Posts Tagged ‘science’
Canto: So I’ve just read a book that details experiments highlighting the effects of, for example, colour, odour, physical comfort and ’embodied metaphors’ on mood, decision-making and creative thinking…
Jacinta: Embodied metaphors?
Canto: I’ll explain later, or not. What I want to do here is lay the groundwork for a future PD talk on how these findings can improve our educational settings and teaching.
Jacinta: So you’re saying our environment can be manipulated, perhaps, to bring out better results in students?
Canto: Yes, think about it. Will sitting in a soft chair help you to think more creatively or efficiently than sitting in a hard chair? Will standing or walking around improve your thinking? Don’t forget Harry Stottle and the Peripatetics. And can these effects be measured? What about the temperature of the room? The view from the window? Inside or outside?
Jacinta: Okay, so can you give me some solid research data on anything that can improve, say, test scores?
Canto: For a start, don’t ask females to indicate that they’re female on the test booklet when they’re sitting a mathematics test. Their results will be impaired. The very act of writing that they’re female apparently brings to mind the idea that girls can’t do maths. The same has been found with African-Americans and maths. This phenomenon is well known in the literature, and has been called stereotype threat.
Jacinta: Okay, but is this really an example of what you were talking about? I thought it was all about the effect of colour, temperature, lighting etc?
Canto: I’m talking about embodied cognition, or physical intelligence, and yes that research is an example – by getting someone to write their gender before sitting a test, it makes them more aware of their gender; their embodiment is brought to mind. But I’m going to give some quite striking examples of the influence of the colour red on test results. A team of American and German researchers conducted a number of experiments, the first involving 71 American undergrads. Each subject was tested individually. They were told they’d be given an anagram test, in which they had to unscramble sets of letters into words. These were of medium difficulty. After a practice run, the students were randomly divided into three groups. All students were given the same anagram tests on paper, with one difference – each participant was given a number, but with one group, the number was coloured red, with another the colour was green, with the third the colour was black. The number on the top of the paper was called to the subjects’ attention at the beginning of the test, with the excuse that this was necessary for processing. The difference in the test results was striking – those who saw a red number at the top of each page performed significantly worse than the green and black groups.
Jacinta: They saw red, and fell apart? But why would they do that? Has this study been replicated? Maybe the group with the red numbers were just bad at anagrams?
Canto: Good questions, and of course it’s the sort of study that could easily be replicated, but the results are in line with similar studies. Unfortunately I could only read a brief abstract of the original study as the detail is behind a paywall, but all these studies have been written about by Thalma Lobel in her book Sensation: the new science of physical intelligence, and, according to her, this particular study took into consideration the abilities of the groups and made sure that this wasn’t the cause of the difference. Also, the same researchers did a follow-up test in Germany, with altered experimental conditions. Instead of using anagrams they used analogy tests, such as:
legs relate to walk like:
1 tongue to mouth
2. eyes to blink
3. comb to hair
4. nose to face
Jacinta: Right, so the correct answer is 2, though it’s not the best analogy.
Canto: Well, eyes to see might be too easy. Anyway, 46 subjects were given 5 minutes to come up with 20 correct analogies. The analogies were presented on paper, each with a cover page. The subjects were divided into 3 groups and the only difference between the groups was the colour of the cover page. The first group had red, the second green, the third, white. This time their exposure to the colours was shorter – only seconds before they were asked to turn the page, and they weren’t exposed to the colour during the test itself, after they’d turned the page. Still the results were much the same as in the first experiment – exposure to the red cover page resulted in poorer scores.
Jacinta: Sooo, red’s a colour to be avoided when doing tests. What about the other colours? Were any of them good for improving test scores?
Canto: No, not in these experiments. And again, Lobel assures us that the study controlled for the variable of differential ability. The researchers conducted other studies on a range of participants – using verbal and non-verbal (e.g. mathematical) tests, and the results were consistent – exposing subjects to the colour red, and making them conscious of that colour, resulted in poorer scores.
Jacinta: And they have no explanation as to why? Presumably it’s some sort of connotative value for red. Red is danger, red is embarrassment…
Canto: Nature red in tooth and claw – but red is also the heart, the rose, the Valentine. Red has all sorts of contradictory connotations.
Jacinta: So isn’t it the way that red is seen in our culture? What about controlling for cultural connotations, however contradictory?
Canto: You mean trying it out in Outer Mongolia, or a remote African village? It’s a good point, but you know red is the colour of blood..
Jacinta: And of my life-producing vagina.
Canto: Yeah but look at the wariness with which women are treated for having one of those. Anyway I’m not sure they’ve done the study in those places, but they’ve varied the settings – labs, classrooms, outdoors – and the age-groups and the test-types, and the results haven’t varied significantly. And they did other tests to measure motivation rather than performance.
Jacinta: So you mean how seeing red influenced people’s motivation? Presumably negatively.
Canto: Yes. The same research team tried out an experiment on 67 students, based on the assumption that, if you’re an anxious or under-confident employee, you’ll knock on the boss’s door more quietly, and with fewer knocks, than if you’re a confident employee. That’s assuming you find the door closed, and you don’t actually know why you’ve been asked to see the boss. Reasonable assumptions?
Canto: So here’s the set-up. The 67 students were told they would be taking one of two tests: analogies or vocal. The students were shown a sample question from each of the tests, to convince them of the process, though it was all subterfuge basically. They were given white binders, and asked to read the name of the test on the first page. They found the word analogies printed in black ink on a coloured rectangle. The colour was either red or green. Next they were asked to walk down the corridor to a lab to take the test. The lab door was closed, but it had a sign saying ‘please knock’. It was found that those who saw the test title on a red background consistently knocked less often and less insistently.
Jacinta: So they were de-motivated and made more anxious simply by this sight of red. Again, why?
Canto: Learned associations, presumably. Red with danger, with anger, with disapproval.
Jacinta: But – just seeing it on a binder?
Canto: That’s what the evidence says.
Jacinta: Okay – I’m not sure I’m entirely convinced, but all this is a bit negative. Granted we could avoid exposing students to red just in case it inhibits learning, but what about studies that show what might be done to improve learning? That’s what we should be aiming for, surely?
Canto: Okay, so now we’ve eliminated the negative, I promise to accentuate the positive in the next post.
Jacinta: Good, we really need to latch onto the affirmative, without messing with Ms In-between…
Canto: Well, Karl Kruszelnicki is one of our best science popularisers as you know, and therefore a hero of ours, but I have to say his explanation of the blueness of our daily sky in his book 50 Shades of Grey left me scratching my head…
Jacinta: Not dumbed-down enough for you? Do you think we could form a Science for Dummies collaboration to do a better job?
Canto: Well that would really be the blind leading the blind, but at least we’d inch closer to understanding if we put everything in our own words… and that’s what I’m always telling my students to do.
Jacinta: So let’s get down to it. The day-sky is blue (or appears blue to we humans?) because…?
Canto: Well the very brief explanation given by Dr Karl is that it’s about Rayleigh scattering. Named for a J W Strutt, aka Lord Rayleigh, who first worked it out.
Jacinta: So let’s just call it scattering. What’s scattering?
Canto: Or we might call it light scattering. Our atmosphere is full of particles, which interfere with the light coming to us from the sun. Now while these particles are all more or less invisible to the naked eye, they vary greatly in size, and they’re also set at quite large distances from each other, relative to their size. The idea, broadly, is that light hits us from the sun, and that’s white light, which as we know from prisms and rainbows is made up of different wavelengths of light, which we see, in the spectrum that’s visible to us, as Roy G Biv, red orange yellow green blue indigo violet, though there’s more of some wavelengths or colours than others. Red light, because it has a longer wavelength than blue towards the other end of the spectrum, tends to come straight through from the sun without hitting too many of those atmospheric particles, whereas blue light hits a lot more particles and bounces off, often at right angles, and kind of spreads throughout the sky, and that’s what we mean by scattering. The blue light, or photons, bounce around the sky from particle to particle before hitting us in the eye so to speak, and so we see blue light everywhere up there. Now, do you find that a convincing explanation?
Jacinta: Well, partly, though it raises a lot of questions.
Canto: Excellent. That’s science for you.
Jacinta: You say there are lots of particles in the sky. Does the size of the particle matter? I mean, I would assume that the light, or the photons, would be more likely to hit large particles than small ones, but that would depend on just how many large particles there are compared to small ones. Surely our atmosphere is full of molecular nitrogen and oxygen, mostly, and they’d be vastly more numerous than large dust particles. Does size matter? And you say that blue light, or blue photons, tend to hit these particles because of their shorter wavelengths. I don’t quite get that. Why would something with a longer wavelength be more likely to miss? I think of, say, long arrows and short arrows. I see no reason why a longer arrow would tend to miss the target particles – not that they’re aiming for them – while shorter arrows hit and bounce off. And what makes them bounce off anyway?
Canto: OMG what a smart kid you are. And I think I can add more to those questions, such as why do we see different wavelengths of light as colours anyway, and why do we talk sometimes of waves and sometimes of particles called photons? But let’s start with the question of whether size matters. All I can say here is that it certainly does, but a fuller explanation would be beyond my capabilities. For a start, the particles hit by light are not only variable by size but by shape, and so potentially infinite in variability. Selected geometries of particles – for example spherical ones – can yield solutions as to light scattering based on the equations of Maxwell, but that doesn’t help much with random dust and ice particles. Rayleigh scattering deals with particles much smaller than the light’s wavelength but many particles are larger than the wavelength, and don’t forget light is a bunch of different wavelengths, striking a bunch of different sized and shaped particles.
Jacinta: Sounds horribly complex, and yet we get this clear blue sky. Are you ready to give up now?
Canto: Just about, but let me tackle this bouncing off thing. Of course this happens all the time, it’s called reflection. You see your reflection in the mirror because mirrors are designed as highly reflective surfaces.
Jacinta: Highly bounced-off. So what would a highly unreflective surface look like?
Canto: Well that would be something that lets all the light through without reflection or distortion, like the best pane of glass or pair of specs. You see the sky as blue because all these particles are absorbing and reflecting light at particular wavelengths. That’s how you see all colours. As to why things happen this way, OMG I’m getting a headache. The psychologist Thalma Lobel highlights the complexity of it all this way:
A physicist would tell you that colour has to do with the wavelength and frequency of the beams of light reflecting and scattering off a surface. An ophthalmologist would tell you that colour has to do with the anatomy of the perceiving eye and brain, that colour does not exist without a cornea for light to enter and colour-sensitive retinal cones for the light-waves to stimulate. A neurologist might tell you that colour is the electro-chemical result of nervous impulses processed in the occipital lobe in the rear of the brain and translated into optical information…
Jacinta: And none of these perspectives would contradict the others, it would all fit into the coherence theory of truth…
Canto: Not truth so much as explanation, which approaches truth maybe but never gets there, but the above quote gives a glimpse of how complex this matter of light and colour really is…
Jacinta: And just on the physics, I’ve looked at a few explanations online, and they don’t satisfy me.
Canto: Okay, I’m going to end with another quote, which I’m hoping may give you a little more satisfaction. This is from Live Science.
The blueness of the sky is the result of a particular type of scattering called Rayleigh scattering, which refers to the selective scattering of light off of particles that are no bigger than one-tenth the wavelength of the light.
Importantly, Rayleigh scattering is heavily dependent on the wavelength of light, with lower wavelength light being scattered most. In the lower atmosphere, tiny oxygen and nitrogen molecules scatter short-wavelength light, such as blue and violet light, to a far greater degree than long-wavelength light, such as red and yellow. In fact, the scattering of 400-nanometer light (violet) is 9.4 times greater than the scattering of 700-nm light (red).
Though the atmospheric particles scatter violet more than blue (450-nm light), the sky appears blue, because our eyes are more sensitive to blue light and because some of the violet light is absorbed in the upper atmosphere.
Jacinta: Yeah so that partially answers some of my questions… ‘selective scattering’, there’s something that needs unpacking for a start…
Canto: Well, keep asking questions, smart ones as well as dumb ones…
Jacinta: Hey, there are no dumb questions. Especially from me. Remember this is supposed to be science for dummies, not science by dummies.
Canto: Okay then. So maybe we should quit now, before we’re found out…
‘Why is the sky blue?’, from 50 shades of grey matter, Karl Kruszelnicki, pp15-19
‘Blue skies smiling at me: why the sky is blue’, from Bad astronomy, Philip Plait, pp39-47
Quote of the day/week/month/post:
Better to have questions you can’t answer than answers you can’t question – Max Tegmark (and many others)
Jacinta: So while astrophysicists argue over the likelihood of life elsewhere in our tiny but massive universe, some are focusing on our nearest star neighbour. Some wobbling of the red dwarf known as Proxima Centauri has revealed, upon lengthy observation, that it has a closely orbiting planet, which considering the relative coolness of the star – way too dim to be seen with the naked eye – and the proximity of its satellite, is very much in the habitable zone. While it’s too early to say so much for the naysayers, the discovery of a planet in the Goldilocks zone of our nearest star in a galaxy of billions of possibilities must surely raise hopes and expectations of life abundant.
Canto: This closest possible exoplanet was only discovered in August this year, so we’re desperate to find out more about it. Being in the habzone is one thing, habitability is another. Obvious questions we have no current way of answering are: does it have an atmosphere? Any possibility of water? Is it tidally locked? And of course we’d love to know if we could launch some sort of robotic mission to our nearest star neighbour. Meanwhile is there any other way of gleaning more info from this tantalising object?
Jacinta: It’s not likely to be habitable though. Solar winds are estimated to be some 2000 times those experienced on Earth, though we can’t be too sure. Researchers are trying to work out the size of the planet…
Canto: How do they know about those solar winds?
Jacinta: Oooh, that’s a horribly good question. It’s due to the closeness of the orbit, where you would expect the solar winds to be much stronger, as they are in our solar system. It’s believed that Mercury’s magnetic field, which should be stronger than it’s been measured to be because of its heavy metallic core, is dampened massively by our solar wind. So basically they would’ve inferred Proxima Centauri’s wind by our own. As to how they came up with the figure of 2000 times that experienced on Earth, I’ve no idea, but strong solar winds make it hard to maintain an atmosphere, which is vital for life. You’ve also talked about tidal locking, which is a feature of close orbits, such as the Moon’s orbit of the Earth. So you’ll have a permanently hot day side and a permanently cool night side, and this can be problematic for the creation of an atmosphere, according to modelling.
Canto: Now, all of this sounds very negative, but basing exo-planetary activity on what’s been the case, as far as we can work it out, in our solar system, has been really problematic hasn’t it?
Jacinta: Definitely, that’s why we need to go beyond modelling, if we can, and collect some real data. So we’re looking to the James Webb Space Telescope (JWST), the very exciting successor to Hubble to be launched around November 2018, to garner more info, which it’ll be perfectly equipped to do.
Canto: If by some near-miraculous combination of circs there is an atmosphere on Proxima b, or a reasonable quantity of liquid water, that would help distribute the heat around the planet. With no atmosphere, the difference between day side and night side would be stark.
Jacinta: Exactly, and that’s what the JWST should be able to detect, as the best way to detect the atmosphere is to measure the planet’s infrared heat signature. If the JWST finds a decisive and fixed difference between the planet’s day and night sides, it’s a safe bet that no atmosphere is present. The JWST will be equipped to measure this IR signature on both sides of the planet, and if it doesn’t find that stark difference, that’ll be when we can start speculating about an atmosphere and its constituents.
Canto: Though of course they’ve already started with the speculation. But really, whatever they find – and I don’t expect that everything will line up for life – the fact that we’ve found an exoplanet well worth investigating on the nearest star outside our solar system, with billions of stars yet to be homed in on, one by one – doesn’t that say something to those who argue for the Fermi paradox – where are they? Okay, Fermi and Hart were talking about intelligent life, and that may well be orders of magnitude more difficult to develop than life itself, but I’m sure that Fermi would be unsettled in his skepticism, if he was alive today, by the vast numbers of exoplanets, in other words possibilities for life, we’re discovering now, with so many to come in the near future.
Jacinta: Yes, bliss in this time it is to be alive, but to be young, that would be very heaven!
Cosmos issue 71, pp9-10
Canto: So we’re tasked with solving the problem or problems in SA’s energy system.
Jacinta: We are? What problem? Or should I say crisis, what crisis?
Canto: That’s a good question Jass, because as you know the first step in finding a solution is to define the problem.
Jacinta: Yes I knew that. So we’re talking about how all the power died for a period of – what, 24 hours or so, statewide here in South Africa.
Canto: South Australia, don’t confuse our international readers. So I’ve heard the crisis framed in a number of different ways. First, in terms of the SA government’s irresponsible, unrealistic go-it-alone pursuit of risky renewable energy. Second, in the more or less opposite terms of other states’ and especially the federal govt’s foot-dragging and negative approach to said energy, leaving SA unsupported. Third, in terms of privatisation – a number of electrical pylons fell down like ninepins in the outback, because, it’s claimed, the private owners are pursuing profits over infrastructure maintenance. And a fourth and most comprehensive framing invokes climate change itself – SA was subjected to an unprecedented weather event likely caused by the emissions our gallant state government is trying to reduce..
Jacinta: And our little Torrens River has been torrenting like the mighty Amazon.
Canto: Yeah right. So with all these and more framings of the problem, it looks like we’ll have to spend a few posts on this issue.
Jacinta: Or a lifetime. But yes let’s try to be thorough. And positive. I thought we might start with the 9-point plan for solutions to complex problems which we found in the enlightening book The origin of feces by Stuart Waltner-Toews, and which was presented in simplified form on the Solutions OK blog.
1. What is the problem situation or issue? How did it come to be a problem?
2. Who are the stakeholders? What do they care about? Where are they coming from (motives, investments)? What are the agreements, discords among them?
3. What are the stories being told by these different stakeholders re their roles and concerns in the problem?
4. What’s our best systematic, scientific understanding of the situation/problem?
5. What’s our best understanding of the social & cultural issues to be addressed?
6. How are 4 & 5 related? How do they constrain or support each other?
7. What are the scenarios and narratives here that people most connect with? On what things can we agree on? What are the power relations between people who agree or disagree? Given these constraints and acknowledgements what do we realistically expect that we can do?
8. What course of action, governance structure and monitoring system will best enable us to implement our plans and move towards our goals?
9. Implement. Monitor. Adjust. Learn. Re-Start.
Canto: Yeah, that’s pretty comprehensive all right, maybe too comprehensive.
Jacinta: No I think it’s a good basis. Take point 1. What’s the problem? That’s easy. The problem is that SA had all its power cut for the best part of a day, and although many are saying this was a one-off, freak event, many others are saying it could happen again and that SA’s the most vulnerable state, it wouldn’t have happened to any other state.
Canto: Though I think our Premier said the exact opposite, it could’ve happened anywhere. Lots of conflicting narratives and opinions. So let’s get started.
Jacinta: Well let me first say that, whatever the cause, we are experiencing extreme weather here for October – rainy and stormy conditions which have certainly never been experienced here in a good long lifetime. And right now we’re got rain and strong wind conditions. There’s been little let-up for some time.
Canto: Interesting – we’re only a few days into October, but the average rainfall for September in Adelaide, since records have been kept, is about 58 millimetres. This year it was over 130 millimetres. October, though, might be the most interesting month for records. Certainly I can’t recall anything like this, and we have flooding in many parts of the state.
Jacinta: So we have extreme weather conditions, and the direct cause of the outage, according to our Premier, was freak weather conditions north of Adelaide, including two tornados which knocked over transmission towers near Melrose. More than 20 transmission lines were damaged. The question being asked, of course, is how could these storms knock out the power for a whole vast state for a long period? What were the back-up arrangements?
Canto: Well the back-up apparently relies on two interconnectors to the east coast. Presumably there must be some arrangement so that when local power isn’t forthcoming, the interconnectors receive a signal to transmit. However, only one was operational at the time of the outage. Now I don’t really understand this interconnector thing and how they work. I’m not clear on why one interconnector was shut down and why the other one didn’t just do the job. Is it just a matter of ‘firing up’ an interconnector and a whole state’s lights come back on? How simple or complex is it?
Jacinta: And what, if anything, has this got to do with renewable energy and the shutting down of the coal power station in Port Augusta?
Canto: We might get to that later. I haven’t been able to find exactly how interconnectors work, and nothing much at all on interconnectors in Australia, but currently in the UK there are four interconnectors, linked to France, the Netherlands, Northern Ireland and the Republic of Ireland, of which the France one is largest, with 2GW capacity. It would be interesting to know the capacity of the two interconnectors linking us to the east, and whether that has any relevance. Anyway, these interconnectors are spruiked as providers of energy security and flexibility, so the more interconnectors the better. Maybe there’s a case for having a third interconnector, so that we’re never, or rarely reduced to having just one to rely on.
Jacinta: So why did we have no power? Why didn’t the interconnector provide it for so long? Or was it the interconnector that provided it, or was it the local system?
Canto: Well there was certainly local work going on from the start, as soon as conditions allowed, to fix local faults, but I can’t find too much info on the role of the interconnector. However, word has just come out that there’ll be a state inquiry into South Australia’s unique situation, so maybe there’s no point in us continuing this conversation.
Jacinta: Wait up, I think it might be fun speculating on and researching the matter, and then comparing our findings with the inquiry.
Canto: Which’ll come out in, what, five years?
Jacinta: An unnecessarily jaded remark. So let’s get stuck into some research, and look for solutions, always keeping in mind that 9-point plan.
Okay I’ve written facetiously about getting rid of men, or seriously (but facetiously) reducing their proportion of the populace, but in future I want to look at real solutions to a problem that I think is already being addressed but far too patchily and slowly – the problem of male power and dominance. The general solution, of course, is the ascent of woman, to paraphrase Jacob Bronowski via Darwin, and how to promote and quicken it. (Incidentally I’ve just discovered that ‘The Ascent of Woman’ is a four part documentary on women’s history, recently produced for the BBC by Dr Amanda Foreman – look forward to watching it).
However, before continuing I want to issue a plea for help. My blog, which I’ve been writing for many years now, has never had much of a readership, due probably to my inability to network, or even communicate much with others (I’d rather not think it’s anything to do with my writing skills). However, last month even that minuscule readership virtually collapsed, as I recorded my lowest number of hits since my first month of blogging. I’ve soldiered on, but now at the end of September I find this month’s numbers even worse. I feel I need to make a decision about the blog’s future – How do I increase the numbers? Does the blog need a makeover? Can I blame the attention-span of others? I find if I write short pieces, they don’t really cover anything in depth, but I know also that the in-depth pieces, the ones I work on hardest, often get the least attention. Should I just give up and go back to journal writing? At least that way I won’t be faced with the world’s indifference…
Anyway, enough about me – it’s interesting that when you start focusing on an issue, you hear about it everywhere, everybody seems to be talking about it. Today, listening to a podcast of the ABC Science Show, I heard that teenagers are our biggest killers, worldwide, predominantly through motor vehicle accidents. And of course we’re talking largely of male teenagers. The researcher announcing this was female, and, typical female, she was complaining about us tackling this old problem (this has been the global situation for some sixty years) in the same old piecemeal way, rather than though global collaboration in researching and trying to figure out workable solutions to what is clearly a global problem. It was clear from this passionate speaker (and mother of teenage children) that with more females leading research in this and other fields, we’ll get more collaboration and quicker and more effective solutions. And when Robyn Williams, our honourable Science Show anchor, asked the researcher a double-barrelled question – is this teenage problem a male one, and should teenage boys be banned from driving? – her honourable response was ‘yes, and yes’.
The question is – would a law specifically targeting boys/young men as drivers ever be implemented? Of course, many males would describe it as discriminatory. And of course it does discriminate, because the statistics are clear. But why, a young male might ask, should I be treated as a statistic? I’m not like other young men.
It’s a valid point, and I can’t see an obvious way of screening out the potentially safe young men from the potentially dangerous ones. So all we could acceptably do is raise the driving age for all, preferably globally, which would effectively discriminate against the statistically safer drivers, the females. Still, I like the idea of a push, led in the main by women, for a discriminatory driving age policy backed by science. It would raise the profile of the issue, bring women together in an excellent cause, potentially save lives, and feature as another small episode in the ascent of women.
Of course it wouldn’t solve the terrible wee problem of young kids stealing cars and killing and maiming others and themselves for pumped-up kicks…
There is more global investment in solar power today than there is in fossil fuels. We’re talking about hard-headed investment for profit by business and governments worldwide, not greenies or special interest groups. And another interesting factoid: China today is generating more energy from wind power than the whole of Australia’s energy production. Not to mention the Chinese government’s massive investment in other renewables. That’s info I got from a recent ABC Science Show podcast. Renewable energy really is making inroads, and this is most encouraging for those around the world fighting the damaging environmental effects of mining and fracking in their regions, though it’s clear that such operations are dying hard.
I remember some time ago at a meeting of skeptics (not climate change ‘skeptics’, just regular sciencey anti-quackery, anti-UFO-type skeptics), when I was spruiking the virtues of wind power, so successfully taken up here in South Australia, being told dismissively that it was too expensive to be really viable. However, wind-power only really has establishment costs. Ongoing costs are quite minimal. Furthermore, a research group conducted by the Carnegie Institution for Science’s Global Ecology Department has recently conducted the most wide-ranging expert survey on wind (or any other) energy. Sure, it was a survey of those already heavily invested in wind, but that does make them the experts in the field. Predictions about the cost of wind energy into the future were based on two approachess. First, a projection into the future of falling costs over the past three decades or so – what they call the ‘learning curve’. One would assume those projections would vary from ‘most optimistic’ to ‘most pessimistic’, with consensus somewhere in between. The second approach involved a ‘bottom-up engineering assessment’, looking at the costs of individual turbine components into the future. Science Daily has summarised the findings:
On average, the participants expected wind power costs to continue falling for the next several decades, for three major classes of wind turbines, both onshore and offshore, with prices falling by 24-30% by 2030, and 35-41% by 2050.
Meanwhile governments worldwide are getting on board in a determined effort to drive down the cost of solar. Vox Energy & Environment reports on the US target:
…the US Department of Energy has a program, the SunShot Initiative, devoted entirely to driving down the cost of electricity generated by solar panels — the target is solar power with $1 per watt installed costs by 2020, a 75 percent reduction in costs from 2010.
It’s hard to get the head around the growth of solar energy worldwide since about 2007. It’s been a whirlwind ride, but starting from an extremely low level. And in the US since 2012, large or utility-scale solar has been growing faster than domestic, rooftop solar, and with falling prices and increasing module efficiency, the growth trend in big and small solar should continue well into the future. Yes, there’s government stimulus, but solar is being seen more and more as a sound investment on its own terms. Solar’s steady growth also makes for sound investment against the high volatility of the natural gas market. And this of course is just as relevant for many regions outside the US.
I’ll be taking another look at Australia’s situation, while many of our governments bicker and focus elsewhere, in an upcoming post.
Men are bigger than women, slightly. That’s how things evolved. It’s called sexual dimorphism. It happens with many species, the genders are different in size, shape, coloration, whatever. With humans there’s a size difference, and something of a shape difference, in breasts and hips, but really these aren’t significant. Compare, say, the deep-water triplewort seadevil, a type of anglerfish, in which the female is around 30 cms long, and the male a little over a centimetre. The difference in mass would be too embarrassing to relate.
Among our primate cousins the greatest sexual dimorphism, in size as well as other features, is found in the mandrills, with the male being two to three times the size of the females. In some gorillas there’s a substantial size difference too in favour of the males, and in fact in all of the primate species the male has a size advantage. But size isn’t everything, and the bigger doesn’t have to always dominate.
Female bonobos are smaller than the males, even more so than in humans, yet they enjoy a higher social status than in any other primate society, probably including humans, though it’s hard to compare, since humanity’s many societies vary considerably on the roles and status of women. So how have females attained this exalted status within one of the most highly socialised primate species?
Bonobos and chimpanzees are equally our closest living relatives. It isn’t clear when exactly they separated from each other, but some experts claim it may have been less than a million years ago. Enough time for them to become quite distinct physically, according to the ethologist Franz De Waal. Bonobos are more gracile with longer limbs and a smaller head, and they have a distinctive hairstyle, with a neat parting down the middle. They’re also more easily individuated by their facial features, being in this sense more like humans. And there are also major differences in their social behaviour. Male chimps are dominant in the troupe, often brutally so, whereas bonobo society is less clearly hierarchical, and considerably less violent overall. De Waal, one of the world’s foremost experts on both primates, became interested in bonobos primarily through studies on aggression. He noted that sometimes, after a violent clash, two chimps would come together to hug and kiss. Being interested in such apparent reconciliations and their implications, he decided to look at reconciling behaviours in other primates. What he discovered in bonobos (at San Diego Zoo, which in 1983 housed the world’s largest captive colony) was rather ‘shocking’; their social life was profoundly mediated by sex. Not that he was the first to discover this; other primatologists had written about it, noting also that bonobo sex was far more human-like than chimp sex, but their observations were obscurely worded and not well disseminated. There are other aspects of the physical nature of sexual relations in bonobos that favour females, such as female sexual receptivity, indicated by swelling and a reddening of the genital area, which pertains for a much longer period than in chimps. Female bonobos, like humans and unlike other primates, are sexually receptive more or less all the time.
This isn’t to say that bonobos are oversexed, whatever that may mean. Sexual relations are far from constant, they are casual, sporadic and quickly done with. Often they’re associated with finding food, and it seems likely that sexual relations are used to reconcile tensions related to food availability and other potential causes of conflict.
So how does this use of sex relate to the status of females in bonobo society. I’ll explore this further in the next post.