SciBlogs

Archive October 2010

“killer neandertals” – does this one really stack up? Alison Campbell Oct 31

15 Comments

I spent yesterday up in Auckland, running a schol bio preparation day. (And thanks to Mike, Cindy, BEANZ & the Auckland Science Teachers Association) for setting it up.) I do enjoy these sessions (& hopefully the students do too!) as I like the interactions with students & they always ask nice, challenging questions.

Anyway, after we’d finished the main proceedings of the day, someone came up & asked if I’d heard of the ‘killer Neandertal’ hypothesis, & what did I think of it? Was it a good explanation for the evolution of modern humans? The quick answer was, no I hadn’t, so couldn’t really comment – but I’d go & have a look :)

I quickly found a website promoting a book by Danny Vendramini. Called Them and Us: how Neanderthal predation created modern humans, the book supposedly provides ”new archaeological and genetic evidence to show [Neandertals] weren’t docile omnivores, but savage, cannibalistic carnivores…” – the ‘Neanderthal Predation theory’. (I noticed that the author uses the spelling ‘Neanderthal’ throughout – a bit surprising as the norm these days is to use ‘Neandertal’, after the correct German spelling for the river valley where the type specimen was found.) Given the lack of any real evidence, and of support for this from the wider scientific community, this position would be better described as an hypothesis…

The website goes on to claim that that

Eurasian Neanderthals hunted, killed and cannibalised early humans for 50,000 years in an area of the Middle East known as the Mediterranean Levant. Because the two species were sexually compatible, Eurasian Neanderthals also abducted and raped human females…. this prolonged period of cannibalistic and sexual predation began about 100,000 years ago and that by 50,000 years ago, the human population in the Levant was reduced to as few as 50 individuals.

The death toll from Neanderthal predation generated the selection pressure that transformed the tiny survivor population of early humans into modern humans. This Levantine group became the founding population of all humans living today.

 

These claims are accompanied by illustrations that make Neandertals appear more akin to gorillas than to modern humans, which is ‘interesting to say the least, given the recent information on genetic similarities between sapiensneandertalensis.  We’re told that the Neandertal Predation ‘theory’ “argues that, like modern nocturnal predators, Neanderthals had slit-shaped pupils to protect them from snow blindness” (thus conflating two ideas - not all nocturnal predators live in snow-covered lands - on the basis of zero evidence, since eyeballs don’t fossilise). And there’s also the statement that Neandertals “had thick body fur and flat primate faces to protect them against the lethal cold.”

Now, that last one is just ridiculous. As far as I know there have been no published findings of Neandertal fossils accompanied by evidence of thick body fur. On the other hand, there is tantalising evidence that they may have had the technology to make sewn garments, thus reducing any selection pressure favouring hirsuteness. In addition, Europe was definitely not in a state of constant glaciation during the few hundred thousand years that Neandertals lived there. During interglacial periods temperatures were fairly similar to what they are today – hardly conditions where a thick furry pelt would be selected for (let alone those slit-shaped pupils…).

As for the ‘flat primate faces’ – if you have a look at a gorilla skull you’ll see that the nasal opening is flush with the surface of the facial bones: gorillas do indeed have flat faces & no protruding nose. But a Neandertal skull, like that of a modern human, does have projecting nasal bones & so, by extension, a nose that juts out from the face. In fact, the whole central region of a Neandertal face projects further forward than ours, so it’s hard to see where Vendramini gets the idea of a ‘flat’ face from. He does provide an image of an Neandertal skull, superimposed onto a chimpanzee profile, & claims that the ‘perfect’ fit is evidence that neandertalensis “more closely resembled non-human primates than a modern humans”. What’s missing is any recognition that the skull is not in its ‘life’ position but presented at an angle that conveniently fits the point of view being espoused. If Neandertals really did hold their heads at this angle their posture would be distinctly odd, to say the least. Similar techniques were used by some illustrators in the 1800s to support the idea that African negroes were closer to the apes than to Europeans.

And the claims of rape and cannibalism are fairly extraordinary. As the late Carl Sagan said, extraordinary claims require extraordinary proof. So let’s go back to some of those statements. How about the supposedly much-diminished group of Levantine humans becoming “the founding population of all humans living today”? How, exactly, does this fit with the fact that the sapiens populations of Africa were not exposed to supposed Neandertal predation? Or with the colonisation of Australia by Homo sapiens around 60-70,000 years ago?

Or the idea of frequent interspecies rape, of sapiens by neandertalensis? By the way, if all this – the brutish images & tales of rape – isn’t intended to demonise Neandertals, then I’m not sure what would. Frankly it smacks of the way this species was portrayed in the years immediately following its discovery, before palaeoanthropologists began to expose the details of its life – for example, a reconstruction by Frantisek Kupka, based on work by Marcellin Boule. Something of a dehumanising stereotype, in other words.

By the way, there’s an interesting paper by Julia Drell (2000: Neandertals: a history of interpretation) that looks at how portrayals of Neandertal have changed over time, as more evidence has become available – and also as societal attitudes have changed. (NB this may well not be open-access.) Drell also notes that suggestions of cannibalism by Neandertals aren’t new, first appearing in the 1860s. She cites an earlier author as saying that “there is no more universally common way of distancing oneself from other people than to call them cannibals.”

In fact, there’s not a lot of evidence of cannibalism in Neandertals -  the remains of about 15 individuals that may have been eaten by their conspecifics. And that over the total span of their existence. (I do wonder why they’d turn to cannibalism anyway, given that they were extremely successful hunters of large game going by the butchered remains associated with neandertalensis living sites.) There is no published evidence that supports the contention that Neandertals ever ate non-Neandertal hominins, let alone on the scale that Vendramini suggests. On the other hand, there is evidence of Neolithic sapiens eating each other.

Nor is there evidence of frequent interspecies rape in the gene pool of modern humans. Earlier this year Green et al announced the sequencing of the Neandertal genome, and the results of a comparison of this and the sapiens genome. Their data did suggest a small degree of interspecific hankypanky might have been going on, but not in large quantity. (The data did not support the idea that all modern humans are descended from a remnant human population in the Levant, as Them and Us would have it; Neandertal genes are notably absent from African populations. Nor does it support the idea of Neandertal predation, despite claims to the contrary on the book’s website.)

The Them and Us website also provides a link to a paper, Neanderthal predation and the bottleneck speciation of modern humans, for the ‘academically minded’. Strangely for an academic paper, the pdf contains no publication details (journal name, volume, & so on) & a Google Scholar search doesn’t throw up any published papers with that name. So it’s a fair bet that this has not been subject to the normal pre-publication process of peer review – something I would expect for an hypothesis that’s supposed to turn our understanding of human evolution on its head…

J.R.R.Drell (2000) Neanderthals: a histroy of interpretation. Oxford Journal of Archaeology 19(1): 1-24

yes, we have some bananas Alison Campbell Oct 29

1 Comment

Prominent creationist Ray Comfort once (in)famously commented that the ‘design elements’ that make up a banana, including its so-convenient shape, are evidence for the existence of a Designer. A comment that has been pretty resoundingly debunked – unsurprisingly, since the banana-as-we-know-it is due in large part to the hand of man, selecting for those features of bananas that make them desirable as a food – lack of seeds (wild-type, uncultivated bananas have almost more seeds than flesh) & that wonderfully unzippable peel. Something that last year’s Schol Bio examination asked students to think about.  

Inside a wild-type banana

Image: inside a wild-type banana (from Wikipedia)

Bananas belong to the genus Musa. If you think back to the last banana you ate, you’ll rememember that it’s seedless, unlike the ‘wild’ banana shown above. All commercially-grown banana plants are produced asexually, from suckers or sprouts. The varieties we import also tend to be rather large, but the fruit can be much smaller (apparently the name ‘banana’ derives from an Arabic word for finger, banan). They’re imported as unripe fruit, & ripened before sale by being exposed to ethylene. Ripe fruit (not just bananas) release this gas, but for commercial ripening the fruit are placed in a room that’s then flooded with it. 

Incidentally that lack of any sort of sex life places banana crops at some risk: because they’re clonal, if a pathogen comes along to which they have no resistance, much of the crop may fail. For example, the ‘Black Sigatoka fungus’ can lower production by up to 50% in infected crops. This problem is magnified by the loss of genetic diversity in wild bananas as rainforests are felled. Another pathogen, bacterial banana Xanthomonas wilt (BXW) disease, poses a significant threat in East Africa. While we may view the loss of bananas as something of a misfortune, for others it would be much worse: after rice, maize & wheat, bananas are the world’s 4th most important food crop.

Now, back to the question. The examiner tells us that “Many different species of banana exist today, all of which are descended from one or other of the ‘wild’ Asian species: Musa acuminata (AA:2n = 22) and Musa balbisiana (BB: 2n = 22). Students needed to pay careful attention to the AA & BB. They represent the genome – the full chromosome set – rather than alleles at a particular locus. This is important, because the question goes on to give you information about the genomes of several of the major cultivars in modern bananas:

Species Genome

 

Cultivars

 

AA

 

Sucrier

 

Jari Buaya

 

AAA

 

Gros Michel

 

Grande Naine

 

Cavendish

 

BB

 

Abuhon

 

Chuoi Hot Qua Lep

 

AB

 

Njalipoovan

 

ABB

 

Awak

 

Pelipita

 

AABB

 

Kluai Ngoen

 

So, the examiner asked scholarship candidates to ”[d]iscuss the sequence of events and processes that have resulted in the three different species of banana with the followign genomes, arising from the original ‘wild’ species of banana: AAA, AB, and ABB,” and advised using annotated flow diagrams in doing this. The discussion also needed to include ”the genetic processes that could have occurred to produce the different cultivars of Gros Michel, Grande Naine and Cavendish within the one species of the AAA genome.” (The question went on to ask candidates to design an experiment to investigate the action of ethylene on ripening rate in bananas, but I think we have enough to look at without going into that right now!)

O-kay. I am not one of those clever people who can do all sorts of flowcharts on their webpages, but if I was, I’d be drawing a flow diagram or two showing things like polyploidy & hybridisation. This is because that first AAA genome must be the result of a cross between 2 M.acuminata individuals where one produced normal (i.e. n = 11) haploid gametes, A, while the other produced gametes (at least some!) which were diploid (AA) due to complete non-disjunction in meiosis. The 3n (AAA) individuals thus produced are autopolyploids (both parents from the same species. Because as triploid organisms you’d predict they’d have difficulty producing gametes of their own, these AAA plants are sterile & can reproduce only asexually.

The second (AB) species is the result of a hybridisation event involving one M.acuminata parent and one from M.balbisiana, both producing haploid gametes. And tthe third, ABB, species is another polyploid organism. This time it’s an allopolyploid (2 different parents) with the M.acuminata parent contributing a haploid gamete (A: n = 11) while the M.balbisiana parent must have produced some BB (2n = 22) gametes, again through complete non-disjunction during meiosis. (You could probably get away with not drawing flow diagrams, but in that case you’d need to give a comprehensive & logical description of what was happening.)

What about those different cultivars with the one genotype (AAA)? Two possibilities here. One is mutations after the AAA triploid was formed. In some cases mutations – in different plants – could result in different phenotypes. And if those phenotypes were viewed as ‘desirable’ by farmers, they’d be propagated by cuttings, ending up as the different cultivars.

The other possibility is that the original parent plants (those AA individuals) had differences in their genotypes. This is really only to be expected, given the fact that independent assortment, crossing-over & recombination routinely shuffle alleles between homologous chromosomes, and homologues assort independently when gametes are formed. Again, when the AAA polyploids were produced (I think it’s safe to assume this could happen more than once) then they’d receive these variations from their parents. And again, any ‘desirable’ phenotypes would be selected for.

There! Isn’t that a rather more satisfying explanation than Mr Comfort’s?

sounds of biology Alison Campbell Oct 27

No Comments

I rather like the way music & science seem to come together quite often these days :)

That thought bubbled to the top after I ran a pre-exam tutorial for my first-year bio students. After a couple of hours we’d all pretty much run out of oomph, so I thought that a bit of light relief might be a fun way to unwind & finish off. So I shared the glucose song – very apt, given that we’d just been talking about how insulin controls glucose uptake at the cellular level. (Plus it’s such a catchy song – I always have to resist the urge to dance along!)

 

 

Of course, if you go looking, there’s more. There’s the genes rap:

 

 

There’s this one on DNA replication & protein synthesis (superficial overview but a catchy beat!):

 

 

And to finish off with: many of you will be familiar with the PCR song – I’ve mentioned it before but it’s great fun & worth another look :)

 

 

OK, they may not be everybody’s cup of tea. But my students enjoyed them – & thought them fun aides-memoires (oh, alright, they didn’t actually say that! but the intention was there) for some of the serious concepts that they need to understand and remember.

vaccination in the classroom Alison Campbell Oct 24

2 Comments

Because I used to be a secondary-school teacher (rather more than a few years ago now) & also because I interact a lot with school teachers, I’m following that sector’s current pay negotiations with quite a bit of interest. One of the conditions that the teachers’ unions have placed on the table is the issue of employer-funded influenza vaccinations.

My own employer provides these. And I think they’re great. I’m not going to expose my students to infection, & similarly, I’m much less likely to pick it up from them. (And if I’m sick, no-one else takes my lectures; they’re cancelled. So there’s a strong tendency among staff to come in to class regardless.) Consequently this seems a no-brainer to me. And yet…

… in (I think) the Herald’s letters columns last week, a correspondent complained about this. What health risk, they said, could possibly be posed by teaching in a classroom?

Obviously this person doesn’t follow the news particularly closely. Every time there’s a virulent strain of influenza doing the rounds, news reports tell us how schools are having to deal with large numbers of absent students – and of teachers. There are costs to both.

If kids are home sick then there’s probably a parent home looking after them (unless they’re over 14, & frankly with a child with anything more than sniffles & a bit of a headache I’d be worried about leaving them alone, even then), which means taking sick leave or – if on a wage – losing pay. Not to mention that the child is missing out on classes – a big thing, if it’s an examination year & you’re sick for more than a day or two.

And if teachers are away, well, what happens to their classes? If the school can find a relieving teacher to stand in for them, that’s good, although the reliever may not actually be trained in the same subjects as the sick individual, so the classes aren’t going to cover the material so well. If there are no relievers available, then the school administrators have to fall back on other teaching staff, who end up taking extra classes in the ‘free’ periods, during which they’d otherwise be doing marking, preparation, report-writing, & so on. And (unless things have changed a lot from when I was a teacher) the person calling in sick is still expected to provide materials/instructions for whoever will be standing in for them.

So providing vaccinations for teaching staff brings with it a lot of benefits. Teachers are less likely to pick up the virus from some among those 30 or so students in their classroom, who’ve come to school when they should be at home in bed. The schools won’t have to spend so much on calling in relieving teachers, or ask other staff to pick up the load. Students’ learning is less likely to be disrupted through having their regular teachers off sick. And those students are also less likely to be exposed to the current flu strain(s) by a teacher who’s come in to school to teach that day even though they’re feeling well under par.

And because those benefits are so broad, having employer-funded vaccinations for teachers seems – to me – to be a very reasonable requenst to put on the table.

(Those who are interested in this issue might also like to read Mark Crislip’s latest post on Science-Based Medicine, on whether influenza vaccination should be mandatory for health-care workers. Personally this one seems even more of a no-brainer, considering the potential for said health-care workers to pass on the virus to patients whose health is already compromised.)

another resource about critical thinking Alison Campbell Oct 19

No Comments

I had a great time down in Hawkes Bay over the weekend, running a Schol Bio workshop for teachers & students from the local schools. I really enjoy these sessions as I get to catch up with the teachers & to work with some very talented young people, who can be guaranteed to ask me curly questions & keep me on my toes. All good stuff  :) (And OK, I enjoy the chance to cruise a couple of vineyards as well! Plus it’s always nice to get back to your roots – I was born in Napier & lived first in Tutira, then Wairoa, & finally Hastings before upping sticks & moving to the Manawatu.)

However, the downside of all this is that the Other Stuff simply doesn’t go away while I’m otherwise engaged :( So right now I’m wading through marking of essays & tests. (The ‘flounder’ effect, anyone?) Which kind of makes it hard to find time to write anything substantial for you, my readers.

And because of this – a big ‘thank you!’ to Mike Stone, for pointing me at The critical thinking toolkit on the University of British Columbia’s website. I can see that I will have to include some of this in the workshop I’m running up in Auckland in a couple of weeks.

Make sure that you scroll down to the great video at the end!

inspired by science Alison Campbell Oct 15

7 Comments

A couple of days ago I was sent a copy of Inspired by Science (Bull et al. 2010) – a paper written ‘to encourage debate on how better to engage students with science’ which focuses particularly on what’s going on in our schools. It also asks ‘whether there is an increasing mismatch between science education of today and the demands of the 21st century.’ Those of you who are regular readers will know that this is a particular interest of mine (& of several of my blogging buddies over at Sciblogs), & so of course I was very keen to read the paper :)

Way back when I was a secondary science teacher (& we really are talking last century here!) I remember thinking that some of what we were teaching wasn’t all that useful to students in their everyday lives (just how relevant was an understanding of how urea fertiliser is manufactured, for example). If students don’t see something as relevant they’re likely to switch off, & in fact Bull et al. (2010) comment that ‘many students do not achieve sufficient understanding of [science] to be able to contribute to scientific debates.’ So if ‘society’s educational purposes’ (ibid.) include a population that sees science as relevant & that’s able (& willing) to take part in such debates, then maybe we need to look at how the subject’s taught. Otherwise the trend towards disengagement from science that Hipkins & Bolstad identified in their 2008 paper, Seeing yourself in science, may become a landslide.
 
And indeed, that’s what informed the development of the new curriculum now being implemented in our schools. This may well be seen as a problem by university lecturers in the various science disciplines, whose views of what should be taught in school science curricula differs from the one set out in this paper, and which I hold as well. In other words, different interest groups can have quite different, & deeply held, beliefs about what schools should be doing. And because up until fairly recently students in year 13 (7th form) classes tended to be the ones going on to uni, content & assessment were pretty much driven by the needs & demands of the universities, delivering chunks of knowledge & with not all that much attention to engaging them with the nature of science (NOS) itself. Even when the 1993 curriculum introduced NOS as a ‘parallel strand’ alongside general science & the indivdual subjects of biology, physics, chemistry, that strand tended to be ‘the pages we just skip over’ rather than an integral part of the curriculum. The current curriculum set out to change this, but nonetheless Bull et al. are able to identify several factors working against such change. And they comment that ‘understanding what good science education looks like – that is, science education that is educative, that represents science accurately, and that is engaging for students – is very challenging, and that, despite much effort, it continues to be very challenging.’
 
Of course, this does raise the question: how do we know when students are engaged? What does this thing ‘engagement’ look like? Bull et al. offer several possibilities here: continuing with study; demonstrating true intellectual curiosity about science & what it can & can’t do; showing interest in things like technologies, environmental issues, science media; aspiring to a scientific career; evincing a belief ‘in the value of science to the individual & to society’. You may be able to think of others. And this all feeds into how we assess the quality & success of the science education offered in New Zealand classrooms – it’s one thing to have students ‘doing’ science, but just how worthwhile is that if they don’t actually want to be there?
 
While I work mainly with senior biology students & their teachers, I’m aware that many students make up their minds about science as a subject for further study rather earlier than that, which means that their science experiences at primary & intermediate school are crucial to that decision. Surveys like TIMSS* and NEMP** show that primary school students enjoy science, report positive experiences of it, and would like to study more science :) Alas! this enjoyment and positive attitude declines as students move through to their secondary school years, & most students have pretty much decided about things like a having a science-related career well before they hit senior secondary school. Which suggests that a lot of our effort in engaging and supporting students in science should be focused on those primary & intermediate years – but not to the detriment of science teaching in secondary schools!
 
However, recent data from TIMSS (cited by Bull et al., 2010) indicate that primary students in this country spend on average 45 hours/year on science – well down on 66 hours in 2002 – and that only 6 of the other countries taking part the survey reported spending less time than that on studying science. Along with this, the number of students reporting that they never did experiments (something kids love!) has increased declined  over the period 1999-2007. Now, because a lot of classroom teaching is cross-curricular, the children surveyed may simply not have recognised when they were doing science activities. But conversely, primary teachers may lack confidence in teaching science & so don’t include it in any integrated topics they may be teaching. This isn’t surprising as according to a 2010 Education Review Office report (also 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.’
 
So, if we’re going to turn this around, to improve the quality of science education in students’ early years at school, and enhance and maintain their engagement with the subject (however this manifests), then surely we need to make sure that primary teachers a) receive greater training in science than is currently the case & b) are better supported to deliver science experiences to their students. This doesn’t mean simply having a specialist science teacher in each primary school as this by itself may not be sufficient to change attitudes — it means all teachers in primary schools having regular access to relevant professional development and to specialist advice from trained science advisors. Both are extremely important. However, there are significant funding issues surrounding the provision of professional development, and in addition the introduction of National Standards appears to have focused attention elsewhere, away from the delivery of science. (I know that it should be possible to address the Standards within the context of science — or pretty much any other subject — but the risk is that this won’t be recognised by many teachers without opportunities for further training.)
 
For example, in late 2009 the Minister advised schools that the relevant university advisory groups would not be providing schools with help in any subjects other than reading, writing & mathematics, which may well have a negative effect on how science is taught in primary schools. This is not the first instance where PD has been delayed or removed: the same thing happened in regard to professional development for the Science Exemplar project & development of Building Science Concepts resources, with lack of funding cited in both instances. The related issue of whether/how to get scientists from the various research organisations more deeply involved with schools is no substitute for enhanced training & support for the classroom teachers themselves. So any suggestion of a national program directed at enhancing primary school science programs would be a very welcome one.
 
At the secondary level — I agree wholeheartedly that professional development involving both scientists & teachers is the way to go, with positive spin-offs for both teachers & the scientists involved. In fact, this sort of relationship should be in effect at all levels of schooling, as it would promote a situation where ‘[students] are challenged to develop deep understanding through strategies that emphasise student questioning, exploration, and engaging with significant ideas and practices. There would be much greater interaction between schools and the science community and more emphasis placed on students’ active engagement in their own learning’ (Bull et al., 2020).
 
With two caveats: firstly that it will be essential for those scientists involved in such programs to receive proper recognition for this role from their institutions, in things such as promotion rounds, as this would send a clear signal that these activities are valued. And equally important is the need for discussions around what is ‘core’ to the science curriculum. My experience in biology is that as new techniques or information become available they tend to be ‘front-loaded’ into the curriculum (e.g. by way of things such as the explanatory notes that accompany Achievement Standards) without any real consideration of how to fit everything in or, indeed, what might usefully be omitted in their place. I have argued for some time now that these discussions are essential in all science subject areas but see little real sign of this happening. But that over-full curriculum may give little opportunity for students to spend time discussing what they’ve learned, or take a creative approach to classroom work, especially if they’re working towards a series of assessments over the year. Maybe, with the advent of the new curriculum, there’s the opportunity for changes in teaching & assessment practices – maybe things like the integrated learning programs that some secondary schools have developed? - that will turn us around from the situation described by Bull et al. where ‘[traditional] science education, designed to prepare science-able students for science careers, is in fact turning many students away from science…’
 
And of course, there’s also the need for proper funding of professional development to make all this possible…
 
Unfortunately there’s quite a lot of support for ‘traditional’ science teaching among university academics, & the modes of teaching that are becoming more common in secondary classrooms have yet to make much of an inroad in the tertiary sector. This is a real pity as I believe such changes would go a long way towards enhancing students’ success as they move into their tertiary studies. There’s also a failure by many in the tertiary sector to recognise that university is not the next destination for a sizeable proportion of year 13 students. For example, while collectively our universities do emphasise the importance of the ‘secondary-tertiary interface’, one document on Te Pokai Tara (the NZVCC’s website) states that ‘the appropriate interventions must continue at the secondary level to minimise the extent to which bridging support is necessary at tertiary level.’ On the face of it, this fails to recognise the diversity of learning experiences offered to secondary students and the reasons for that diversity. Such expectations have the potential to constrain schools’ ability to offer innovative combinations of achievement standards that best meet their students’ needs & interests, and run counter to the intention of the New Zealand Curriculum.
 
I’d like to make a call for the development of a much stronger relationship between coordinators of first-year university classes (in particular) and secondary schools as there would be clear benefits for all parties involved: significant opportunities for professional development of both secondary & tertiary teachers; enhanced opportunities for secondary students to learn of new developments & opportunities in science; and improvements in the ability of tertiary teachers to bridge their students into successful university study (highly desirable now that TEC will be linking funding to completion & retention). This is something that I’d be very keen indeed to be involved in developing, & in fact I’m looking forward to speaking about it at an upcoming first-year biology educators’ colloquium, in Dunedin at the end of next month :)
 
* TIMSS = Trends in International Mathematics & Science Study
** National Education Monitoring Project
 

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

R.Hipkins & R.Bolstad (2008) Seeing yourself in science: the importance of the middle school years. NZCER

lady gaga in the lab? Alison Campbell Oct 11

16 Comments

The government’s Tertiary Education Strategy makes it clear that New Zealand needs to continue to develop a well-educated workforce, and that one of the priorities within this is to support high quality research that helps to drive innovation. So it’s fair to say that a fair proportion of that workforce needs to be employed in areas based on science, technology & education. To achieve that, we need to have a steady (& even increasing) throughput of students who successfully study those subjects at tertiary institutions. And to achieve that, we need to get school students thinking that a career in science/technology/engineering is definitely The Way to Go.

And therein lies the rub. Because there are so many other career options available to school students today, & so many other subject options to take at school. So how do we get students thinking about science, technology & engineering as part of their future? Maybe by producing video (or youtube) clips of cool young scientists talking about their jobs & how they got there? At Discovering Biology in a Digital World, Sandra Porter has another suggestion: music videos!

 

 

One of the commenters there suggested that hooking kids into thinking about science in this way is almost dishonest: if they’re not already interested in working in science in the future, then we should just leave them alone & cater just for the already-committed. Me, I’m with one of the others. Often when you see a science lab on TV it’s almost obsessively tidy & full of serious people doing Serious Stuff. A young person keen on science & wondering if they’d like lab work might be put off by that sort of formality. But the scientists shown in this clip are fairly young, obviously having fun & enjoying what they do, & the lab looks like a real working lab. (Although our Health & Safety people would have conniptions about the goings-on!) I’m not suggesting that we ditch the careers talks & go to town with Lady Gaga spoofs – but maybe there’s room for both approaches?

a novel take on a fairy tale Alison Campbell Oct 10

2 Comments

Well, it’s Sunday, & time for something different. Very different…

… a novel take on Little Red Riding Hood - found via Graph Jam. Sort of science-y in a fun sort of way, in its use of graphics & cutaway diagrams. I’m always filled with admiration for the clever folks who have the skills & imagination to do this stuff.

But I still felt a bit sorry for the wolf. (Although the Pratchett version, in Witches Abroad, is an altogether more pathetic figure).

 

stunning biological images Alison Campbell Oct 08

No Comments

.. but perhaps not for the squeamish, not over lunch anyway! Grant & I were e-chatting about some of the great science images we’d seen, & I thought of this one: via PZ comes some stunning imagery of a python digesting a rat. Here’s my favourite from that gallery. (Come to think of it, one of the python actually ingesting the rat would have been rather cool!)

Your turn, Grant :)

a good example of thinking critically Alison Campbell Oct 07

No Comments

One of my regular readers wrote to me today, about an advert that she’d stumbled across recently. I asked if I could reproduce it here (changing some names) as it’s a very good example of someone thinking critically about claims made for a particular product.

‘Jane’ writes:

OK, my skeptic-o-meter is going off big time… have you ever heard of Product X?  It’s a ‘natural’ insect repellent which makes some interesting claims…
 
Product X works in 3 very unique ways:
1.Product X hides the user from the mosquito making it difficult for the insect to find you.
[Me: given that mosquitoes use exhaled CO2 as one way to find their next bite, using body heat as an extra guide, this sounds rather unlikely. It may possibly mask your odour, which is another cue that female mosquitoes use when looking for a blood meal.]
 
2.If the mosquito does actually land and tries to bite, Product X will interfere with the insect’s nervous system making it difficult for them to bite at all.
[Me: that is possible. I've seen claims that the essential plant oils contained in products like this interfere with insect nervous systems by disrupting the action of a neurotransmitter called octopamine. There is certainly evidence from both in vitro in vivo studies that essential oils have an effect on insect nervous systems eg here & here, with suggestions that these oils could be used as both pest repellents & pesticides. But perhaps it's just that ,when they get up close & personal, the mozzies are put off by the smell.
Just as an aside, octopamine's also found in vertebrates but there's been little research into how it operates.This hasn't stopped people promoting its use as a slimming aid... ]
 
3.Elements of Product X also have skin soothing properties to ease the discomfort of previous bites.
Product X is also biodegradable and the packaging is recycled and recyclable, so its good news for the environment too. 
Buy this 2 pack now and enjoy your summer free from bites and itches.
·    gentle formula
·    water resistant
·    6 hours protection
·    contains no DEET or Citronella
·    great for camping, school trips
Pack contains: 2 x 100ml Product X natural repellent

"As a regular worldwide traveller I can recommend Product X in all climates and conditions. It's one of the first things into the suitcase ! Try it yourself and you will be converted." Author Brian Jeffrey 
I like the endorsement from an author, particularly one who has no listings on Amazon…
 
It appears to tell us what’s not in the product, but not what is in it… the website also claims ’Contains NO chemicals yet proven to be as effective as chemical based products such as DEET’ but doesn’t appear to substantiate this claim. 
 
[Me: 'contains no chemicals is a common claim but since everything is made up of 'chemicals' it's an inaccurate one. If the product somehow did manage to contain no chemicals at all then it would also be effect-free. Unless it operates on homeopathic principles... - let's not go there! But from what I can find, it contains volatile plant oils, which are definitely chemicals. 'Natural', perhaps, but definitely not 'chemical-free.] 
 
Lots of online stores selling this product have personal testimonials, mention that in ’trials’ it has outperformed traditional repellants, and one even claims it has been road-tested by military personnel… but all with a  surprising (!) lack of actual evidence, or links to aforementioned trials.
 
Is my skeptic-o-meter functioning correctly??
 [Me: oh yes, very definitely! Having lots of testimonials, but no actual data, should always make you question the claims made for a product.]
 
Regards,
Jane
 

Network-wide options by YD - Freelance Wordpress Developer