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Archive June 2010

evolution vs creationism: the ‘discussion’ continues Alison Campbell Jun 11

3 Comments

I’ve heard back from my correspondent on evolution. While I suspect we’re talking at cross-purposes & will probably continue to do so, it’s worth continuing to address his arguments.

Thank you for responce to my email. I’m disappointed (but not surprised) that none of your answers is anything more than “reasonings” (a big word for “guesses”).

Well, no – ‘reasonings’ is not a ‘big word’ for ‘guesses’. A guess is just that, an off-the-cuff suggestion. ‘Reasonings’ are based on reason i.e. they’re evidence-based.
 
You have the academic’s gift of not using one word where twenty will do.   Gotta love your “The Theory of Evolution [explains] …. the mechanics of evolution”. (ha ha ha)
 
For presentation I’d give you 26/33; for reasoning 18/33 and for factuality 4/33 = 48/100 = C. 
 
Leaving aside what’s really a bit of an ad hominem, this comment continues to reflect a misunderstanding of just constitutes a scientific theory. A theory is an explanation for a large body of observational data (‘facts’, if you like), one that allows us to make testable predictions. In the case of evolution, the data come from a range of sources (including palaeontology, embryology, geology, molecular biology) & the theory provides an explanation for these data. Darwin’s original theory of evolution posited natural selection as the mechanism by which evolution occurred – these days that would be joined by genetic drift as well.
 
Believers in evolution put their faith in the idea that: (a) Their opinions constitute “facts”.
 
(b) Their (relative) goodness is sufficient to absolve them from their wrongdoings.
 
Again, this (statement ‘a’) reflects a misunderstanding of how science works. Scientists don’t think that their opinions constitute ‘facts’. Scientists’ understanding of the world is based on facts – they collect data (from observation & experiment) & try very hard indeed to ensure that their collection methods are not biased by a priori assumptions or opinions about what they might find.
 
I’m also a bit leery of claims to ‘believe’ in evolution. From my perspective the theory of evolution represents the best currently-available scientific explanation for the origins & development of the diversity of life. This is not a belief but an evidence-based understanding.
 
As for (b) above – this is a straw-man argument. I don’t know anyone working in evolutionary biology who holds such a belief. I don’t presume to speak for them, but for myself – I see no need for some external agency to ‘absolve’ me from anything (I’m my own best [worst?] critic if I think I’ve done something reprehensible). Nor do I need that external agency to keep an eye on me to ensure that I’m ‘good’. Living by the precept of doing to others as I would have them do to me provides an internalised moral guideline for ethical behaviour.
 
Denial that such beliefs do not constitute a (humanistic) religion does not stop Evolution from being a religion.    Faith in the idea that your great-great-great etc grandma was a turnip is still faith.
 
Sorry, but this is simply setting up another straw man – a complete misrepresentation of how evolutionary biologists view the world. None of us would view the turnip–>human suggestion as anything but a joke (not least because turnips & humans are both modern species & their last common ancestor - which would have lived a very long time ago indeed – would have looked nothing like either of them). However, there is substantial evidence for evolutionary relationships between species: for example, in support of the statement that humans and chimpanzees last shared a common ancestor between 5 & 7 million years ago.
 
Creation did not “make itself”. We are, instead, the handiwork of the Eternal. Of these two options, the first lacks:   logic, order, purpose and hope. In God, life has:   meaning, direction, structure, and value.
 
I agree that in general life doesn’t have ‘purpose’ in the sense of being here ‘for’ some particular reason. But it’s wrong to say that lack of religious belief means that an individual’s life can have no logic, order, purpose or hope. People tend to live orderly lives – in fact, as ‘pattern-seeking’ animals it would be a bit surprising if we didn’t. I don’t think that I’m here for some purpose ordained by an external agency, but I do feel that my life is purposeful, in the sense of working towards self-determined goals (ensuring our children grow up healthy & have the best start in life we can give them, for example). Of course I have hopes, for them & for us & for others - why on earth shouldn’t I? The fact that my life, as I understand it, will be over when I die doesn’t mean that I can’t have hope for the future of those who come after me!
 
I realise that the choice for you is hard. You can continue to benefit from continuing as a Professor …. or seek a new life with God (see Mathew 10:32-33).
 
Thank you, but it’s not a hard choice at all. I will continue to live my life as best I can, treating others as I would hope they would treat me, and glorying in the wonders of the world that science can reveal.  

i get more mail – belief in evolution allows me to ignore my sins Alison Campbell Jun 09

8 Comments

I’ve had another e-mail – with the fastest invocation of Godwin’s Law that I can remember seeing in a while:

I am horrified to find that neo-Darwinists have hijacked the New Zealand Science Syllabus and are now using it to propogate their religion. As a Christian minister, I’m alarmed that the Atheists, Bioethicists and Nazi Apologists are supported by New Zealand taxpayers to advance their theories as “facts”.
 

The intention here is to smear by association: we’re pretty much all in agreement that much that was done in the service of the 3rd Reich was evil, so if Nazis are associated with evolution, that must be evil too. Which is total nonsense. Hitler didn’t invoke Darwin. And if he had? It doesn’t make evolution wrong, any more than if Darwin had recanted on his deathbed (he didn’t).

My correspondent also seems to misunderstand the nature of ‘facts’ & ‘theories’ in science. In this case evolution is both a fact and a theory. We have ample evidence that evolution has occurred (& is occurred) – this lets us view it as a fact. The theory of evolution is the explanation for those facts. (PS At this point I should have added – & will now – that evolutionary theory is not a ‘religion’. It’s science & thus evidence-based. Religion is a matter of personal faith.)

Now that’s out of my system… My correspondent went on to make several ‘points’:

What renders Evolution as problematic (even as a tool of the Divine) is that:
 
(a)  It does not stand up to examination (see article below)
 
(b)  All of life is discrete, being “after their own kind”.
 
(c)  The fossil record shows so much of life “appearing” (and) over a relatively short time.
 

The ‘article’ mentioned here is a compendium of the usual misunderstandings & misconceptions about evolution, which I may go on to talk about in another post. For b) – the misconception here is that there are no transitional forms; we never see a crocoduck (or an owlcat), for example. I’ve addressed that one previously.

And on c) – remember here that the ‘relatively short time’ is in fact millions of years. Even the Cambrian ‘explosion’ occurred over perhaps 30 million years. (Part of the problem with this one, for many people, may be that such timespans are almost impossible to conceptualise.) The term ‘explosion’ is in fact something of a misnomer. DNA data, for example, suggest that many animal lineages go a lot further back, & there are what appear to be animal embryos that date back around 700 million years or so.

As you will know, there are those Christians that are inclined to believe the Genesis 1 account is correctly rendered “days” and those that don’t, prefering “aeons”.
 
Neither belief is fatal to the idea of God as Creator, so:
 
(d) Creationism (in whatever form) gives an account for creation.
 
(e) Evolution gives no such account …… leaving only the supposition that non-existence created existence.  That is Magic, not Science.
 

Creationism ‘gives an account for creation’ only to the extent that the Biblical creation tale is just that: an account written much later than the postulated events it describes. (We need to remember that there are actually 2 creation tales, Genesis 1 & Genesis 2; my correspondent mentions only Genesis 1 but why should this one be any more correct than the other?) The other issue here is that other faiths have different creation stories, so who decides which is ‘right’?

Evolution doesn’t give an account for creation – but then, Genesis (either version) conflates creation of the universe & the world with creation of species. Evolution deals with living things & to suggest that evolutionary biologists say otherwise is to create a ‘straw man’. The theory of evolution cannot explain the origins of the universe. It can, however, provide a mechanism to explain the evolution of living things from the point at which life first appeared. (‘Life’ being a fairly loose term: if we take it as something capable of self-replication then we could be considering an RNA world.)

I can understand that you would want there to be no God….. since that would do away with Absolute Truth and leave you not guilty of your sins. 
 
Without God there is just the random stuff of Phenomenology and so no ultimate Right and Wrong.   That is simply a delusion to avoid facing the idea that “the soul that sinneth, shall die”.
 

We’re getting a long way from my usual blog topics now (& into Ken’s territory). .. But my correspondent is wrong to say that I ‘want’ there to be no God. That’s putting words into my mouth (another straw-man argument). From my perspective: personally I see no objective evidence that there is a God. What’s more, the question of any god’s existence one that science can address, since science doesn’t deal in the supernatural. (Nor does science deal in absolutes.)

Nor can I understand the need for some external, all-powerful arbiter of right & wrong. It’s perfectly possible to behave in an ethical fashion towards others without worrying about the ultimate consequences of what will happen if we behave badly, & in fact many people do just that, applying what you could call the ‘golden rule’: treat others as you would like them to treat you. It’s also quite likely that there is an evolutionary basis for human morality.

I’ll finish by pointing out that lack of belief in a deity doesn’t mean that I must feel that my life lacks meaning, or hope, nor does it mean that I can’t see the beauty of the world around me. As Richard Dawkins has said:

The feeling of awed wonder that science can give us is one of the highest experiences of which the human psyche is capable. It is a deep aesthetic passion to rank with the finest that music and poetry can deliver. It is truly one of the things that make life worth living and it does so, if anything, more effectively if it convinces us that the time we have for living is quite finite. (from Unweaving the Rainbow, 1998)

reflecting on teaching (& learning) about the nature of science Alison Campbell Jun 06

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This is a re-post of something I originally wrote for the ‘other’ blog that I share with Marcus & Fabiana.

A couple of days ago I took part in a discussion around reflective writing. It was organised by the University’s Student Learning Support team, with the intention of helping students working towards their PhDs to think – in a reflective way – about what they are writing. I was asked along because the organisers felt that some of my blog posts were a good example of reflective writing – showing in my writing how my thoughts about a particular topic develop. (This is the example they chose as a basis for the discussion.) It was an interesting & productive session, & I think I probably learned as much as the students (albeit about different things).

One of the students asked me how thinking about science & reflecting on research affected my teaching. There followed a brief pause for thought :-)

To my mind (I said), thinking about science must surely include thinking about the nature of science – & from there, to thinking about how we teach about the nature of science. This isn’t just idle day-dreaming: if someone is going on to a career in science, then I’d like to think that they have more than a passing understanding of what science actually is. This is something that the new NZ school science curriculum is intended to address (although, realistically, I believe teachers are going to need a lot more support & guidance in doing this). But at university, how do we teach our students about the nature of science? Or, more to the point, how are we going to help them learn about it? For sure, that learning is not going to be on the basis of ‘cook-book’ lab exercises, where students basically follow a recipe to a pre-determined end. (The tutor & I are seriously trying to move away from this, in our first-year bio labs. But that’s another story – perhaps, one that I should persuade her write about here…) We need to give them a lot more opportunities to think like scientists, & to reflect on how science is done.

Standard, ‘traditional’ teaching methods don’t achieve this particularly well. There’s an increasing body of evidence out there that shows this. That student’s original question reminded me of some work I did with a couple of colleagues (& we really must publish it!) looking at how well our students understood the nature of science. To our suprise – & concern – we found that our 3rd-year students had no better grasp of it than the first-years we surveyed. Of course those 3rd-years had a lot more scientific knowledge, but they were still quite shaky on how science worked. To me, this means that we need to be a lot more up-front in teaching the nature of science, & certainly this realisation had quite an impact on my own classroom practice.

Reworking labs is one way to give students more opportunity to ‘do’ some meaningful science, but I firmly believe you can give students the opportunity to practice thinking like scientists in lecture & tutorial classes as well. This is where some of the active engagement techniques I’ve written about earlier come into play. However, ‘thinking like a scientist’ isn’t something that’s picked up by osmosis – we also need to model how it’s done. Those of you who read my ‘other’ blog will know that I’m big on stories as a way of illustrating the way scientists develop their understanding of the world. As I said there, telling the occasional story lets students see scientists as people who are thinking; speculating – saying ‘what if?’; using hypotheses, looking at evidence, ultimately making those strong explanatory theories that tie it all together. They’re thinking creatively: science is a creative process & at its best involves imagination & creativity. They make mistakes! Most of the time we’re wrong but you don’t get to hear about that because it doesn’t make good journal articles; usually no-one publishes negative results. So you just hear about the ‘correct’ stuff. Scientists persist when challenged, when things aren’t always working well. And so on.

Another way to model ‘being a scientist’ for students is to actively show them how you arrive at an hypothesis or the answer to a question. I actively encourage students to ask questions in lectures (& it’s a given that this’ll happen in tutorials) – how else am I to know what they don’t understand, or whether I’ve explained something clearly enough. From time to time, someone will ask a question to which I don’t actually know the answer. (And reflecting on it -  :-) – this is one of the things that I really enjoy about teaching, because it spurs me to go and learn something new!)  And I’ll tell the class that, that I don’t know. They need to know that scientists aren’t infallible, that we don’t know all the answers. (The idea that scientists ‘know it all’, or think they do, is a fairly pervasive one in the media & not one that does us any favours.) But then, I’ll say: but this is what the answer might be, and this is how I arrive at that hypothesis – the information I’m basing my answer on, how it all fits together & so on. In other words, I model my thought processes for them.  Sometimes they’ll call me on that & propose their own explanations. And then, between that class & the next, I’ll go off & see what I can find in the literature that will let me give a better answer – or if it’s a tutorial class we might look it up on the spot, it depends how we’re going for time. (Occasionally someone in the class will do that too – remember, these are first-year students & I think for many of them the prospect of maybe showing me I have got things wrong is more than a little daunting…) Then I can put the information on-line via Moodle, or use it to kick off the next lecture, & hopefully we’ve all gained something from it.

I hope all that helped the ‘reflective writing’ group; that they could take something from it to inform their own thinking & reviews of their work. I know that the reflection spurred by their initial questions, certainly helped me.

acupuncture & adenosine Alison Campbell Jun 03

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A couple of days ago the morning paper carried a story about acupuncture. More specifically, a story saying that researchers had shown how acupuncture works to reduce pain. The study was done in mice (& so presumably used very small needles) & found that ‘needling’ was followed by release of adenosine, a substance which has been known for some time to reduce sensations of pain.

It sounded interesting & I filed it away mentally for further examination. Unfortunately time is passing & I haven’t a huge amount of it to spare. Fortunately Orac has done his usual thorough job of reviewing the original research paper (& identifying some of the more overheated reactions to the publication). So go over there to read his review & join in the discussion :-)

iconography of evolution Alison Campbell Jun 01

1 Comment

You’re probably fairly familiar with some of the iconography associated with human evolution. Here’s a frequently-used image:

and there’s another similar one, which uses a visual joke to make a serious point about where dietary habits in the West may lead us.

In fact, there are a lot of these images around:

You can even buy the t-shirt :-)

The trouble, as Stephen Jay Gould remarked in his book Bully for Brontosaurus (& again in Wonderful Life), is that this iconography is wrong, wrong, wrong.

For starters, this imagery tends to exemplify the idea that humanity is the pinnacle of life’s evolution, & that all of evolution has been focused on that end. Evolution doesn’t work like that! It’s not directional, not purposeful or goal-oriented, cannot plan for the future. A more considered look at the evolutionary history of life on Earth shows that we occupy a small twig on the side of the ‘mammal’ branch – the fact that we have affected the environment out of all proportion to our place in nature reflects our generalist nature and the pressures selecting for that oversized lump of grey matter inside our skulls.

I had to search around a bit to find this image. A surprising number of trees look more like this, with ‘our’ branch reaching to the top of the tree & other mammalian scions terminating further down – something that again reinforces the idea of the primacy of humans. This one pretty much avoids that trap, & has all living lineages reaching to the top of the tree. What’s more, it uses the length of an individual branch to convey information about how long ago a particular lineage diverged from its nearest relatives; the oldest line of all originates closest to the base of the trunk.

So, we know that evolution doesn’t occur in a linear fashion but in fits & starts, with new species branching off hither & yon. The straight-line view encapsulated in the images I began with owes more to the idea of a ‘great chain of being’ than it  does to the fascinating reality. This is as true for our own branch as it is for the tree of life itself:

Family tree of early hominids and early humans

Even allowing for a certain amount of splitting & lumping (some palaeanthropologists tend to assign a new binomial name to each new fossil find, while others lean to aggregating the remains into fewer species), our family history is bushier than anticipated by earlier workers in this field. I can still remember being taught this stuff in 7th form (year 13) & having it all presented as if one species followed another in a nice tidy sequence. Even the image above falls into that trap a little, with Homo represented by a single line (as much an artefact of the figure’s scale as anything else).

But even within our own genus there is some branching – evolution on a fractal scale? (Go to the original web page for a key to this, eg 10 = Neanderthals & 11 = ‘us’, & much more besides – well worth it for anyone looking for a very readable intro to the literature on ’Flores man’.)

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