroevolution is to realise that if you give microevolution enough time, it will result in macroevolutionary change. In other words, macroevolution is simply a whole lot of microevolution.
 
Take the human embryo, for example. Straight after conception, hundreds of cellular and genetic changes - all tiny changes - take place over a period of nine months to transform the little pack of cells into a human baby. But this is not all: thousands of changes occur to transform the baby into a child, then into a teenager, then into an adult - over a period of many years. If someone compared a photo of an embryo to an adult human, they might – hypothetically speaking - find it unbelievable that something so small can change into something so large and so different. A similar analogy can be drawn regarding an oak tree: how can such a small acorn develop into a massive, complex organism? Such macro-change does seem unbelievable, but it does happen, thanks to all the small micro-changes that take place over long periods of time. We can see this kind of thing happening in the natural world all around us.
 
Evolution is similar: it is difficult to imagine how birds evolved from reptiles, or how humans evolved from small mammalian-like creatures. Our brains battle to conceptualise large changes. But if we allow thousands upon thousands of natural micro-changes over millions of years, it doesn't seem that impossible at all.

16 comments:

Stardust said...

We should never stop questioning. Just because we don't understand things doesn't mean we should make things up to explain what we do not yet know.

Kevin said...

Greg wrote:
God still loves you. The devil is tricking you into believing that it's all about you. Put your armour back on.

Thank you for your comment, Greg. I appreciate your concern and I know where you are coming from, but I’m sorry to say that I’m not convinced by what you say. It is possible that some creature (such as the devil) is affecting my thoughts (in some mysterious way that I can’t detect) that is resulting in my un-belief in God and the Bible. But how can I know this for sure?

And another point: how do you know that you are not the one who is been tricked? Maybe the ultimate truth is Islam, and the devil is tricking you into believing the false religion of Christianity. Or the Mormons can claim that the devil is subtly playing tricks with your mind so that you don’t realise the ultimate truth of Joseph Smith’s teachings. My point is that the ‘devil (or any kind of malevolent, invisible creature) is tricking you’ hypothesis can be used by almost every religion or supernatural belief. In other words it proves nothing, and thus does not sway my position.

Thanks again for your comment.

Kevin

sdfa sdfasdfadsf said...

Ah, come on 'Greg' - you're posting on the blog of an ex-christian who knows what he's talking about. I find it rude and condescending to write off a well-written, thought-provoking article to "a trick from the devil." C'mon, if you wish to evangelise, try stating why you think what you do. We give reasons for our beliefs, don't assume we've accepted your premise and can empathize when you talk about the devil. We cannot as we don't believe it.

You need to learn how to evangelise - you're not going to 'win people for Christ' with such condescension and vehement bigotry.

Roger Saner said...

"In other words, macroevolution is simply a whole lot of microevolution.

In response to your analogy about the baby growing up into an adult and the acorn growing into an oak tree - the reason we're not suprised that there's such a difference between the first and last versions of the same thing is that we see all of the in-between stages (child, teenager, young adult - for instance).

My question is - assuming macroevolution as a reality, where are all those in-between stages?

Roger Saner said...

My second question springs from: But if we allow thousands upon thousands of natural micro-changes over millions of years, it doesn't seem that impossible at all.

Agreed - unless there's something introduced into the system which could not have been the result of incremental change. At that point this theory breaks down.

Anonymous said...

r0g3r,

You may want to look at the following website www.talkorigins.org/faqs/faq-misconceptions.html In fact, there are many transitional fossils. Evolution could not be considered a scientific theory without years of tests that supported the initial hypothesis. Science does not just make something a theory because it sounds good, it has to be supported over and over again.

Roger Saner said...

Thanks, Stephanie - taking a look now...

Roger Saner said...

The site you pointed me to has some answers to my first question (they phrase it as an answer to "There are no transitional fossils") but they don't address my last statment - that the theory of incremental change breaks down if we have something which could not have resulted from incremental change.

This is a correct logical statement, but it assumes that the theory of evolution is a theory of incremental change - and I don't know enought about it to say for sure. I brought this up with my Dad who's a geologist and (probably) hard-core (bad pun) evolutionist and he did say there's something that explains it but we never actually got around to what.

Anonymous said...

Do you have any examples of what would not involve incremental change?

Anonymous said...

Could it be that the main reason people fail to understand evolution is because they have been taught not to understand evolution? As a Christian, I was told by my non-scientist pastor that evolution was silly. As a child, I was told that god made me. So, I never tried to understand evolution....why did I need to?

Once I started questioning my beliefs, I started to educate myself on evolution. At first, it was hard to understand because my brain was still recovering from what had been drilled into my head my entire life. When someone is brainwashed, they cannot just snap out of it. It takes time to come to the understanding that everything you were told is untrue. Slowly, the past untruths embedded in my brain are disappearing and the clear evidence for evolution has made it much less confusing.

Kevin said...

Roger wrote:
but they don't address my last statement - that the theory of incremental change breaks down if we have something which could not have resulted from incremental change.

But doesn't the very existence of transitional fossils lend weight to the argument that some sort of change has indeed occurred? Okay, modern day evolutionists are debating whether the change is indeed slow and incremental or quick with long time periods of stasis in-between (i.e., punctuated equilibrium). But if you look at all the transitional fossils that we have (and there are many), you have to admit that some sort of change has occurred.

Kevin

Kevin said...

Stephanie wrote:
Could it be that the main reason people fail to understand evolution is because they have been taught not to understand evolution?

Exactly! This is a very important point that you have raised. When I was in high school in the ‘90’s, South African schools did not teach the theory of evolution in biology classes. There was no mention of it at all. Sure, we learnt about the anatomy of the hydra; had to draw the organs inside a bird; and had to study the types of enzymes present in the digestive system. But there was no over-arching principle present that linked everything together. Boy, what a struggle I went through when I had to learn the concepts of evolution for the first time when I decided to study Zoology at university!

By the way, Stephanie, do you have a blog up and running?

Kevin

Kevin said...

Kevin Cadman wrote:
You need to learn how to evangelise - you're not going to 'win people for Christ' with such condescension and vehement bigotry.

Hi Kevin

I agree with you.

I have great respect for Christians (or non-Christians) who enter into dialogue and discussion when speaking about religion. Tin Soldier and Roger are two frequent Christian posters on my blog who I enjoy interacting with. I also have a friend who is a young earth creationist. Sometimes when we meet with each other we enter into discussions on the whole creation vs evolution debate. However, what I respect most about my friend (and what I respect most about Roger and Tin Soldier) is they are not interacting with me with the primary goal of saving my soul. Rather, they are entering dialogue with the goal of discussion and of learning something new. They sometimes point out flaws in my arguments, and sometimes they accept valid points that I might bring up.

However, I find it difficult to suppress some irritation of those who try and evangelise to me with the sole purpose of saving my soul (did I just write a pun?). The above attempt of Greg’s is much worse that the terrible EE3 (Evangelistic Explosion) technique: “If you would die tonight and stand before God, and God were to ask you, ‘Why should I let you into my heaven?” what would you say?”. . .

Kevin

Anonymous said...

Hi Kevin,

I really enjoy your blog. I am new to blogging and have just visited a few blogs, but I do not have my own blog yet. Agnostic Mom was the first blog I found and then I found your blog through hers. Thanks for the great insights and book reviews.

Stephanie

Anonymous said...

Dear Kevin,

This is my first comment on your blog - I've been reading through a few of your blog entries, and particularly the dialogue between yourself and Roger Saner has been helping me figure some things out for myself. I am a Christian, and to all who can't see inside my head, a faithful, certain, and devoted one. However, particularly at the moment, and to a lesser degree, for a number of years, I have always struggled with doubt. It feels like a curse sometimes - like when I scream at God, wanting to believe easily, but always having some question rise up - and a blessing at others - keeping me honest. But that is a bit off track.

I found it interesting in reading this entry, that you only dealt with the second reason we find evolution difficult to grasp - the micro to macro issue. To me that is less of an issue than the first reason, and I quote from your entry:

First, humans are successful creative designers. So much so that we are predisposed to the idea that complex elegance is an indication of purposeful design. Evolution is counter-intuitive in this sense.

That is close to where I stand. No matter how many doubts assail me, I cannot get away from the , to me, indisputable fact that this world could not have just happened randomly. There had to be a designer somewhere, and I'm happy to call that designer God. Now whether that is the same God as the Bible is another question which I won't get into now. But the designer of the world to me warrants the title of "God." And how did this God choose to implement his design? Well, this is where I differ from my fundamental Christian brothers and sisters - why couldn't he have used evolution as a mechanism to carry out his incredible design? I actually reckon that is an even more awesome feat than creating the world in 6 literal days, like some kid with a bunch of plasticine - blob to shape in one easy swipe. The intricate process is incredible I reckon.

But I digress - I was wondering if you had any response to this first reason evolution is hard for the average human to grasp?

btw - attitude's like that of Greg's are one reason I struggle with doubt........ sorry my fellow Christians can be so high and mighty and closed minded. I look forward to more intelligent, thought provoking dialogue.

Cathy.

Anonymous said...

Hi Kevin,

Me again. I just found your May 2007 entry - Purpose Inherent or Purpose Imposed? So you have addressed the first reason after all. But I'm still up for any further comments you might have : )

Cathy.