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Posts Tagged creationism

not science as i know it Alison Campbell Feb 06

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By accident,  I came across the curriculum document for Accelerated Christian Education (ACE) which provides teaching & learning materials to parents who are homeschooling their children. New Zealand students who complete the program right  to year 13 gain university entrance.

Home Schooling NZ gives parents advice about the ACE program, but makes it clear that HSNZ does not work for Accelerated Christian Education or sell their teaching & assessment materials.  However, I was startled to see the following listed by HSNZ as one of the ‘distinctives’ [sic] of the ACE program:

Each student is taught from a biblical perspective developing critical thinking skills that will enable them to discern what is truly “…the good and acceptable and perfect will of God.” (Romans 12:2)

Having had a fair bit to do with the development of the Science section of the current national curriculum document, specifically, the Living World component, I was naturally interested in seeing how ACE handles a science curriculum. The answer is, poorly.

In fact, I feel that it’s most unfortunate that the ACE science program is officially recognised here, given statements such as this from Sir Peter Gluckman (the PM’s Chief Science Advisor) about the importance of science and science education. For example, from the curriculum overview material for grade 1 students we learn that students will

  • [pronounce and learn] new vocabulary words as they are defined and used in the text
  • [discover] God’s wisdom as he1 learns about God creating Earth…
  • [learn] about the design and care of the human eye and ear; high, low, soft and loud sounds.
  • [learn] about the importance of personal health – clean teeth and hands.
  • [gain] a respect for God as he learns about God’s wisdom, goodness, kindness, and that all things belong to God.
  • [read] stories and answer questions about God’s creation.
  • [continue] to build eye-hand coordination by drawing shapes, irregular shapes, and directional lines.

That’s it.

In contrast, the New Zealand Curriculum document has a number of subject-specific achievement aims for students at this level, in addition to those relating specifically to the nature of science. For example, students in their first year or two of primary school should

  • Learn about science as a knowledge system: the features of scientific knowledge and the processes by which it is developed; and learn about the ways in which the work of scientists interacts with society.
  • Appreciate that scientists ask questions about our world that lead to investigations and that open-mindedness is important because there may be more than one explanation.
  • Explore and act on issues and questions that link their science learning to their daily living.

Remember, that’s in addition to the achievement aims for biology (Living World), chemistry (Material World), earth sciences (Planet Earth & Beyond). and physics (Physical World).

And so it continues. I mean, how could this (from the ACE objectives for Grade 3) be construed as science by anyone assessing the document?

Studies Bible topics such as Jesus’ return; sin, death, and the curse; man’s freedom to choose to love and obey God.

Or this?

Discovers the Bible to be the final authority in scientific matters.

Science, it ain’t. It would appear that helping students to gain and enhance critical thinking skills isn’t on the curriculum either – after all, teaching students to look to authority for the answers runs completely counter to encouraging critical thinking and teaching students how to weigh up evidence.

While I haven’t read all the PACEs available for the curriculum, partly because I am not going to buy them in order to do so, I have read through the samples available on line. Among other things, the materials I viewed encouraged rote learning rather than deep, meaningful understanding of a subject – a long way indeed from current best-practice models of teaching & learning.

However, others have read ACE’s PACE documents, & have been extremely critical of them. The Times Education Supplement, for example, was startled to find that ACE materials available in 1995 contained the claim that the Loch Ness Monster has been reliably identified and seems to be a plesiosaur. (It seems this reference has since been removed from new textbooks published in Europe.)

The TES also addressed some rather trenchant comments to the UK educational body responsible for giving the ACE curriculum equivalent status to O and A level examinations. Perhaps the NZ equivalent of that body should give the ACE documents a closer second look.

 

1 No female pronouns used, that I could see. (No room for female scientists in this curriculum, either – students are introduced to ‘early men in science’.)

 

 

However, ACE do make a curriculum document available on-line, and the comments that follow are based on this. I am certainly hoping any materials that are sent out to NZ are modified to take account of our different context (for example, the source document talks about nickels & dimes in some maths sections). The Science section begins on page 22 of the linked document. Frankly, I do not think that students who had studied this curriculum would be well-prepared for university study in biology. For example:

an interesting take on mousetrap evolution Alison Campbell Oct 30

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One of the catchphrases of Intelligent Design creationism is ‘irreducible complexity’ – the idea that in some complex biological systems, it’s impossible to remove any one part without causing the whole system to fail. Supposedly this means that such systems could not have evolved but must be the product of a ‘designer’. The term – in its most recent incarnation – was proposed by biochemist Michael Behe, but it’s effectively the same as William Paley’s 19th century concept of the watchmaker.

Behe used to be fond of using the ordinary, bog-standard, everyday mousetrap as an example. I have always found this just a tad unimaginative of him, as while removing (say) the spring would render the mousetrap incapable of doing its current job, this is not the same as saying that the remaining parts do not (& cannot) have some other function. (In a better, biological, example various constituent parts of the so-called ‘irreducibly complex’ flagellum bacteria** do actually have other functions, including adhesion to other cells.) I could, for example, throw the wooden platform of our old mousetrap*** at a mouse. Occasionally I might even hit it.

There are other possibilities for mousetrap evolution, described rather amusingly here (& hat-tip to Peter Bowditch of the Millenium Project).

 

** Incidentally, there is no such thing as ‘the’ bacterial flagellum.

*** I say ‘old’ because we haven’t used it for a while. These days the fat (6kg) furry ginger monster does the job quite satisfactorily. He probably falls on them.

 

science: 1; society for textbook revise: 0 Alison Campbell Sep 09

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From Nature (& via a commenter at Silly Beliefs): science wins over creationism.

In South Korea, the Society for Textbook Revise, STR [sic] – associated with the Korea Association for Creation Research – has apparently been pushing textbook publishers to remove two examples of evolution from school textbooks. You may be surprised to hear that we’re not in Texas any more, Dorothy, given how similar this sounds to calls in the US for students to learn about the ‘theories’ around the development of life on earth. The STR argued that because scientists were ‘debating’ the two textbook examples (Archaeopteryx, and the evolutionary history of horses), the examples were ‘flawed’ & so shouldn’t be taught. (Which, at the very least, shows a misunderstanding of how science operates.)

Soo Bin Park reports in Nature that, initially, the textbook publishers were going to do as STR wanted; however, following an outcry from scientists, the South Korean government set up an expert panel to look into the issue. The outcome?

A reaffirmation that

the theory of evolution is an essential part of modern science that all students must learn in school

and that Archaeopteryx should be retained in the texts.  Regarding the horse example, the panel commented that the textbooks presented it in ‘too simplistic’ a manner and that it should be revised or replaced, perhaps with an explanation of cetaceans’ evolutionary history. This did make me wonder if perhaps the books’ authors had gone down the route of what the late, great Stephen Jay Gould described as the ‘fox terrier problem’ and the ‘creeping fox terrier clone’.

In other words, had they used the ‘traditional’ iconography where the evolutionary history of modern horses is presented in a fairly linear fashion, from the little Hyracotherium (I still prefer the lovely name Eohippus!) to modern Equus, with only 2-3 intermediaries? We now know that the horse phylogeny is more complex than that. And, had they described Hyracotherium as ‘about the size of a fox terrier’, something that Gould found to be repeated in just about every book he (well, his research assistant) looked at? It turns out that the fox terrier would have been a rather large one: Eohippus/Hyracotherium was about 60cm long & 20cm at the shoulder, and weighed around 22kg – more like a small labrador!

Incidentally, those two names reflect the way this species was named. Hyracotherium was first described – on the basis of an incomplete specimen – by the English anatomist and palaeontologist, Richard Owen. Subsequently the American palaeontologist Othniel Marsh found a complete skeleton and named it Eohippus. Subsequent comparison found the two specimens belonged to the same species, and Owen’s name was applied to both under the rule of priority used in scientific taxonomy. (Brontosaurus went the same way, replaced by the older – but, to me anyway, less euphonious Apatosaurus.)

S.B.Park (2012) Science wins over creationism in South Korea. Nature published on-line): doi: 10.1038/nature.2012.11377

 

quality counts – except when it doesn’t Alison Campbell Aug 06

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A few weeks ago, writing about the ‘great class size debate’, I also touched on the question of quality teaching. There’s no question – at least, there shouldn’t be – that children deserve the best possible learning experiences, and one of the requirements for that is quality teaching by excellent, expert teachers. It’s quite tricky to pin down just what defines that excellence, but at least our current system of state sector teacher training and subsequent registration goes some way to ensuring that the people teaching our youngsters have been trained in how to go about the multitude of tasks that teachers encounter every day: planning, classroom management, assessment, pastoral care & general admin, and have gained experience in said tasks…. (and that’s before we even get to the actual teaching!).

But a couple of days ago, Minister of Education Hekia Parata & Act MP John Banks announced that charter schools – oops, sorry, ‘partnership schools’ – would be able to employ at least some non-registered teachers, along with setting their own curricula & deciding on things like the length of the school day, term dates, & teacher pay rates. This is strange – to say the least! – following as it does on a recent meeting of the Ministerial Cross-Sector Forum on Raising achievement, which “discussed… improving teaching practice with a focus on priority learners.” As well that discussion, the meeting heard from the Chief Education Review Officer, who

presented the latest Education Review Office findings on how to raise the quality of practice in New Zealand Schools.

His remarks focused on three dimensions: assessment for learning; student centred learning; and responsive school level curriculum.

Minister Parata, who chairs the Forum, commented that

The Forum will continue to discuss ideas around how we can achieve quality teaching practice.

It’s not exactly clear how allowing charter schools to use some unspecified proportion of non-registered teachers will achieve this. Concepts and practices related to assessment for learning and student-centred learning are best acquired before arrival in the classroom, not on a learn-as-you-go-when-you get-there basis. (Yes, state schools can already employ non-registered staff, under a ‘limited authority to teach’ provision, but that’s temporary and for a limited period.)

Some real contradictions here…

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The freedom of charter schools to set their own curriculum also concerns me somewhat. We already have ‘special character’ schools which teach creationism in their classrooms, for example (see here, here, and here, for starters). It is rather irking to gain the impression that state funding could support the same in charter schools – and to date I’ve heard nothing to say this will not be possible.

 

 

if evolution is true, why are there still apes Alison Campbell Apr 11

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We’ve just come back from a few glorious days in New Plymouth (arriving home before the change in weather). Had a great time tramping, walking the coastal walkway, eating yummy food – all those nice things you do, holidaying with friends. And as some of the party were driving from Paritutu to meet the rest of us at an outdoor cafe on the coastal walkway, they saw the following sign:

why are there still apes.jpg

It’s a variant on the old “if men evolved from monkeys, why are there still monkeys”, only slightly more accurate – in the sense that we are much more closely related to apes than we are to monkeys, lol. But both versions are wrong, based on a misunderstanding on the nature of evolution, and I wonder if the sign’s author would be willing to look at the evidence for the real state of affairs.

For we didn’t evolve ‘from’ modern apes. In taxonomic terms, humans are apes: placed in the primate sub-order Anthropoidea along with gorillas, chimpanzees & bonobos, orangutans, & gibbons. Morphological & DNA evidence indicates that our nearest living relatives are the chimpanzees, with whom we last shared a common ancestor around 6 million years ago. At 4.4 million years old, Ardipithecus ramidus is the oldest known hominin – & it wasn’t particularly chimp-like. Which is hardly surprising, as the ancestors of both humans and chimps/bonobos have been following separate evolutionary trajectories for all that time. As the team who discovered and described ‘Ardi’ have commented (White et al., 2009):

Perhaps the most critical single implication of Ar.ramidus is its reaffirmation of Darwin’s appreciation: humans did not evolve from chimpanzees but rather through a series of progenitors starting from a distant common ancestor that once occupied the ancient forests of the African Miocene.

T.D.White, B.Asfaw, Y.Beyene, Y.Haile-Selassie, C.Owen Lovejoy, G.Suwa & G.WoldeGabriel (2009) Ardipithecus ramidus and the palaeobiology of early hominids. Science 326: 64 (authors’ summary**) & 75-86. doi: 10.1126/science.1175802

** Teachers – the summary would be a good introductory read for your senior students.


‘scientists anonymous (nz)’ write again… Alison Campbell Mar 26

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I’ve written about the group who call themselves ‘Scientists Anonymous (NZ)’ before, in the context of determining the reliability of sources. At the time, I commented that I would have a little more confidence about the information this group was putting out there if the people involved were actually identified – as it is, they are simply asking us to accept an argument from (anonymous) authoriry. (I was rather surprised to actually receive a response to that post, albeit its authors remained anonymous.) Anyway, this popped up in my inbox the other day, and was subsequently sent to me by several colleagues in secondary schools:

TO: Faculty Head of Science / Head of Biology Department

Please find a link to the critically acclaimed resource (http://programmingoflife.com/watch-the-video) dealing with the nature of science across disciplines/strands.

Interesting to see an attempt to link it into the current NZ Science curriculum with its focus on teaching the nature of science.

PROGRAMMING OF LIFE

  • The reality of computer hardware and software in life
  • The probabilities of a self-replicating cell and a properly folded protein
  • Low probability and operational impossibility
  • The need for choice contingency of functional information

Freely share this resource with the teaching staff in your faculty/department.

Yours sincerely

Scientists Anonymous (NZ)

So, I have been to the website. I intend to watch the video tonight (from a comfy chair), but the website itself raises enough concerns, so I’ll look at some of them briefly here. And I’ll also comment – if they really are ‘doing science’, then it’s not going to be enough to simply produce a list of ‘examples’ of the supposed work of a design entity (because that’s what all the computing imagery is intended to convey) & say, see, evolution’s wrong. That would be an example of a false dichotomy, & not scientific at all. They also need to provide an explanation of how their version of reality might come to be.

Its blurb describes the video as follows:

Programming of Life is a 45-minute documentary created to engage our scientific community in order to encourage forward thinking. It looks into scientific theories “scientifically”. It examines the heavy weight [sic] theory of origins, the chemical and biological theory of evolution, and asks the extremely difficult questions in order to reveal undirected natural process for what it is – a hindrance to true science.

The words ‘undirected natural process’ immediately suggest that this is a resource intended to promote a creationist world-view. I would also ask: if the documentary is created to ‘engage our scientific community’, then why did Scientists Anonymous send it to secondary school teachers in biology and not to universities & CRIs across the country? The blurb goes on:

This video and the book it was inspired by (Programming of Life) is about science and it is our hope that it will be evaluated based on scientific principals [sic] and not philosophical beliefs.

Unfortunate, then, that they wear their own philosophical beliefs so clearly: ‘undirected natural process’ as a ‘hindrance to true science’.

As well as linking to the trailer for the video, & the full video itself, the Programming for Life website also presents a bunch of ‘tasters’. One of these is the now rather hoary example of the bacterial flagellum (irreducible complextiy, anyone?) The website describes ‘the’** flagellum thusly:

The bacterial flagellum is a motor-propeller organelle, “a microscopic rotary engine that contains parts known from human technology such as a rotor, a stator, a propellor, a u-joint and an engine yet it functions at a level of complexity that dwarfs any motor that we could produce today. Some scientists view the bacterial flagellum as one of the best known examples of an irreducibly complex system. This is a single system composed of several well-matched, interacting parts manufactured from over 40 proteins that contribute to basic function, where the removal of any one of those parts causes the entire system to fail.

** As noted on my link for this example, there is no such thing as “the” bacterial flagellum as the sole means of bacterial locomotion: different prokaryotes get around in different ways. Nor is the flagellum a case of design; its evolutionary history has been quite well explained. The lack of quote closure (& of citation) is in the original.

Mitochondria have their own executable DNA programs built in to accomplish their tasks.

Well, yes, & no. Several key mitochondrial genes are actually found in the cell’s nucleus – something that allows the cell to control some aspects of mitochondrial functioning (& incidentally prevents the mitochondria from leaving!). There’s a good review article here. That the number of nuclear-based mitochondrial genes differs between taxa is a good argument for evolution; for design – not so much.

Much like the firewall software on your computer the membrane contains protein gate keepers allowing only those components into the cell that belong and rejects all other components. The membrane is thinner than a spider’s web and must function precisely or the cell will die.

Well, d’oh – except when it doesn’t. Viruses, and poisons that interrupt cellular metabolism, get in just fine. They really are pushing the boundary with this computer metaphor.

The human eye is presented as an amazingly complex ‘machine’ – yet we have a good explanation for how that complexity evolved. And more telling (but omitted from this presentation): the eye’s structure isn’t perfect – it’s a good demonstration of how evolution works with what’s available,but hardly an argument for the wonders of directed design. The same can be said for the human skeleton, which is also in the taster selection, along with the nucleus, DNA, & ribosomes (which come with more, lots more, of the computer software imagery).

As I said earlier, if this video is not simply another example of the use of false dichotomy to ‘disprove’ a point of view with which its authors disagree, it had better provide more than metaphor. That is, I’ll be looking for a strong, evidence-based, cohesive, mechanism by which these various complex features sprang into being. Otherwise, we’re not really talking ‘nature of science’ at all.

_______________________________________________________________________________

I was going to stop there (for now) but then I noticed the ‘Investigate the facts’ heading. It links to a list of various papers & articles that supposedly support the ‘design’ hypothesis. Richard Dawkins’ name caught my eye – he’s there for writing that

Human DNA is like a computer program, but far, far more advanced than any software we’ve ever created.

I had a couple of thoughts; a) metaphor is a wonderful thing, & b) Dawkins is a biologist & science communicator, but not necessarily big on programming. (If I am inadvertently doing him a disservice, I apologise!). Someone else had the same thoughts.

videos on creationism & evolution Alison Campbell Feb 29

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A while back, I wrote about the way that the geology of the Grand Canyon has been misrepresented by ‘Young Earth’ creationists. Now here’s a good discussion of this from geologist Steve Newton:

You may also remember the comments about evolution that were made by some of last year’s Miss USA contestants. A 2012 Darwin Day talk by Josh Rosenau looks at how closely the contestants’ views match those of Americans in general. His context is the continuing efforts to see various ‘flavours’ of creationism taught in science classrooms.

Both are interesting viewing & could form the basis of some good classroom discussion :-)

letters to the editor: science & god Alison Campbell Dec 20

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From today’s “Letters to the Editor” in today’s NZ Herald:

Your correspondent correctly states that Charles Darwin’s theory of evolution is under threat.

The main threat, however, is not coming from “conservative religious school.” It is coming from science.

Well, as a scientist, this is news to me. What scientific evidence does our correspondent present in support of this supposed ‘threat’?

In the past decade, especially, incredible advances in micro-imaging have revealed the amazing interior of our body’s cells among many other biological wonders. The stupendous complexity of these microscopic structures is leaving scientists flabbergasted.

None of the biologists I know could be described as ‘flabbergasted’ (adj: “overwhelm[ed] with shock, surprise, or wonder“) as they learn more of the cell’s fine internal structures. Not in what I suspect is our writer’s intended sense, of being so shocked & surprised that they’re ready to throw out all they know about evolution & how it functions. (I wonder if by ‘micro-imaging’ he means videos like this one, which is an animation developed by XVIVO for Harvard University.)

Just as a taster, Google “bacterial flagellum” and discover an acid-powered motor inside the cell with a shaft through the cell wall fitted with a propeller that moves the cell about.

I did – & the first entry on the search page is this one from Wikipedia, which gives a clear, factual description of the current state of knowledge of flagellum structure and function. Incidentally, the flagellum evolved at least three times, in Archaea and the ‘true’ bacteria, and in eukaryotes (the group that includes plants, animals, fungi, & single-celled organisms) – you have to wonder why our writer’s designer would tinker like that…

His description of the ‘motor’ is intriguing. The ‘acid-powered motor’ is a complex of proteins, & its movement is powered by the movement of hydrogen ions across a membrane (in the same way that production of ATP in mitochondria uses movement of H+ ions). The word ‘propeller’ may be intended to conjure up images of a boat’s propeller (with all its connotations of a designer), but the flagellum looks nothing like that.

While we’re on the flagellum, our writer seems unaware that the idea that this example of ‘intelligent design’ was comprehensively dismissed during the ‘Dover trial‘. Yes, I know he doesn’t come out and use those words or the term ‘specified complexity’ (hinted at in his next paragraph), but his intent is clear – there’s a designer. Ken Miller has written a clear overview of the whole argument about flagellal origins.

Mathematicians have determined there is no way that such complex structures could accidentally self-form, as required by Darwin’s theory, within the entire life of the universe, let alone in a paltry few millions of years.

Which mathematicians? Jason Rosenhouse has written an interesting post on the issue of improbability & evolution. He notes that those espousing our writer’s view “typically toss off combinatorial arguments in which the probability of evolving some complex molecule, like haemoglobin, is taken to be one over the number of ways of arranging the amino acids in that molecule. Sadly, that only works if all of those arrangements are equiprobable, but the continuing action of natural selection ensures that they are not.” And this is another point where the letter’s author goes wrong, because the process of natural selection is not ‘accidental‘. (He also seems unaware of the antiquity of life on Earth: bacteria have been around for up to 3.5 billion years – orders of magnitude greater than his ‘paltry few millions.’)

“Origin of Species”, written 150 years ago by Darwin, is incorrect and we must be more open-minded when teaching children how we might have got here.

Of course there were things Darwin didn’t know – in the absence of any knowledge of genetics, or of cell ultrastructure, at the time when he was writing, how could it be otherwise? But this does not detract from his magnificent insight, meticulously documented, that evolution by the process of natural selection could account for life’s wonderful diversity. That concept has been tested, and confirmed, and extended, time and time again since the Origin was first published.

There’s an important point to be made here. Just because science can’t currently explain something, does not mean scientists won’t be able to explain that phenomenon in the future. If the response to something novel was always “I can’t imagine how that might develop, therefore God”, then we would never have reached anything like our current understanding of how the living world operates. And we would be the poorer for it.

what about genetic evidence linking us to chimpanzees Alison Campbell Dec 07

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As Grant said earlier, there is a rich mine of potential posts in this particular website... This time, let’s review its author’s take on the phylogenetic relationship between Homo sapiens and Pan troglodytes.

We are indeed linked to chimpanzees — by a common Designer.

Evidence, please! One detects a rather sweeping a priori assumption here.

Even bananas have 90% the same DNA as chimps.

Er, no – the DNA correspondence is closer to 50%. Would be nice to see them get the occasional fact right. Even if the 90% figure were correct, the nature of the 10% difference would be more interesting.

Most of DNA code controls processes within the cell and are common to all living things.

Ah, those pesky facts! (Not to mention the grammar…) A considerable portion of the human genome is neither coding nor regulatory. Although one would have to concede that DNA does control/influence ‘processes within the cell’…

As all DNA is designed by the same Designer

There’s that little a priori thing again…

for the same purpose, we expect it to be similar. We agree with the evolutionist that chimps are closer to use than any other animal, but some animal has to be,

Why? If we’re assuming a series of special creation events, then why would there be degrees of relatedness at all??

and it is not surprising that over 98% of chimp DNA is the same as ours.

But take care with similarities in the design of animals. All DNA is designed by the same designer.

Can we say a priori? Yes, we can…

If the common ancestor theory was true then we would expect the same characteristics to be found coded on the same place on the same chromosome of the different animals.

Unfortunately a fair bit of our DNA can’t have been put there by that supposed designer – just look at endogenous retroviruses (ERVs), scattered throughout our genome. Not to mention the fact that both ERVs and pseudogenes common to several branches of a lineage have accumulated variation that differs from branch to branch. In other words, neither ERVs nor pseudogenes could have been part of that claimed ‘design’.

Even though our knowledge of gene mapping is in its infancy, it is already clear that this expected pattern is regularly not the case. A particular gene on one of our chromosomes may be at an entirely different place on the chimp’s chromosomes. By the way, we have 46 chromosomes and the chimps have 48. Perhaps we are more closely related to the tea tree which also has 46 chromosomes.

Yes, & we can be fairly sure what underlies the difference in chromosome number between chimp & human. Apart from Homo sapiens, all the great apes have 24 pairs of chromosomes. We have 23. The simplest explanation for the available evidence is that the human chromosome 2 originated through the fusion of two of the ape chromosomes: banding sequences match, & the remains of chimp telomere sequences are found in the middle of human chromosome 2 – right where the fusion hypothesis would predict them to be. (We can safely ignore the silly tea tree suggestion. Quite a few animal species have 2N = 46; it doesn’t tell us anything about relatedness.)

The relatively new technique of using genetic similarities to determine how long ago two species or sub-species had a common ancestor is horribly flawed. The time scale assumes a constant rate of genetic variation. But genetic variation has slowed down dramatically over the ages as natural selection processes reduce genetic potential.

Citations please. This statement suggests a woeful lack of understanding of how genetic variation is generated. Mind you, it fits with the statement elsewhere on the school’s website that organisms were created with the maximum amount of genetic variation & it’s all been downhill ever since.

Some animals, eg: the Cheetah, now have almost no genetic variation and therefore no potential to vary any more . The genetic variation which now takes place in genetically separated populations of the same species is very slow compared to what takes place, and has taken place, when genetically rich individuals adapt into new environmental niches. Therefore the time scale of technique is horribly exaggerated.

Again, citations, please! Cheetahs are known to have gone through a genetic bottleneck (maybe two) – with only a few individuals surviving that, it’s no surprise that the genetic variation remaining in the population is severely restricted. As for the next sentence – how do they know, or is this simply an example of making stuff up to suit prior conceptions of reality? They seem to have a really weird concept of what ‘genetic variation actually means…) The time scale of a ticking genetic clock based on the rate of accumulation of mutations is certainly based on some assumptions about the rate – but it’s also capable of being checked against evidence from other sources. For example, the genetic clock suggests that humans & chimps last shared a common ancestor somewhere around 5-7 million years ago – something that’s supported by the available (& increasing) fossil evidence from early hominin remains.

That reminds me, I should have a look at what they say about our own evolutionary history…

what about archaeopteryx? Alison Campbell Nov 21

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As a distraction (or should that be ‘procrastination’?) from what’s currently filling up my diary (ie processing student enrolments), I’ve decided to look at another of those ‘science’ statements from the school documents I linked to in my last post. “What about the archeopteryx?” they ask. Well, what about it? This, from their webpage:

The archeopteryx is an extinct, unusual bird. Two fairly complete skeletons have been found in Europe.

Correct as far as it goes – but there are actually eleven specimens, including an isolated feather also attributed to Archaeopteryx. Interestingly, one of those specimens was originally identified as the small maniraptorian dinosaur Compsognathus on the basis of its skeletal remains (its feathers were poorly preserved & not noticed by the original excavator).

Unlike “modern birds” it had teeth set in sockets, claws on the ends of its wings (although the hoatzin in South America still does today), and a stronger than usual pelvic bone. However it also had muscle attachments (skeletons can reveal a lot) consistent with strong flying (like a raptor today), feathers, and strong talons.

Archaeopteryx also had a long, bony tail; no large, projecting keel associated with the sternum (& a keel is the place where birds’ big flight muscles are attached); and little fusion of bones in the spine & limb girdles. It didn’t have the horny (keratinised) bill that you see in birds. And that pelvic bone (girdle?) may have been strong but its morphology is like that of dromeosaurs, not birds. The point at which the head attaches to the spine, and the form of the cervical vertebrae, is also reptilian, not avian. Yes, skeletons can reveal a lot, and what this (partial) list shows is that, while Archaeopteryx had a number of features we normally associate with birds – most notably, its feathers – it also possessed a large number of features that link it to reptiles and, more particularly, to theropod dinosaurs. It is, in other words, an example of a transitional form.

As for the strong flight that our website’s authors are arguing for – the relatively flat sternum doesn’t support that. Similarly, modern birds have what are known as uncinate processes on their ribs, which help strengthen the ribcage against the compression stresses generated by flight. Archeopteryx didn’t have those, either…

Modern biology textbooks picture the archaeopteryx as an awkward flier, or even glider, which could run and climb well, as a transitional form between reptiles and birds. This is probably the most famous fossil in the world other than some “ape-men”.

Ooops. I guess they don’t agree with the idea of human evolution either. Anyway, Archeopteryx probably didn’t climb trees on a regular basis: if it did, its wing claws would be worn down – but the fossils’ claws are sharp & unworn. So, when it flew, it would have taken off from the ground.

Firstly, evolution is very short of transitional forms so the most has to be made out of whatever can be found.

Bzzzt! Wrong answer. Look here for a list (by no means complete). The transitional sequence for amphibians is a great exemplar.

Secondly, we know by the muscle attachments and feathers that archaeopteryx was a strong flier, making some pictures in biology texts intentionally deceptive.

See my previous comments. The structure of the primary feathers on Archaeopteryx‘s wing tell us it flew, but the evidence from sternum & ribs suggest that it was not a strong flier – something that Pat Shipman discusses at some length in her book “Taking Wing”. So no intentional deception there – but perhaps a failure to look seriously at the available evidence by our authors.

A true transitional form must have structures that are part way between feathers and scales, and forelimbs that are partway between legs and wings. Everything on the archaeopteryx is fully developed. Like the platypus it is an unusual collection of fully developed traits.

Nice straw man argument there! This is not how biologists describe transitional forms.

Incidentally, modern birds have been found in the same and lower levels than archaeopteryx.

Bzzzt! Wrong again. The early birds contemporaneous to Archaeopteryx were not truly “modern”, although you could argue that they were more bird-like than Archaeopteryx. (I wonder if they may be referring to Protoavis?)

Some mammals have teeth and some don’t. Some fish have teeth and some don’t. We don’t see any issue with a fossil bird having teeth. And again, if fossil birds had teeth and today’s don’t, it is a loss, not a gain of genetic information.

Well, no - because some rather cool experimental work has shown that hens still have the genes controlling tooth development, so there has been no ‘loss’ of information. Sorry, guys, if you are claiming to teach science, then it would be a good idea to actually check out the available information rather than making these unsupported statements. In other words, your concluding statements don’t match the evidence & are wrong, wrong, wrong – and betray a wilful misunderstanding of evolution, as well:

Artists have creatively imagined what a true transitional form between reptiles and birds may have looked like. Such “creatures”, if they ever existed, wouldn’t be able to either fly or climb or run properly to escape predators or catch prey. Natural selection would have removed them. (Natural selection is on our side.) The unwelcome position of the evolutionist is that every step, and every small change, must be useful to the carrier to avoid being selected against.

Sigh. Spot the straw men? Not to mention the misunderstandings about natural selection & how it operates…

Update: the February 2011 National Geographic stated that the archaeopteryx, whose well developed feathers causes [sic] a problem for dino to bird dating, was probably such a good flier, that it could probably take off from the ground [emphasis in the original]. Well done National Geographic! We hope that the corrections flow down to the textbooks, but this may be hoping too much.

What is really hoping too much, I suspect, is that the authors of this school’s site take the time to look carefully at the available evidence & see where that leads them. (National Geographic’s represenation of a land-based takeoff is right in line with what most palaeontologists have said for years.) In this particular case they could make a start with reading Shipman’s book for an introduction to the science that’s written for the lay reader.

Pat Shipman (1988) Taking wing: Archaeopteryx and the evolution of bird flight. Touchstone. ISBN 0-684-81131-6

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