SciBlogs

symphony of science: the world of the dinosaurs Alison Campbell May 13

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 I occasionally (very occasionally, right now, with my workload the way it is) watch the Symphony of Science series on youtube. Today I took a few minutes & watched "The world of the dinosaurs", which is quite good** in a techno- sort of way.

Why am I mentioning this? Because when I was taking part in Primary Science Week, dinosaurs did get a mention. Most children seem fascinated by dinos (partly, I suspect, because they are big, dangerous, & safely extinct, as Stephen Jay Gould once remarked), and that fascination can lead them into all sorts of science-based questions. Perhaps we should make more use of dinosaurs, in primary education. (Plenty of opportunities there for building dino-science into literacy and numeracy work, after all!)

** although the pedant in me insists on noting that pterosaurs, pliosaurs, & their ilk were most definitely not dinosaurs!

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musings on national primary science week Alison Campbell May 08

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As I mentioned in my last post, this week is National Primary Science Week, intended to provide science-focused professional development for primary school teachers and competitions, activities,and resources to support science teaching. I’d been asked if I’d contribute to the local program in Hamilton, & so today I trotted off to Berkeley Intermediate Normal School with a small selection of skull casts clutched in my arms (I discovered a few years back that this habit had earned me the moniker of "the Skull Lady"!). I’d been asked to run an activity on teaching about evolution: the best way to do this, to me, has always been to model it, & the hominin skulls where there to give us a bunch of talking points.

So there I was, with a room full of eager youngsters, their teachers, the bones and a whiteboard. The time flew by – in fact, we went well over time, talking for nearly 2 hours rather than the scheduled one. The students were great – attentive, courteous, curious, enthusiastic, & deep-thinking, and the questions they asked were at times really challenging. We talked about common descent; relatedness; common ancestry (& why the common ancestor of humans & chimps would look different from both); why infant chimps and humans look more similar than the adults; natural selection; mutations; human migration patterns; why carnivores have bigger brains than herbivores; how scientists actually ‘do’ science and why their ideas on an issue might change; what the two words in a binomial name tell us; radiometric dating; how to tell the age of an individual at death; how to tell the gender of a set of human remains; why Neanderthals became extinct… and along the way we somehow got onto anencephaly, & ethics! 

I think we all enjoyed it, and everyone gained some new knowledge. Personally I found those two hours great fun, but also challenging and, well, quite tiring! I don’t know that I could manage to be a primary school teacher, actually :-)

One of the key things I got out of today, actually, was a reminder of the huge enthusiasm that young students have for science. The desire for knowledge, and the thinking skills, that I saw today were truly inspiring. But that keen scientific curiosity is also something that we need to feed, and support, and encourage. Primary school teachers, in particular, need all the help they can get in this area. So next year, if you’re asked to contribute to National Primary Science Week – say ‘yes"! In fact, why wait until then? I rather think your local primary school might be glad to hear from you now :-)

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the ero on primary school science: ’should do better’ Alison Campbell May 02

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The Education Review Office’s report on primary school science is all over the news today: here at Yahoo, for example. You’ll find the original paper, Science in the New Zealand Curriculum: Years 5 to 8, on the ERO website. It does not fill me with joy and the following quotes from the report’s Overview should show why:

Effective practice in science teaching and learning in Years 5 to 8 was evident in less than a third of the 100 schools [surveyed for the report]. The wide variability of practices between highly effective and ineffective practices was found across all school types.

And

Few principals and teachers demonstrated an understanding of how they could integrate the National Standards in reading, writing and mathematics into their science programmes. In the less effective schools principals saw science learning as a low priority. They struggled to maintain a balance between effective literacy and numeracy teaching, and providing sufficient time for teaching other curriculum areas, but particularly science.

And

Knowledge-based programmes were evident rather than interactive thinking, talking, and experimenting approaches… Student involvement in experimental work was variable.

So – I was saddened by the report, & I wasn’t exactly surprised either. I’ve written previously (here, for example) about the problems and challenges faced by primary school teachers wanting to enhance their students’ understanding of & engagement with science. Back in 2010, Bull et al presented data showing that the average NZ primary school student spends 45 hours a year studying science (it was 66 hours in 2002), with only 6 other countries of those surveyed spending less time on the subject.  The other worrying point was that the number of students reporting that they never did experiments increased between 1999 & 2007. At the time I commented that it could simply have been that the students didn’t always recognise when they were involved in science activities, but also that at least some primary teachers might lack confidence in teaching science & so omitted it from any integrated lessons. And indeed, the 2010 ERO report cited by Bull & her colleagues found that

most primary teachers did not have a science background and that low levels of science knowledge and science teaching expertise contributed to the variation in quality of science teaching across schools… [and] that many teachers had not learned about science in their pre-service teacher training.

Nor am I surprised that schools & teachers struggle to balance the literacy & numeracy requirements of National Standards with encouraging students to a deeper understanding of science. After all, it’s not that long ago since schools lost the services of school science advisers, who’d been tasked with supporting science education and teachers’ professional development in this area. That loss makes it rather ironic that this latest ERO report recommends that the Ministry should look at ways to provide such support and ongoing professional development in areas including:

  • integrating literacy and numeracy into science teaching and learning
  • considering the place of National Standards for achievement in reading, writing and mathematics across all learning areas, including science
  • developing an approach to inquiry based learning that maintains the integrity of different learning areas, including science.

A ‘back to the future’ prescription, in a way. And, if we accept that science and technology and engineering and mathematics are crucial to our future, it’s a prescription that needs to be met. Students who have positive, engaging experiences of those subjects at primary school might just be more likely to want to continue their engagement at higher levels. Including going on to study at university level. In light of today’s statement by the Tertiary Education Minister, Stephen Joyce, that the Government intends to “rebalance tertiary education toward science, technology, engineering and maths”, then all science educators (primary through tertiary) need to look at how to support teachers and students in developing that engagement.

And in that same light: next week is NZASE National Primary Science Week, set up to offer both engaging activities for primary students and free professional development opportunities for their teachers. There’s a lot going on in the regions, and they’re a brilliant opportunity for scientists in the universities, research institutions, and industries to help deliver the support that our colleagues in the primary schools desperately need. So, a question for my colleagues: what can you do to support this event, if not this year, then next? It could just make a difference, in your own classroom or workplace, in the future!

A.Bull, J.Gilbert, H.Barwick, R.Hipkins & R.Baker (2010) Inspired by science: a paper commissioned by the Royal Society and the Prime Minister’s Chief Science Advisor New Zealand Council for Educational Research (NZCER), August 2010

Education Review Office (2012) Science in the New Zealand Curriculum: Years 5 to 8.

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literate primates? Alison Campbell Apr 15

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ResearchBlogging.org

A while back now, I wrote a brief piece commenting on the ability of at least some chimpanzees to recognise numbers. So it didn’t come as a huge surprise to hear that members of a baboon troop could distinguish between ‘real’ words and random strings of letters. Yes, really.

A group of psychologists led by Jonathan Grainger (Grainger, Dufaur, Montant, ZIegler & Fagot, 2012) have just published a paper in Science entitled “Orthographic Processing in Baboons (Papio papio)”, where ‘orthography’ is a standardised system for using a particular writing system (script) to write a particular language. The team noted that most research on visual word recognition hasn’t treated words as ‘visual objects’, instead dealing with the relationship between information at the letter level and ‘higher-level linguistic properties including semantics & syntax. But it seems that the ability to recognise words as entities resides in a part of the brain that’s also involved in recognition of objects & faces, and primates are pretty good at faces, so Grainger & his colleagues decided to investigate whether baboons could extend their facial recognition skills to identifying words.

More specifically:

The computation of letter identities and their relative positions is referred to as orthographic processing, and there is a large consensus today that such processing represents the first “language-specific” stage of the reading process that follows the operations involved in the control of eye movements (bringing words into the focus of central vision) and early visual processing (enabling visual feature extraction). In the present study, we examined whether the ability to efficiently process orthographic information can operate in the absence of prior linguistic knowledge.

Hence the decision to work with a non-human primate species: baboons don’t use any phonological equivalents of English words (or, most likely, words in any other human language), & so can’t be said to have any prior knowledge of a human linguistic system .

So, what did the researchers do? They worked with a captive social group of baboons that were living in a large enclosure with various climbing structures & sleeping areas, & set things up so that the animals also had free access to a set of test computers that used touch-screen technology & provided operant conditioning: the animals would get a food reward for correctly recognising an English word (as opposed to a string of random letters). The ‘free access’ thing is important – the baboons could get involved, or not, as they chose.

Using that operant conditioning, the baboons learned

to recognize four-letter English words and distinguish them from strings of letters that are not English words.

Each time a letter string (word or non-word) showed on the screen before it, a baboon could touch either a blue cross (for a random set of letters such as DRAN, LONS, TELK, or VIRT) or a green oval (for a four-letter word such as such as DONE, LAND, THEM, or VAST). A correct response was rewarded with a blank computer screen & some food (dry wheat), while an incorrect choice got a green screen for 3 seconds. They began with a single genuine word option & worked up from there (my emphasis):

Words and nonwords were presented randomly in blocks of 100 trials. The 100-trial sessions were composed of 25 presentations of a novel word to learn, 25 presentations of words randomly selected from already learned words, and 50 nonword trials. Each new word was added to the ever-increasing pool of already learned words, once responses to that word exceeded 80% correct within the preceding session. Thus, in terms of explicit information available to the baboons, a word was defined as a string of letters that was repeatedly presented, whereas a nonword was rarely repeated.

During the course of the experiment, individual animals learned to recognise a surprising number of 4-letter English words (from 81 for ‘VIO’ to 308 for ‘DAN’) – correctly distinguishing the words they recognised from a total of 7832 ‘non-word’ combinations.

Obviously the baboons were simply making random choices at the start of the experiment, and in fact they did this in quite a biased way, with each individual tending to go repeatedly for either the green or the blue button. But – after 2000 trials, they became a lot more accurate, correctly identifying words around 75% of the time. And they were doing this on the basis of different frequencies of letter combinations, rather than ‘just’ memorising the real words (although that would be a rather amazing feat in itself). What’s more,

words that were seen for the first time triggered significantly fewer “nonword” responses than did the nonword stimuli. This implies that the baboons had extracted knowledge about what statistical properties characterize words and nonwords and used this information to make their word versus nonword decision without having seen the specific examples before.

And:

The more similar a nonword was to a known word, the more false positive responses it produced.

The researchers noted that this mirrors responses in skilled human readers in the same situation – a rather unexpected outcome.

So, are we looking at some feature(s) of the way the primate brain is wired, that could be regarded as exaptations when it comes to processing visual symbols? Grainger & his colleagues certainly think so:

The primate brain might therefore be better prepared than previously thought to process printed words, hence facilitating the initial steps toward mastering one of the most complex of human skills: reading.

Grainger J, Dufau S, Montant M, Ziegler JC, & Fagot J (2012). Orthographic processing in baboons (Papio papio). Science (New York, N.Y.), 336 (6078), 245-8 PMID: 22499949

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scientists *do* have a sense of humour :-) Alison Campbell Apr 13

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Scientists, like everyone else, have a sense of humour. (It’s just that sometimes their ‘in-jokes’ may come across as somewhat incomprehensible.) And taxonomy seems to offer fertile ground to indulge that wit. What else can you think, when there’s a tiny tiny snail with the genus name Ittibittium; a fly called Pieza kake (say it out loud); and a trilobite with the binomial name Han solo (yes, seriously!). And yes, there’s more – you’ll find a more extensive list here (thanks to Mark Willoughby for sending me the link). In fact, such punny names (sorry, couldn’t resist it!) turn out to be surprisingly common.

It’s not just the biologists; chemists seem to have enjoyed coming up with funny names for new chemical compounds. Moronic acid, anyone? You’ll find a lengthy list at Molecules with Silly or Unusual Names – but you may wish to exercise a little discretion as to whether you wish to call some of the names out loud :-)

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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.


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cancer – an example of evolution at the cellular level Alison Campbell Apr 10

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It’s more than 3 years now since a very close friend died of cancer. At the time, I wrote briefly of how cancer cell lines can evolve resistance to chemotherapy. Now Orac has written a much longer essay discussing the same thing. It’s well worth reading & would probably make an excellent resource for working with senior school biology students.

Orac ends his essay with the following quote, an answer to those who ask why we have yet to cure cancer (even when using personalised therapies that in some cases target the genes themselves):

The reason we haven’t cured cancer yet is because we haven’t figured out how to overcome the power of evolution. Right now, cancer seems almost always to find a way. Until we figure out a way how to block all the ways it can find, personalised therapy will be effective in only a small proportion of cases.

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in the lecture theatre – but definitely not giving a lecture! Alison Campbell Apr 02

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This is a post I first wrote for Talking Teaching – but hey! it’s about teaching science!

Today’s class was a real experiment for me, & although I try lots of different things in my classes, it was also a step outside my normal comfort zone. (But hey! life would be a bit boring if we always stayed safely inside that zone!) Why? Because I put into practice an idea I stole from my friend & colleague Kevin Gould (who also very kindly let me use the resources he’d developed): today was “design-a-plant” day, & probably to anyone looking into the lecture theatre during the first 30 minutes or so it would have looked as if chaos definitely ruled.

Last Friday I gave everyone an information sheet: descriptions of the features of leaf, stem & root that you might see in plants adapted to different environments. Today I trotted off to the lecture room with a box full of overhead transparency sheets, overhead pens, & printed scenarios (descriptions of a particular environment). The lecture theatre was already full – everyone had come ahead of time! This definitely wasn’t usual (it’s not that they normally trickle in late, but we’re talking seriouslyearly); obviously they were expecting something special. Gulp.

So I put up these slides:

then once they’d sorted out their groups I dished out pens, transparencies, scenario sheets (& copies of the info sheet for those who’d forgotten them), & away we went on a mutual journey of discovery. After all, this wasn’t myidea & I had no idea how it would really work out.

Well! The class erupted into happy, productive noise. I know it was productive because while they talked, argued, explained & persuaded, I circulated, listened in, & answered the occasional question. Those with computers had them open – looking up information related to their scenario. (Next time someone asks a question that I can’t answer on the spot, I’m jolly well going to get someone else to google it for me!) They drew, & altered their drawings, & drew some more. The original 20 minutes stretched towards 30, & still they were focused on what they were doing. I was almost sorry to interrupt :-)

Then, I called for volunteers. A hand went up almost immediately, & its owner came down to the overhead projector, not looking too nervous. She picked up the microphone, described her group’s scenario, & showed – & explained – their response. The next speakers followed just as quickly, and each speaker received a round of applause as they finished.

But the proof’s in the pudding – just what sort of plant had they designed? Well, they didn’t necessarily look like plants that my botanical colleagues could have put a name to, but nonetheless, the explanations each group gave for their particular design were sound, & science-based. They’d obviously taken on board not only the info on that fact sheet, but also the material we’d been looking at in lectures & that they’d found on line. And they’d had fun doing it. (I particularly liked the Nepalese Death Vine – the eerie noise of the wind passing through its herbivore-deterring spines apparently puts the locals off harvesting it, lol – and the Serengeti “cactus” that traps water in basin-like leaves, but when there’s a fire the plant’s transpirative water loss is such that its tissues become flaccid and it wilts, spilling that water onto the ground where the dampness keeps the worst of the fire at bay.) Plus – so far, the feedback for this exercise on our Moodle page is all positive: students felt it definitely helped their learning about plants.

Thanks, Kevin – your design-a-plant lesson got an A+ from all of us today!

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a bag moth in residence Alison Campbell Apr 01

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When I took the cover off the barbecue the other day, a tiny insect caught my eye. It was moving in short, fluttering hops so was fairly easy to catch, and once I had it in a jar I could have a better look. It was less than a centimetre long, dark blue with lovely contrasting golden spots on all four of its short wings. The number of wings told me it wasn’t a fly (despite my husband’s protestations to the contrary), as did its long antennae, which were not quite half the length of its body. And I knew ‘it’ was actually ’she’, because there on the end of her fat little abdomen were two palest gold puffs – her scent glands.

We showed her to friends over dinner (barbecued lamb that had marinated for the day in a delightful mix of soy sauce, garlic, rosemary, lemon zest & lemon juice, with various other dishes on the side), but no-one knew what our little moth might be. And lacking a decent close-up lens on the camera, I couldn’t mount a photo here for other, wiser eyes to identify.

But tonight I’ve just had an e-mail from our dinner guests, who identified her in a book they were browsing through in a second-hand bookstore in Thames. She’s a female bag moth, Cebysa leucotelis, shown here in a photo from the Landcare Research website:

Australian bag moth

This is a strongly dimorphic species, as the male – who is capable of sustained flight, unlike his partner – looks quite different, a dull brown with pale yellow spots on his hind wings & bars of the same colour along the leading edge of each forewing.

The husband was suspicious, lest they be of the same ilk as the pantry moths currently littering the traps in my store cupboard. But no, bag moths apparently eat lichen & algae on the walls of buildings. So our enchanting little house guests can stay, without fear of further disturbance (at least until the next barbecue!).

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’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.

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