Canto: So I happened to watch an excellent video from the Royal Institute recently, a talk by the beautifully named and beautifully voiced Irish geneticist, Aoife Mclysaght…
Jacinta: How do you pronounce that?
Canto: It’s pronounced Aoife Mclysaght…
Jacinta: Oh right.
Canto: So the theme was that everything in biology makes sense only in the light of evolution, and she was illustrating this through her area of interest and research, gene duplication. And along the way she talked about trisomies, particularly trisomy 21, usually referred to as Down Syndome.
Jacinta: A trisomy involves having an extra copy of a chromosome, in this case chromosome 21.
Canto: Very good, and the extra copy is a perfectly good copy, but having that extra copy causes major problems, obviously.
Jacinta: The term ‘trisomy’ refers of course to three – having three rather than two sets of a particular chromosome. Humans normally have two sets of 23 chromosomes. I have a relative who has a rare and unnamed form of trisomy, or at least a rare form of chromosomal disorder, which, when looking into it, I decided must be a trisomy. But since then I’ve discovered that Williams syndrome – which I learned about from another person I know with that condition – isn’t a trisomy, but the result of genes missing from chromosome 7. So now I’ve gone from thinking that trisomies accounted for all or most sorts of genetic intellectual disabilities to… I don’t know.
Canto: To a position of deeper ignorance. So people with trisomies have 47 chromosomes, with Down syndrome being the most common. Others include Edward syndrome (trisomy 18) and Patau syndrome (trisomy 13). Interestingly, though, there’s another rarer form of Down syndrome that’s due to translocation – that’s when a part of a chromosome – in this case chromosome 21 – migrates to another chromosome, usually chromosome 14, during cell division
Jacinta: That complicates matters… So do we know what causes these trisomies, and these translocations? They seem to be very specific, occurring for only particular chromosomes, or bits of them.
Canto: Well you’re right in that trisomies 21, 18 and 13 are relatively common – I mean rare but more common than a trisomy 9 or 15 or 19, just to pick out any numbers less than 23. We do know that trisomies become more common with older egg cells. As you know, your egg cells are as old as you are, and they become a little decrepit with age like yourself.
Jacinta: We’re both slouching to oblivion.
Canto: It’s also the case that most trisomies don’t survive to term, in fact they mostly miscarry so early that the mother doesn’t even know she’s been pregnant. So presumably those trisomies I just picked at random, if they occur at all, have more fatal consequences. It seems in any case that a trisomy occurs when cells divide but one chromosome somehow sticks to its homologue and is carried with it into the new cell. So maybe some chromosomes are more ‘sticky’ than others?
Jacinta: I think we need to do a deeper dive, as one pundit likes to say, into meiosis and aneuploidy.
Jacinta: That’s just when you have an abnormal number of chromosomes per cell: it could be less or more. Actually trisomy 16 is the most common form, but fatal in its full-blown version. It can exist in mosaic form – when not all the cells have it.
Canto: So can you explain meiosis for us?
Jacinta: A long story but fascinating of course. It’s the basis of sexual reproduction for all eukaryotes. So before eukaryotic germ cells or gametes divide they need to replicate their chromosomes so that the resulting pair of cells has an equal share. This period of replication is known as the S phase.
Canto: Wait a minute, does this mean that in the S phase humans have 92 chromosomes per cell instead of 46?
Jacinta: Don’t bog me down with clever questions. Taking another step back, we have this whole process called the cell cycle, which we divide into phases. We can start anywhere, since it’s a cycle, if you know what I mean, but if you need a beginning it’s the prophase. Anyway, the S phase comes after the G1 phase and before the G2 phase. S, by the way, stands for synthesis, and G here stands for gap. Together these three phases make up the interphase, at the end of which we have the prophase of a new cell cycle, though actually meiosis isn’t a cycle the way mitosis (non-sexual reproduction or cell division) is. To be accurate, the next phase is called prophase 1, which is followed by metaphase 1, anaphase 1 and telophase 1 before we have prophase 2….
Canto: Stop cycling I’m getting dizzy.
Jacinta: Well yes believe me it’s complicated, and I haven’t begun yet. But you did ask for it.
Canto: Can you give the simplified version?
Jacinta: Not really.
Canto: Okay, we’ll leave that for another day. Focusing in on the part of meiosis when these trisomies and other anomalies occur, it seems that the problem isn’t so much stickiness as non-stickiness. Think of gametes. In mammals such as humans there are two types, egg and sperm cells. They’re differentiated by their sex chromosomes, chromosome 23…
Jacinta: And also by the fact that the egg cell is like the sun and the sperm cell is like the earth.
Canto: Well, sort of, in terms of volume. Now, after meiosis – which occurs in phases, meiosis 1 and meiosis 2, creating two daughter cells then four grand-daughter cells, so to speak – each of these grand-daughter gametes should be haploid. That’s to say, they should contain only one of each of the 23 chromosomes. But nothing’s perfect and sometimes there are errors, and we’re not clear about why, though the chances of error rise with the age of the female as mentioned before. Mostly the problem is that the chromosomes didn’t properly separate, a state called chromosome nondisjunction. Something to do with the spindle apparatus not functioning properly due to a lack of cohesion of the chromosome. This occurs rather more frequently in female meiosis, or oogenesis, than in male meiosis, or spermatogenesis, they’re not sure exactly why.
Jacinta: Well I must say that’s all very enlightening, and salutary, as it’s made me aware of how little I know about genetics in general. Now I know a teensy bit more. As to trisomies and other such chromosomal problems, what they know just makes me keen to know more about how we might detect them and possibly in the deep future rectify them at source. But the science is clearly a long way from that…
Canto: Well you never know. Genetics is a fast-moving field.
Jacinta: we must explore it more. It’s serious fun.
Canto: So what’s on the agenda for 2016 here at the new ussr?
Jacinta: Well I’m hoping we can do a ‘deep dive’, as one researcher likes to put it, on GMOs, another polarising subject, with a few posts, and maybe at least one on Monsanto, the supposedly evil capitalist monster that the anti-GMO crowd love crusading against…
Canto: Good, and I’d also like to focus a bit more on climate change, the ever-developing science of monitoring this complex beast, as well as the clean energy responses.
Jacinta: Including nuclear?
Canto: Well of course I don’t want to shy away from its potential, or its problems.
Jacinta: So no more black holes and cosmic webs?
Canto: I’d love to cover everything, if I had but talent enough, and time.
Jacinta: Yes and I’d like to find time for some philosophy as well, say on the limits of science, if any. But okay let’s get started on climate. I know you’ve been thinking about the ‘Climate Watch’ segment in the most recent issue of Cosmos, Australia’s most excellent science mag.
Canto: Yes, so while we’re congratulating our leaders (or not) on coming to an agreement re targets for global warming, we need to keep our eyes on the changes already underway, which many have been warning for years might lead to runaway, unstoppable warming.
Jacinta: Feedback loops and cascading effects.
Canto: Precisely, and one of the most serious, because unpredictable, changes we’re witnessing is in the arctic permafrost.
Jacinta: Which presumably is becoming less perma and frosty.
Canto: It’s thawing out, releasing large volumes of methane from the microbes that have been frozen there for many centuries.
Jacinta: And that’s a biggie in terms of greenhouse gases. So why do these presumably dead organisms release methane? I thought all our methane came from cow farts.
Canto: Did you really? Methane is released by rotting organic matter. You have peas in your freezer? Yes? So can you smell them? Very unlikely in their frozen state. So dig out a handful and stick them out in our summer sun. Pretty soon they’ll start to smell. What are you smelling?
Jacinta: Uhh, methane?
Canto: You’re quick. Amongst other gases of course – pure methane doesn’t stink like that. And because methane is such a potent greenhouse gas its release speeds up the thawing process, which could lead to a kind of tipping point, but the extent of this speeding up process, the amount of methane currently being released, and how it will affect the overall warming, these are horrendously difficult values to predict.
Jacinta: And methane’s essentially what we call natural gas isn’t it? CH4? So it’s another carbon-based product.
Canto: Yes, and twenty times more potent than CO2 as a greenhouse gas, according to climate scientists.
Jacinta: And the process we call rotting, that’s actually bacterial, isn’t it? Is it that these microbes release methane, inter alia, the way that we release CO2, after breathing in oxygen?
Canto: You’re talking about methanogens, which are actually archaea rather than bacteria. They thrive in anoxic, or low oxygen conditions, such as wetlands, but also in the digestive tracts of ruminants, indeed in most animals including humans. We release methane when we fart.
Jacinta: Some more than others. So I suppose the permafrost contains all these archaea, or they multiply when it starts to thaw?
Canto: They’re unlocked or reawakened by the thaw, and then, recent studies have shown, they can pump out methane at a phenomenal rate. And there’s a lot of permafrost involved at the moment, in land not under ice, including about half of Russia and Canada, and much of Alaska. They reckon there’s about 1.7 trillion tonnes of carbon trapped in this permafrost, twice the amount of atmospheric carbon.
Jacinta: So how much is likely to be released?
Canto: Nobody really has any idea, that’s the problem. One study has suggested that almost a tenth could be released by 2100, which doesn’t sound like much, but this effect hasn’t been factored in by the Intergovernmental Panel on Climate Change because it’s so hard to calculate – some of the microbes will be methanogens, some will be more liable to release CO2, depending on the local environments created by the thaw. Clearly it’ll be negative though, and will just add pressure and urgency to our plan to keep global warming down.
Jacinta: Yet I thought that the regions you mentioned, those permafrost regions, were full of evergreen forests – the taiga I think is the name. And they’re a carbon sink rather than a source of emissions.
Canto: You’re right, that’s another factor. In fact the taiga is a huge carbon sink, the biggest land sink on earth, but with climate change, the whole permafrost region is becoming less of a sink and more of an emitter, perhaps for the first time. The effects, as I’ve said are very difficult to predict, because the thaw is occurring at different rates, affecting different micro-climates, and with vastly different results even within metres. Being frozen has a uniform, more predictable effect. The thaw unlocks huge varieties of ecosytems – life in all its blooming buzzing confusion.
Jacinta: Well it does sound kind of fascinating in itself, apart from the disturbing effects…
Canto: Spoken like a true disinterested scientist.
Jacinta: I believe the federal government is bringing in new rules penalising parents who choose not to vaccinate their children. Do you know the details, and how do you think the anti-vaccination movement, which is quite strong in Australia, is going to react?
Canto: Well, first I’ll note that when looking up this issue on the net I found a disproportionate number of anti-vaccination or ‘vaccination skeptic’ sites cropping up on Google. It’s very disheartening that the ‘AVN‘, formally deceitfully titled the Australian Vaccination Network, now forced by law to call itself the Australian Vaccination-skeptics Network, comes up first all the time. Other depressing sites that come up include nocompulsoryvaccination and ‘natural society‘. These appear to be US sites promoting the ‘nature is better’ fallacy or some dubious form of libertarianism, and I suppose they have ways of maintaining a high internet profile.
Jacinta: Well, this is the thing, they have a ’cause’ to rally around, whereas the immunologists and doctors who know the science don’t see what the fuss is about, and just assume that everybody respects scientific methods and results. Which is obviously far from the case.
Canto: Well anyway yes the federal government, and the Victorian state government, have created bills to better enforce vaccination, and the Australian government’s measure came into force on January 1. Child care payments and family tax benefit part A supplement will only be paid for children who’ve been immunised or have an approved immunisation exemption.
Jacinta: So, can you get an exemption easily, due to your firm belief that vaccinations cause diabetes, or autism or whatever?
Canto: Only on religious grounds.
Jacinta: Ahh, but can’t the refuseniks claim to be religious, since they have very strong beliefs based on no evidence?
Canto: Ha, well, I’m sure they’ll try. And actually I think it’s going to be difficult for the government to enforce this one.
Jacinta: Why should it be? Surely they have immunisation records through Medicare, it would be easy enough to check.
Canto: And what if the child spent the first few years of life overseas? And what if a parent insists the child was immunised but there’s no record?
Jacinta: Mmmm, I think these are minor difficulties, and I belief it has a support level of over 80%.
Canto: Yes so we’ll have to wait and see what plans the AVN have to try and sabotage it. Other state governments, in Victoria, Queensland and possibly elsewhere, are introducing measures in harmony with this, so it does seem to deal a serious blow to the refuseniks. And of course it’s hoped, or expected, that it’ll bounce the fence-sitters off the fence and so increase community immunity.
Jacinta: And that reminds me, I was reading somewhere about anti-vaccination hotspots. Any info on that?
Canto: Well yes, they’re the places to look to for trouble. The low-down on all that can be found at this slightly unlikely source, Mamamia, an entertainment and lifestyle website – and good on them. It also has a graphic from the Department of Health that reveals the alarming rise in ‘conscientious objectors’ to vaccination in Australia over the last 15 years, from 4000-odd in 1999 to over 36,000 in 2013.
Jacinta: So does it mention anywhere in South Australia?
Canto: Yes, and I’ve noticed that these hotspots are often in quite affluent regions…
Canto: Yes, the Adelaide Hills region, which I would think is generally quite affluent, has one of the highest objection rates, with 86% of children under 5 vaccinated compared with the state average of 91.5%. But then they say that many other areas are under 85%, including Port Adelaide, Holdfast Bay – that’s the Glenelg region, and Playford. So a mix of semi-affluent and relatively disadvantaged regions. Hard to make sense of it, but I think there’s a distinction to made here between the refuseniks and those who just don’t get round to vaccinating their kids.
Jacinta: Right, and that wouldn’t necessarily come out in the data.
Canto: Yes, some are slackers and some are refuseniks.
Jacinta: And some might be fence-sitters who might be spurred into getting their kids vaccinated by this stick approach.
Canto: Yeah we’ll have to wait and see whether the unvaccinated numbers go down over the next few years.
Jacinta: Which makes me wonder, how do they know that those figures you quoted before – some 36,000 – were ‘conscientious objectors’?
Canto: Well they probably don’t for sure, but it’s highly unlikely that those numbers have gone up by almost a factor of 10 in fifteen years due to sheer complacency. I mean, is it plausible that in the last 15 years or so we’ve become 10 times more slack as a nation about our children’s health? No, there’s something much more disturbing going on. Mamamia quotes a Melbourne virologist, who claims that in some pockets of the nation our immunisation rates are lower than South Sudan.
Jacinta: Oh well done. I’m guessing they enforce vaccination in South Sudan, or I might be suffering from the delusion that most African governments are brutal dictatorships. Anyway, what are the biggest or worst hotspots nationally? I’m thinking Nimbin.
Canto: Yes, that area – Nimbin, Byron Bay, Mullumbimby, that whole northern New South Wales coastal area has vaccination rates down between 60% and 70%. Mullumbimby is the town with the highest objection rate in Australia, and the lowest immunisation rate, at under 50%. Steiner schools are popular in this region, unsurprisingly, and they’re openly promoting refusenik behaviour. But there are many other problem regions, such as Queensland’s Gold Coast and Sunshine coast. Noosa on the Sunshine coast also has very high objection rates.
Jacinta: These are quite wealthy areas I suppose. Any idea why this is happening?
Canto: Well, I can only speculate, but I think, with wealthy people, there’s a greater degree of resistance to government measures, obviously in the case of taxation, but also with health matters. They’re rich, they’re healthy, they feel they’re already immune, and that if they just maintain a healthy lifestyle they’ll be fine. Clearly they’re not particularly informed about the benefits of vaccination, or choose to believe those benefits are exaggerated. I suspect that the further we remove ourselves from the bad days of TB, diphtheria, mumps and measles, the more we’ll get this creeping belief that vaccines are over-rated. The positive thing, though, is that we still have some 83% of parents in favour of some kind of punitive measure for those who don’t or won’t vaccinate their kids. But I do suspect that percentage will reduce over time. We humans have short memories and an over-supply of hubris, it seems to me. Or perhaps we’re just a bit over-confident with respect to our survival mechanisms. We’re like teenagers, we rarely listen to our parents – they’re history, after all. We need a few life-blows to counter our cockiness.
Jacinta: Hmmm, grim but probably true. Anyway, the government has acted and that might reduce the number of fence-sitters, even if it polarises the issue a bit more.
Canto: Well I’ve just managed to finish reading Naomi Klein’s great big book about the politics of climate change, This changes everything, and since this more or less coincides with the recent political decisions made about tackling climate in Paris, I thought we might spend this session, or even a few sessions, on the future of clean energy, the fossil fuel industry and so forth.
Jacinta: Ah yes, the Paris conference, can you fill me in on that? All I know is that the outcome is being touted as a turning point, a watershed moment, but I presume none of it is enforceable, and I can’t really see the fossil fuel giants giving up the ghost, or considering anything much beyond business as usual…
Canto: Okay, the UN climate change conference in Paris ended on December 12 2015, having run for about 3 weeks. The principal outcome has been the Paris agreement, which was a more substantive agreement on emissions reduction than has been achieved in the past. It apparently represents a consensus drawn from some 196 national representatives.
Jacinta: And I seem to recall the figure of 2% being bandied about. What was that about?
Canto: Ummm, I think you might be referring to the plan, or hope, to limit global warming to 2 degrees, through zero net greenhouse gas emissions in the second half of the 21st century, globally.
Jacinta: Wow, that’s some hope.
Canto: Well the hope is to keep the warming to well under 2 degrees C, preferably aiming for 1.5, which would entail substantial reductions well before 2050, but of course this is all promises, promises.
Jacinta: So what about enforcement, and how is this going to be achieved nation by nation, considering that some nations are huge emitters, and some nations, like India, are still developing and industrialising?
Canto: Right so there are all these semi-commitments and promises, but crunch time starts in April 2016, from which time the relevant parties are asked to sign up to the agreement – that’s 197 parties in all, including all member nations of the UN, the European Union and some not-quite-nations like Palestine and the Cook Islands. They have a year to sign up, and the agreement will only come into force if 55 countries that produce 55% of global greenhouse emissions sign up.
Jacinta: Wait, does that mean all of the top 55 greenhouse gas emitters, or any 55 that together emit 55% of the greenhouse gases emitted by humans?
Canto: Uhhh, I’m not sure but I think it’s the latter.
Jacinta: Great, so Australia doesn’t have to sign. Quel soulagement!
Canto: Funny that, because the Wikipedia article on the Paris agreement, specifically mentions the climate change ‘skepticism’ of our conservative government…
Jacinta: Wow, what an honour.
Canto: Time to lobby our environment minister. Of course there are a lot of people protesting that this agreement doesn’t go far enough – not so much in the targets as in the voluntary nature of it all. I mean, it may not even come into voluntary force if nations don’t sign up to it, and of course there’s no enforcement mechanism. Here’s how Wikipedia describes the situation:
The Agreement will not become binding on its member states until 55 parties who produce over 55% of the world’s greenhouse gas have ratified the Agreement. There is doubt whether some countries will agree to do so. Each country that ratifies the agreement will be required to set a target for emission reduction, but the amount will be voluntary. There will be [no] mechanism to force a country to set a target by a specific date and no enforcement if a set target is not met. There will be only a “name and shame” system or as Janos Pasztor, the U.N. assistant secretary-general on climate change, told CBS News (US), a “name and encourage” plan.
Jacinta: Well I think it’s definitely a positive development, which will add pressure to the fossil fuel industries and their supporters. I notice that one of our green pollies was castigating the government the other day about the expansion of the Abbott Point coal terminal, citing the Paris agreement. That’s going to be a much repeated dagger-thrust into the future. So how does this all connect with Naomi Klein’s book?
Canto: Well I think you’re right to accentuate the positives. I mean, how can you seriously police or enforce such an agreement without interfering with the ‘national sovereignty’ that so many nations bellow about – especially when there’s a hint of criticism from the UN? So the first real positive coming from this confab is that all the parties are in agreement about the imminent threat of AGW, and they’ve actually managed to come to a broad agreement over a target and a goal. That’s a big deal. The second positive is, as you say, the impact of that consensus on the battle against the cashed-up fossil fuel industries, and the mostly conservative governments around the world that are still into science denialism, including our own government. As to This changes everything, Klein sees the AGW issue as a possible game-changer for the politics of global capitalism and free marketeering, which is rather ambitious, but she puts her faith in the protest movements, the indigenous rights movements and other grassroots movements who are, as she sees it, rising up more than ever before to create headaches for the business-as-usual model. She calls this grassroots approach ‘blockadia’, probably not an original coinage.
Jacinta: So she sees it as an issue to fight global capitalism, to replace it with… what? Surely the renewable energy industries are capitalist industries too?
Cant: Well yes, I think there’s a certain amount of idealism in her view, an old-fashioned back-to-nature ethic, and I don’t think she emphasises the solutions and the science as much as she emphasises the problems and the politics, but if you take the view that the fossil fuel industries need to be phased out, sooner rather than later, you’ll perhaps be as much inspired by the heroic and hard-working efforts to prevent mining and drilling – which, let’s face it, have caused huge devastation in many areas – as you will by the innovations and improvements in clean energy. Which brings me to the other term used a lot in Klein’s book – extractivism.
Jacinta: Which presumably stands not just for the fossil fuel industry but the whole mentality of ‘what can we extract from this entity?’, be it animal vegetable or mineral.
Canto: The ancient Greeks did it with their slaves, the British did it with their colonies…
Jacinta: And their slaves..
Canto: The tobacco industry are doing it with the resource of willing smokers in non-western countries, poachers are doing it with elephants in Africa, the porn industry is doing it with pretty and mostly impoverished girls in the US and Europe, multinational companies are doing it with cheap labour worldwide. Extractivism has always been with us…
Jacinta: Point taken but I think we’re getting a bit carried away here. I presume Klein was using the term in a more limited sense, though perhaps with a nod to broader extractivist tendencies. And I have to say, quite apart from the devastation caused by tailings and disasters like Deepwater Horizon, I’ve always felt there’s something not quite right about our recent cavalier exploitation of a process of incredibly slow transformation of once-living and evolving entities – our ancestors in a sense – into coal and oil. Doesn’t it seem somehow sacrilegious?
Canto: Well perhaps, but I’m not sure if ‘exploitation’ is the right word. People get exploited. Okay animals can get exploited. But dead matter turning into coal? All species do what they can to survive and thrive, and they don’t worry about the cost to others or to historical processes. Right now parrots are feasting on my neighbour’s fruit trees. They’re extracting what they can in one go, and they’ll be back for more unless someone stops them. My neighbours might consider the parrots a pest, but that’s only because they want to extract as much as they can from those trees, to make jam, or to add fibre and other nutritional elements to their diet. As to the fossil fuels I’m all for keeping them in the ground, but more because of the damage they do to our atmosphere than because it’s ‘nice’ and ‘respectful’ not to extract them.
Jacinta: Spoken like a true instrumental scientist, but I can’t help feeling there’s more to it than you say. But what do you think about the view that this is a game-changer for global politics? Klein subtitles her book ‘capitalism v the climate’, as if one or the other has to come out on top. Do you think that’s really the choice?
Canto: No I don’t, but I doubt that Klein really imagines, or even wants this to spell the end of capitalism. I’m no anti-capitalist of course, but then I see capitalism in much broader terms. Those parrots are capitalising on a resource previously unavailable to them, and they’ll continue to do so unless prevented, by netting or something worse. Fossil fuel companies have learned to capitalise on a resource previously unavailable to them, before we learned how to process and extract energy from such material, and they’ll continue to do so unless they’re prevented, by legislation, by blockadia, or by the availability of more attractive alternatives, such as the more effective exploitation of the sun. Or capitalising on the solar resource.
Jacinta: So you believe that all humans, or rather, all creatures are capitalists? Isn’t that a bit of a narrow view?
Canto: Well no, as I say, I think it’s a broad view of the capitalist concept. But of course you might say that this hardly accounts for blockadia. If we’re all capitalists at heart, how do we account for the amount of energy so many citizens put into blocking capitalist exploitation? But that’s easily explained by the parrots and fruit example. The parrots’ gain is the neighbours’ loss. The neighbours have gone to a lot of trouble cultivating the ground, planting the trees, watering and fertilising, and these pesky parrots have come along without so much as a by your leave, and devastated the crop. Similarly farmers who have put a lot of time and energy into cultivating their land, and indigenous people who have learned over generations how to fish and hunt in an area in such a way that stocks can still be replenished rather than devastated, are naturally outraged that these fossil fuel companies have come along and ‘poisoned the well’. The farmers and the indigenes are also capitalists, very effective capitalists for their own needs, but they’re faced with different types of capitalists with different needs. So, to me, it’s a matter of resources, needs, diversity and negotiation.
Jacinta: Hmmm, well I’m inclined to agree with you. Of course indigenous people, such as our Aborigines, like to talk of spiritual connections to the land and its bird and animal life, but I’m not much into spirituality. But I like the idea that even though they’re into hunting and killing those creatures in order to survive, they tell stories about them, and exhibit a great deal of respect and fondness for them. That seems healthy to me.
Canto: I agree completely. I’m not trying to say ‘all is capitalism’. There’s much more to life than that. The beauty of that story-telling and that affection for the land and its inhabitants and their ways is that it’s not a kind of master-race view. The Judeo-Christian view has been that all things, including all creatures, have been put here for our benefit. Of course modern Christianity has largely re-interpreted this as custodianship, which is an improvement, but I prefer the perspective that we’re all in this together, and we should look out for each other. Birds have to eat, and they like to eat fruit, and birds are fantastic creatures. They deserve our consideration.
Jacinta: Well that’s a nice note to end on. And what about the fossil fuel industry?
Canto: I think it’s had its day. It’s time to move beyond it.
Jacinta: Okay Canto, I rather hesitate to open up this subject, because I can’t see an end to it, but I want you to repeat here something you’ve said to me before about women and power, which goes to differences between men and women, an area subject to endless debate and contestation.
Canto: Ah well, I was considering how political power, in the world, is largely in the hands of men, and what the world would be like if the situation was reversed. It’s my humble opinion that the world would be less violent, more collaborative, and a lot more fun.
Jacinta: Well as a woman I’m obviously pleased to hear you say that, but we do try to look at evidence rather than personal opinion here, so what in the way of evidence leads you to this conclusion?
Canto: Well… where do we begin? Simone de Beauvoir famously wrote that women are made and not born, a highly contestable truism as it seems that women are actually wired differently from men, having less neurons but more connections between neurons, in toto and on average, so the very question of what it means to be a woman, or a man is one we’re unlikely to get to the bottom of, but I’d like to start with bonobos, always a favourite topic of mine. They appear to have diverged from chimpanzees only between a million and two million years ago, and they look very similar to chimps, which is likely why they weren’t identified as a separate species until the 1930s, and the differences seem to be far more social than anatomical. I mean, they share the same sexual dimorphism as chimps, and humans, and yet they’re essentially matriarchal, due it seems to social arrangements rather than individual size and strength. That gives me great hope for humans, especially now that physical size and strength are less relevant than ever as leadership qualities.
Jacinta: Ah, well now I get the fun part – you think a human matriarchal society will turn out to be a gigantic mutual wankfest. But what about civilisation? What about science and technology? Considering that women, regardless of culture or nationality, are more into astrology, fortune-telling, spiritualism, religion, naturopathy, and virtually every other pseudo-science and primitivism you care to mention, than men are.
Canto: Well, you’re talking about statistical differences, but you well know that there are many fine female astrophysicists, neurosurgeons, geneticists, experimental psychologists, whatever. You’re hardly the only female skeptic, even if they’re in a minority. And who knows what would happen if females were in a majority, with a history of being in a majority, with respect to leadership and power? Maybe you’d find then that it was men who were more into pseudo-science, statistically speaking.
Jacinta: True, and that brings me to a study analysed on the Skeptics’ Guide to the Universe recently. I had read, like you, that women, overall, had more white matter (the myelinated connections between neurons) than men – by a large factor, and that men had more grey matter, though this was concentrated around particular areas such as the amygdalae and the hypothalamus. However, in the study referred to, the researchers wanted to find if there were any categorical differences between male and female brains. They looked at 4 data sets of MRI and fMRI scans, checking out anatomical and connectional or networking differences, to make comparisons. According to SGU’s Steven Novella (a practising neurologist), the media over-simplified the findings as saying there were no differences, but in fact it was more interesting than that. Novella found this study to be essentially an exercise in examining how we categorise things (how do we define and categorise a disease, for example, or a planet, or a species). How we do so depends on a range of factors, and increasing knowledge, and better technology, helps us to develop parameters for categorising…
Canto: Though this also raises more problems… the more we know or learn, the more problematic our previous categories tend to become…
Jacinta: Anyway, in the case of female and male brains, the researchers distinguished between categorical differences and statistical differences. They used genitalia as a categorical difference. As Novella explains it, with genitalia we have a bimodal system, with male and female equipment…
Canto: I prefer to call it tackle…
Jacinta: And nothing really between. The vast majority of people, as subjects, can be placed in one category or another. Of course there are exceptions, but they are, always arguably, statistically insignificant. So, using this as a yardstick, the researchers wanted to know if there are categorical differences between male and female brains in the same way that there are categorical differences between male and female genitalia. One way to distinguish between categorical and statistical differences is whether, once you know which category an individual belongs to, that provides certainty about their particular traits. If it does, you have a categorical difference. So the researchers looked at about 40 different anatomical and functional aspects of the brain. They found that, generally speaking, there are statistical differences between males and females, in the size of various regions, the richness of the networks in various regions, but with a lot of overlap between the sexes; so it was statistical but not categorical. And the study didn’t look at causes of these differences, whether biological or social (we know that brains can be wired up through social conditioning to some degree). But they also did studies of individuals over the range of the 40 anatomical and functional features to determine how many were ‘typically’ male or female, or somewhere in between. One way to capture this was to ask – what percentage of people had 100% of their brain regions (those 40 features analysed) that were ‘typical’ of their sex? Among the 4 data sets, that percentage was 0 to 8%. So, very few men have ‘all-male’ brain regions, in terms of size and connections. Some 28% to 58% had a mixture of both.
Canto: So let me get this clear, the essential finding, according to Novella, was that though there were statistical differences in specific brain areas – and these are the differences described in ‘Do men and women have different brains?’ in How Stuff Works, from which the new ussr’s earlier post was largely derived – there is a lot of individual variation, which muddies the water rather a lot.
Jacinta: Yes, and I would say hopelessly, at least for those who want to think in stereotypes. As Novella puts it, people are mosaics of male and female traits. Another way of thinking about this, again put succinctly by Novella, is that we can’t assume that because a person is male – or female – we know what that person’s brain regions will be like. Statistical differences can’t automatically tell us about the brain region of any individual. There is no typically male or female brain in the way that there are typically male or female genitalia. And that is really interesting, and it might even mean that it’s illegitimate to say, ‘oh she’s female but she thinks like a man’, or ‘but she has a male brain’. There’s no male brain, or female brain, there are individual brains that are a product of all the influences, genetic, epigenetic, environmental, social, hormonal, psychological, whatever you can think of that influences brain activity and wiring.
Canto: And yet, and yet. Statistical differences do count for something don’t they? We still have the statistics showing that women are more into astrology and naturopathy than men…
Jacinta: Yes but what this study shows is that you can’t base this on some essentialist argument about female brains, and isn’t that a good thing?
Canto: Well, definitely, but then it works the other way. My argument that if women ruled we’d be so much better off can’t be based on anything essentialist either! Maybe being in power would turn their brains into something like the statistically typical male brain. My hopes are turning to dust…
Jacinto: No, no, don’t despair Canto. Consider the bonobos of the jungle…
Jacinta: Well Canto I’d like to get back to Einstein and space and time and the cosmos, just because it’s such a fascinating field to inhabit and explore.
Canto: Rather a big one.
Jacinta: I’ve read, or heard, that Einstein’s theory, or one of them, predicted black holes, though he didn’t necessarily think that such entities really existed, but now black holes are at the centre of everything, it seems.
Canto: Including our own galaxy, and most others.
Jacinta: Yes, and there appears to be a correlation between the mass of these supermassive black holes at the centres of galaxies and the mass of the galaxies themselves, indicating that they appear to be the generators of galaxies. Can you expand on that?
Canto: Well the universe seems to be able to expand on that better than I can, but I’ll try. Black holes were first so named in the 1960s, but Einstein’s theory of general relativity recast gravity as a distortion of space and time rather than as a Newtonian force, with the distortion being caused by massive objects. The greater the mass, the greater the distortion, or the ‘geodetic effect’, as it’s called. The more massive a particular object, given a fixed radius, the greater is the velocity required for an orbiting object to escape its orbit, what we call its escape velocity. That escape velocity will of course, approacher closer and closer to the speed of light, as the object being orbited becomes more massive. So what happens when it reaches the speed of light? Then there’s no escape, and that’s where we enter black hole territory.
Jacinta: So, let me get this. Einstein’s theory is about distortions of space-time (and I’m not going to pretend that I understand this), or geodetic effects, and so it has to account for extreme geodetic effects, where the distortion is so great that nothing, not even light, can escape, and everything kind of gets sucked in… But how do these massive, or super-massive objects come into being, and won’t they eventually swallow all matter, so that all is just one ginormous black hole?
Canto: Okay I don’t really get this either but shortly after Einstein published his theory it was worked out by an ingenious astrophysicist, Karl Schwarzschild – as a result of sorting out Einstein’s complex field equations – that if matter is severely compressed it will have weird effects on gravity and energy. I was talking a minute ago about increasing the mass, but think instead of decreasing the radius while maintaining the mass as a constant…
Jacinta: The same effect?
Canto: Well, maybe, but you’ll again reach a point where there’s zero escape, so to speak. In fact, what you have is a singularity. Nothing can escape from the object’s surface, whether matter or radiation, but also you’ll have a kind of internal collapse, in which the forces that keep atoms and sub-atomic particles apart are overcome. It collapses into an infinitesimal point – a singularity. It was Schwarzschild too who described the ‘event horizon’, and provided a formula for it.
Jacinta: That’s a kind of boundary layer, isn’t it? A point of no return?
Canto: Yes, a spherical boundary that sort of defines the black hole.
Jacinta: So why haven’t I heard of this Schwarzschild guy?
Canto: He died in 1916, shortly after writing a paper which solved Einstein’s equations and considered the idea of ‘point mass’ – what we today would call a singularity. But both he and Einstein, together with anyone else in the know, would’ve considered this stuff entirely theoretical. It has only become significant, and very significant, in the last few decades.
Jacinta: And doesnt this pose a problem for Einstein’s theory? I recall reading that this issue of ‘point mass’, or a situation where gravity is kind of absolute, like with black holes and the big bang, or the ‘pre-big bang’ if that makes sense, is where everything breaks down, because it seems to bring in the mathematical impossibility of infinity, something that just can’t be dealt with mathematically. And Einstein wasn’t worried about it in his time because black holes were purely theoretical, and the universe was thought to be constant, not expanding or contracting, just there.
Canto: Well I’ve read – and I dont know if it’s true – that Einstein believed, at least for a time, that black holes couldn’t actually exist because of an upper limit imposed on the gravitational energy any mass can produce – preventing any kind of ‘infinity’ or singularity.
Jacinta: Well if that’s true he was surely wrong, as the existence of black holes has been thoroughly confirmed, as has the big bang, right?
Canto: Well of course knowledge was building about that in Einstein’s lifetime, as Edwin Hubble and others provided conclusive evidence that the universe was expanding in 1929, so if this expansion was uniform and extended back in time, it points to an early much-contracted universe, and ultimately a singularity. And in fact Einstein’s general relativity equations were telling him that the universe wasn’t static, but he chose to ignore them, apparently being influenced by the overwhelming thinking of the time – this was 1917 – and he introduced his infamous or famous cosmological constant, aka lambda.
Jacinta: And of course 1917 was an early day in the history of modern astronomy, we hardly knew anything beyond our own galaxy.
Canto: Or within it. One of the great astrophysicists of the era, Sir Arthur Eddington, believed at the time that the sun was at the centre of the universe, while admitting his calculations were ‘subject to large uncertainties’.
Jacinta: Reminds me of Lord Kelvin on the age of the Earth only a few generations before.
Canto: Yes, how quickly our best speculations can become obsolete, but that’s one of the thrills of science. And it’s worth noting that the work of Hubble and others on the expansion of the universe depended entirely on improved technology, namely the 100-inch Hooker telescope at Mount Wilson, California.
Jacinta: Just as the age of the Earth problem was solved through radiometric dating, which depended on all the early twentieth century work on molecular structure and isotopes and such.
Canto: Right, but now this lambda (λ) – which Einstein saw as a description of some binding force in gravity to counteract the expansion predicted by his equations – is very much back in the astrophysical frame. The surprising discovery made in 1998 that the universe’s expansion is accelerating rather than slowing has, for reasons I can’t possibly explain, brought Einstein’s lambda in from the cold as an explanatory factor in that discovery, which is also somehow linked to dark energy.
Jacinta: So his concept, which he simply invented as a ‘fix-it’ sort of thing, might’ve had more utility than he knew?
Canto: Well the argument goes, among some, that Einstein was a scientist of such uncanny insight that even his mistakes have proved more fruitful than others’ discoveries. Maybe that’s hero worship, maybe not.
Jacinta: So how does lambda relate to dark energy, and how does dark energy relate to dark matter, if you please?
Canto: Well the standard model of cosmology (which is currently under great pressure, but let’s leave that aside) has been unsuccessful in trying to iron out inconsistent observations and finding with regard to the energy density of the universe, and so dark energy and what they call cold dark matter (CDM) have been posited as intellectual placeholders, so to speak, to make the observations and equations come out right.
Jacinta: Sounds a bit dodgy.
Canto: Well, time will tell how dodgy it is but I don’t think anyone’s trying to be dodgy, there’s a great deal of intense calculation and measurement involved, with so many astrophysicists looking at the issue from many angles and with different methods. Anyway, to quickly summarise CDM and dark energy, they together make up some 96% of the mass-energy density of our universe according to the most currently accepted calculations, with dark energy accounting for some 69% and CDM accounting for about 27%.
Jacinta: Duhh, that does sound like a headachey problem for the standard model. I mean, I know I’m only a dilettanty lay-person, but a model of universal mass-energy that only accounts for about 4% of the stuff, that doesn’t sound like much of a model.
Canto: Well I can assure they’re working on it…
Jacinta: Or working to replace it.
Canto: That too, but let me try to explain the difference between CDM and dark energy. Dark energy is associated with lambda, because it’s the ‘missing energy’ that accounts for the expansion of the universe, against the binding effects of gravity. As it happens, Einstein’s cosmological constant pretty well perfectly counters this expansive energy, so that if he hadn’t added it to his equations he would’ve been found to have predicted an expanding universe decades before this was confirmed by observation. That’s why it was only in the thirties that he came to regret what he called the greatest mistake of his career. Cold dark matter, on the other hand, has been introduced to account for a range of gravitational effects which require lots more matter than we find in the observed (rather than observable) universe. These effects include the flat shapes of galaxies, gravitational lensing and the tight clustering of galaxies. It’s described as cold because its velocity is considerably less than light-speed.
Jacinta: Okay, so far so bad, but let’s get back to black holes. Why are they so central?
Canto: Well, that’s perhaps the story of supermassive black holes in particular, but I suppose I should try to tell the story of how astronomers found black holes to be real. As I’ve said, the term was first used in the sixties, 1967 to be precise, by John Wheeler, at a time when their actual existence was being considered increasingly likely, and the first more or less confirmed discovery was made in 1971 with Cygnus x-1. You can read all about it here. It’s very much a story of developing technology leading to increasingly precise observational data, largely in the detecting and measuring of X-ray emissions, stuff that was undetectable to us with just optical instruments.
Jacinta: Okay, go no further, I accept that there’s been a lot of data from a variety of sources that have pretty well thoroughly confirmed their existence, but what about these supermassive black holes? Could they actually be the creators of matter in the galaxies they’re central to? That’s what I’ve heard, but my reception was likely faulty.
Canto: Well astrophysicists have been struggling with the question of this relationship – there clearly is a relationship between supermassive black holes and their galaxies, but which came first? Now supermassive black holes can vary a lot – our own ‘local’ one is about 4 million solar masses, but we’ve discovered some with billions of solar masses. But it was found almost a decade ago that there is correlation between the mass of these beasties and the mass of the inner part of the galaxies that host them – what they call the galactic bulge. The ratio is always about 1 to 700. Obviously this is highly suggestive, but it requires more research. There are some very interesting examples of active super-feeding black holes emitting vast amounts of energy and radiation, which is both destructive and productive in a sense, creating an active galaxy. Our own Milky Way, or the black hole at its centre, is currently quiescent, which is just as well.
Jacinta: You mean if it starts suddenly feeding, we’re all gonna die?
Canto: No probably not, the hole’s effects are quite localised, relatively speaking, and we’re a long way from the centre.
Jacinta: Okay thanks for that, that’s about as much about black holes as I can stand for now.
Canto: Well I’m hoping that in some future posts we can focus on the technology, the ground-based and space-based telescopes and instruments like Hubble and Kepler and James Webb and so many others that have been enhancing our knowledge of black holes, other galaxies, exoplanets, all the stuff that makes astrophysics so rewarding these days.
Jacinta: You’re never out of work if you’re an astrophysicist nowadays, so I’ve heard. Halcyon days.
If we don’t know what’s in them, it’s very difficult to predict the interactions, … that’s obviously of great concern if they are been given to children, or pregnant women, the potential outcomes there are very serious.
Murdoch University biochemist Dr Garth Maker
There’s nothing particularly positive to say about naturopathic treatments generally – some of which (homeopathy, reflexology, iridology, acupuncture and cupping, to name a few) are not so much ‘natural’, whatever that means, as examples of comprehensively failed hypotheses (hardly worthy of the name). But so-called traditional Chinese medicine is on the lowest rung, considering how much damage it has done, not only to humans but to other species that have been horribly exploited in its name. The latest damning finding about what is actually contained in many of these unregulated pills will probably barely create a ripple amongst the anti-science crowd, but nevertheless it needs to get as much publicity as possible. You never know, maybe someone, somewhere will take notice (and we’re fighting a real battle here, because if you go online to find out about TCM, you’ll find the whole internet disturbingly skewed towards the positive). Please, if only for the sake of the children exposed to this crap by ignorant parents, let’s do something about this. It’s an effing outrage.