Posts Tagged ‘evolution’
CARE and women’s empowerment
We have an abundance of rape and violence against women in this country and on this Earth, though it’s almost never treated as a civil rights or human rights issue, or a crisis, or even a pattern. Violence doesn’t have a race, a class, a religion or a nationality, but it does have a gender.
Rebecca Solnit, author and historian
Canto: So the CARE organisation, an NGO with a long history, is perhaps best known to us here due to our former PM Malcolm Fraser becoming the founder of CARE Australia in 1987, and the president of CARE international from 1990 to 1995. It’s one of the oldest humanitarian aid organisations, with its origins in the forties, in that post-war period when international co-operation and healing became something of an obsession. But did you know that in recent times it has directed its focus on the empowerment of women in disadvantaged circumstances?
Jacinta: Yes, this is something we’ve been discovering only recently, and if you go to the CARE website right now you’ll find the leading article there is about women fleeing Syria, often with children, and about the increasing number of female-headed families among Syrian refugees in Jordan and elsewhere.
Canto: Well, that’s illustrative, and as you know I’ve just read Melvin Konner’s book, Women after all: sex, evolution and the end of male supremacy, and it has a few pages on CARE and how it has kind of renewed itself in recent times by focusing on female disadvantage, and I think that’s a damn good idea.
Jacinta: Yes, not exclusively of course, but it has been focusing on education and empowerment – those things go naturally together of course – which is more of an issue for women in countries like India and many African countries.
Canto: Oh yeah in many countries, wherever you have extreme male dominance you have women reduced to drudgery, virtual slavery, if not actual slavery, women forced into marriage at an early age, an acceptance of rape within marriage, and of course women and girls deprived of whatever paltry education they have in these benighted regions. And these are the most violent and backward regions in the world, but I suppose we’ve harped on that enough already.
Jacinta: So what specifically is CARE doing for women?
Canto: Well its rebranding, as Konner describes it, began nearly a decade ago with a campaign called ‘I am Powerful’ developed by Helene Gayle, then CEO of CARE USA. It was all about knowledge being power and education being key, and this was focused on in a lot of problem regions, in India, Bangladesh, Yemen…
Jacinta: I read that, in India, of the children not attending school, 80% are female. One of the worst records anywhere, but of course, the percentage of girls not being educated is always higher than boys wherever you look.
Canto: Even in Australia?
Jacinta: Well, I’m guessing, but we’ve not quite reached gender equality, and then there are migrants coming from heavily patriarchal societies…
Canto: Anyway the research they did showed the knock-on effects of education for women and girls. Educated girls postpone motherhood, have fewer kids, healthier kids, better educated kids, and this transfers to the next generation and the next in a multiplier effect.
Jacinta: And educated women earn more, suffer less abuse, are healthier…
Canto: So they’ve done great work in developing schools in Benin and Sudan and other trouble spots, places where educated women were a novelty. But it’s not just education, they’ve been providing safe havens for women against male violence within refugee camps in Kenya and Sri Lanka where they had such brutal suppression of the Tamils. And they’ve been involved in microfinancing, along with other NGOs and banks. Because over the decades they’ve found that loans to women are more effective than loans to men.
Jacinta: Hmmm, I wonder why that would be.
Canto: Well, some have disputed it, but it might be that because women are generally more collaborative and group-oriented, social pressure between women ensures that they put the loans to better use, repay them more promptly and so on. CARE is also combining microloans with training in health, governance, human rights and such. This raises consciousness on the importance of education and health, and this is indicated in increased household expenditure in these areas. It’s been noted that microfinance-only programs tend to be more abused, often because the women get leaned on by male relatives.
Jacinta: Okay, so I think you’re right, we need to get rid of men. Gene editing, with this new CRISPR Cas-9 technology and further developments, should make it all straightforwardly possible soon enough. In time we’ll be able to edit the genes of embryos to make them all female. Or maybe we’ll keep about 10% of them as males for reproductive purposes, and as fun toys and slaves around the house. Forget the bloody moslem brotherhood, I’m only interested in the moslem sisterhood, and forget mateship, which emerged supposedly out of the ‘Great’ bloody War, and fuck ‘we band of brothers’, which came from Shakespeare’s bloody Henry V, the battle of bloody AgitpropCourt, with Harry’s band of bros splattering the Frenchy band of bros for larks and sparks. Yep it’s time.
Canto: Well thanks for that. We’ll talk again, women willing.
beyond feminism – towards a female supremacist society
Canto: I’ve decided to declare myself as a female supremacist.
Jacinta: Really? I thought you had nothing to declare but your genius. So you’ve come out at last?
Canto: Well it’s not as if I’ve been stifled in the closet for years. I’ve rarely thought about it before. I’ve always considered myself a feminist, but recently we’ve been looking at female-male differences, and it’s been making me feel we need more than just equality between the sexes.
Jacinta: You’ve got a hankering for that bonobo world, haven’t you? Females ganging up on you and soothing your aggressive macho emotions with a bit of sexual fourplay.
Canto: Well, yes and no. I first learned about bonobo society almost twenty years ago, and of course it excited me as a model, but then the complexity of human societies with all their cultural overlays made me feel I was naive to imagine a non-human society, without even its own language, could teach us how to improve our own. And the sex stuff in particular – well, that really got me in, but then it seemed too good to hope for. Too much self-serving wishful thinking, to model our society on a bunch of oversexed, indolent banana-eaters.
Jacinta: Do they have bananas in the Congo?
Canto: Absolutely. They have a town there on the Congo River, called Banana.
Jacinta: Oh wow, sounds like heaven. I love bananas. Let’s go there.
Canto: Anyway, now I’m thinking that a female-supremacist society is what we need today, though not necessarily based on bonobos….
Jacinta: That’s disappointing. I think it should be based on bonobos. Bonobos with language and technology and sophisticated theories about life, the universe and everything. Why not?
Canto: Well then they wouldn’t be bonobos. But do you want to hear my reasons for promoting female supremacy?
Jacinta: I probably know them already. Look at the male supremacist societies and cultures in the world – in Africa, in India, in the Middle East. They’re the most violent and brutish societies. We can’t compare them to female supremacist societies because there aren’t any, but we can look at societies where discrimination against women is least rampant, and those are today’s most advanced societies. It might follow that they’ll become even more enlightened and advanced if the percentage of female leaders, in business, politics and science, rises from whatever it is today – say 10% – to, say 90%.
Canto: Yes, well you’re pretty much on the money. It’s not just broader societies, it’s workplaces, it’s schools, it’s corporations. The more women are involved, especially in leadership roles, the more collaborative these places become. Of course I don’t deny female violence, in schools and at home, against children and partners and in many other situations, but on average in every society and every situation women are less violent and aggressive than men. In fact, all the evidence points to a female-supremacist society being an obvious solution for a future that needs to be more co-operative and nurturing.
Jacinta: So how are you going to bring about the female-supremacist revolution?
Canto: Not revolution, that’s just macho wankery. I’m talking about social evolution, and it’s already happening, though of course I’d like to see it speeded up. We’ll look at how things are changing and what we can hope for in some later posts. But the signs are good. The feminisation of our societies must continue, on a global level!
bonobos and us – lessons to be learnt
Let’s be sexy about this
Bonobos separated from chimps maybe less than a million years ago, according to some pundits. We haven’t yet been able to determine a more precise date for the split. So which species has changed more? Have chimps become more aggressive or have bonobos become more caring? Is there any way of finding out?
It’s not just about genes its about their expression. It will take some time to work all that out. Brain studies too will help, as we move towards scanning and exploring brains more effectively and less invasively.
But surely we seek not just to understand the bonobo world but to change our own. Who wouldn’t want a world that was less violent, less exclusionary in terms of sex, more caring and sharing, without any loss of the dynamism and questing that has taken us to to the very brink of iphone7?
That last remark will date very quickly… Nah, I’ll leave it in.
So we can learn lessons, and of course we’re already on that path. Advanced societies, if that’s not too presumptuous a term, are less patriarchal than they’ve ever been, without losing any of their dynamism. On the contrary, it can easily be seen that the most male-supremacist societies in the world are also the most violent, the most repressive and the most backward. Some of those societies, as we know, have their backwardness masked by the fact that they have a commodity, oil, that the world is still addicted to, which has made the society so rich that their citizens don’t even have to pay tax. The rest of the world is supporting tyrannical regimes, which won’t change as long as they feel well-fed and secure. Not that I’d wish starvation and insecurity on anyone, but as Roland Barthes once said at one of his packed lectures, the people standing at the back who can’t hear properly and have sore feet must be wondering why they’re here.
Maybe a bit of discomfort, in the form of completely shifting away from fossil fuels for our energy needs haha, might bring certain Middle Eastern countries to a more serious questioning of their patriarchal delusions? Without their currently-valuable resource, they might wake to the fact that they need to become smarter. The women in those countries, so effective on occasion in forming coalitions to defend their inferior place in society, might be encouraged to use their collective power in more diverse ways. That could be how things socially evolve there.
Meanwhile in the west, the lesson of the bonobos would seem to be coalitions and sex. We’ve certainly arrived at an era where sexual dimorphism is irrelevant, except where women are isolated, for example in domestic situations. The same isolation also poses a threat to children. The bonobo example of coalitions and togetherness and sharing of responsibilities, and sexual favours (something we’re a long way from emulating, with our jealousies and petty rivalries) should be the way forward for us. Hopefully the future will see a further erosion of the nuclear family and a greater diversity of child-rearing environments, where single-parent families are far less isolated than they are today, and males want to help and support and teach children because they are children, not because they are their children…
bonobo society, or how to dominate males when you’re smaller
A BONOBO FAMILY IN A FOREST CLEARING IN WAMBA, ZAIRE.
CREDIT: 1996 FRANS LANTING
Bonobo society has been closely observed both in captivity and, with much greater difficulty, in the wild, and it’s worth comparing it to that of their close relatives, chimps. It’s clear that, though aggression does exist in bonobo society, it isn’t anywhere near as prevalent as in chimps. This is obviously related to the use, mentioned previously, of sex to reduce tension and aggression in situations which would normally lead to competitive activity. It’s the ‘make love not war’ social system that has caught the attention of many beyond ethological researchers.
Now, it’s clear that aggression in all primate societies comes predominantly from males. Looking at human societies, the statistics are universal. There is no human society on earth where the homicide and/or assault statistics are dominated by females as perpetrators. Up until very recently it was males who went to war, and today it’s overwhelmingly males who joing gangs, go hoon driving or join terrorist cells, just as in earlier times it was men who journeyed off to the adventure of the crusades or joined Boney’s army to devastate Europe. As Melvin Konner convincingly argues, this strongly indicates a biological or genetic basis for male aggression. Much of it seems to be about the expression in males of androgens, the male sex hormones. Now with the way we’re going today in genetics and biochemistry we may in the future be able to tweak the production of androgens to offer a biological solution to male violence – which is already in decline in developed countries. However, their are other solutions, and Bonobo society represents one.
Bonobo society is very close-knit. Male bonobos develop close lifelong ties with their mothers. There’s no relationship with the father, who’s unknown, as the females engage in sex with multiple partners more or less indiscriminately. Of course males will compete with other males for sexual partners, but even this aggression is damped down by sexual relations between males. It’s as if the button has been found to switch off escalating aggression, and that button is connected to the genitals. It would be intriguing to discover what’s going on in the brain, with neurotransmitters and hormones, during this rise and fall of aggressive emotions.
Sex doesn’t just reduce aggression though. It virtually creates the bonobo social structure. As with chimps, bonobos have a fission-fusion society, breaking off into smaller ‘unit’ groups for hunting and foraging in the forest and coming together in larger groups at other times. Individual associations, apart from the mother-offspring dependency, are casual and changeable. However, the larger group, or community, has its limit, and keeps itself separate from other bonobo communities. Another feature of bonobo society is that females emigrate from their birth groups at around 8 years of age, moving to group of virtual strangers, where they have to work to build relationships, particularly with older females. The female-female bond is a central feature of bonobo society and these bonds become much stronger than in chimp society, in spite of the fact that these females, having come from other groups, are less genetically related than the males. This bond is cemented by sex, which creates loosely hierarchical coalitions, with one female dominating, mostly through reproductive success – especially in the production of males. Sisterhood is powerful, and it’s not necessarily about genetics. It’s a great lesson for our society, if we can get over the idea, so prevalent but hopefully fading, that we’re unique in a more unique way than any other species is unique, that we’re civilized, and that we have little or nothing to learn from our primate cousins.
And there’s so much more to learn, as we’ll see.
Resources:
http://pin.primate.wisc.edu/factsheets/entry/bonobo/behav
http://www.scientificamerican.com/article/bonobo-sex-and-society-2006-06/
M Konner, Women after all: sex, evolution and the end of male supremacy
bonobo society, sex and females
sexual dimorphism – a difference on average, but massive individual variation
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.
bonobo relations – more than just sex
matriarchy – surely it couldn’t be worse than patriarchy?
In one of the international English classes I occasionally teach, we have an opportunity for debate. Here’s a debate topic I’ve thought up but haven’t yet tried out: If 90 to 99% of the world’s business and political leaders were female, instead of male as they are today, would the world be a better place to live in?
It’s not a question that’ll find a definitive answer in the foreseeable future, but my strong view is that the world would be better.
Why? I’m not entirely convinced that women are the gentler sex, and I’m very wary of succumbing to a facile view of women as inherently more calm, co-operative and conciliatory, but I think that on balance, or statistically, they’re more risk averse, less impulsive, and, yes, more group-oriented. Whether such tendencies are natural or nurtured, I’m not at all sure. It’s a question I intend to investigate.
So to stimulate myself in pursuing the subject of patriarchy and its obverse I’m reading Women after all: sex, evolution and the end of male supremacy, a rather optimistically-titled book by an American doctor and teacher, Melvin Konner. It’s one of many sources of information I hope to access in the future. It argues that there are fundamental differences between males and females, and that females are the superior gender. I’m not sure about the ‘fundamentals’, or categorical differences, but I agree that the current differences can and probably should be interpreted in terms of female superiority. Certainly, given the needs and responsibilities of humanity in this time, woman appear to have more of the goods than males for facing the future. After all, if we look back at the last 6000 or so years of human history, it’s dominated by male warfare, and if we look at today’s most violent and brutish cultures, they’re clearly the most patriarchal.
Of course if you believe that women and men are fundamentally different, as Konner does, then it becomes straightforward to argue for women being in control, because it’s highly unlikely, indeed impossible I’d say, that these fundamentally different genders are precisely equal in value. And given the devastation and suffering that men have caused over the period of what we call ‘human civilisation’, and given that women are the (mostly) loving mothers of all of us, it seems obvious that, if there is a fundamental difference, women’s qualities are of more value.
On the other hand if you’re a bit more skeptical about fundamental differences, as I am, and you suspect that the idea that ‘absolute power corrupts absolutely’ is as applicable to women as it is to men, you’ll feel rather more uncertain about a profoundly matriarchal society. And yet…
I draw some inspiration for the benefits of matriarchy from the closest living relatives of homo sapiens. There are two of them. The line that led to us split off from the line that led to chimps and bonobos around 6 million years ago. Chimps and bonobos split from their common ancestor much more recently, perhaps only a little over a million years ago, so they’re both equally related to us. Chimps and bonobos look very very alike, which is presumably why bonobos were only recognised as a separate species in the 1930s – quite extraordinary for such a physically large animal. But of course bonobo and chimp societies are very very different, and vive la différence. I’ve written about bonobo society before, here and here, but can’t get enough of a good thing, so I’ll look more closely at that society in the next few posts.
I think I’d rather be a bonobo
Abiogenesis – LUCA, gradients, amino acids, chemical evolution, ATP and the RNA world
Jacinta: So now we’re thinking of the Earth 4 billion years BP, with an atmosphere we’re not quite sure of, and we want to explore the what and when of the first life forms. Haven’t we talked about this before?
Canto: Yeah we talked about the RNA world and viroids and abiogenesis, the gap between chemistry and biology, inter alia. This time we’re going to look more closely at the hunt for the earliest living things, and the environments they might’ve lived in.
Jacinta: And it started with one, it must have. LUA, or LUCA, the last universal common ancestor. Or the first, after a number of not-quite LUCAs, failed or only partially successful attempts. And finding LUCA would be much tougher than finding a viroid in a haystack, because you’re searching through an immensity of space and time.
Canto: But we’re much closer to finding it than in the past because we know so much more about what is common to all life forms.
Jacinta: Yes so are we looking definitely at the first DNA-based life form or are we probing the RNA world again?
Canto: I think we’ll set aside the world of viroids and viruses for now, because we want to look at the ancestor of all independently-existing life forms, and they’re all DNA-based. And we also know that LUCA used ATP. So now I’m going to quote from an essay by Michael Le Page in the volume of the New Scientist Collection called ‘Origin, Evolution, Extinction’:
How did LUCA make its ATP? Anyone designing life from scratch would probably make ATP using chemical reactions inside the cell. But that’s not how it is done. Instead energy from food or sunlight is used to power a protein ‘pump’ that shunts hydrogen ions – protons – out of the cell. This creates a difference in proton concentration, or a gradient, across the cell membrane. Protons then flow back into the cell through another protein embedded in the membrane, which uses the energy to produce ATP.
Jacinta: You understand that?
Canto: Sort of.
Jacinta: ‘Energy from food or sunlight is used..’ that’s a bit of a leap. What food? The food we eat is organic, made from living or formerly living stuff, but LUCA is the first living thing, its food must be purely chemical, not biological.
Canto: Of course, not a problem. I believe the microbes at hydrothermal vents live largely on hydrogen sulphide, and of course sunlight is energy for photosynthesising oganisms such as cyanobacteria.
Jacinta: Okay, so your simplest living organisms, or the simplest ones we know, get their energy by chemosynthesis, or photosynthesis. Its energy, or fuel, not food.
Canto: Semantics.
Jacinta: But there are other problems with this quote re abiogenesis. For example, it’s talking about pre-existent cells and cell membranes. So assuming that cells had to precede ATP.
Canto: No, he’s telling us how cells make ATP today. So we have to find, or synthesise, all the essential ingredients that make up the most basic life forms that we know – cell membranes, proteins, ATP and the like. And people are working towards this.
Jacinta: Yes and first of all they created these ‘building blocks of life’, as they always like to call them, amino acids, in the Miller-Urey experiments, since replicated many times over, but what exactly are nucleic acids? Are they the same things as nucleic acids?
Canto: Amino acids are about the simplest forms of organic compounds. It’s probably better to call them the building blocks of proteins. There are many different kinds, but generally each contain amine and carboxyl groups, that’s -NH2 and -COOH, together with a side chain, called an R group, which determines the type of amino acid. There’s a whole complicated lot of them and you could easily spend a whole lifetime fruitfully studying them. They’re important in cell structure and transport, all sorts of things. We’ve not only been able to create amino acids, but to combine them together into longer peptide chains. And we’ve also found large quantities of amino acids in meteorites such as the Murchison – as well as simple sugars and nitrogenous bases. In fact I think we’re gradually firming up the life-came from-space hypothesis.
Jacinta: But amino acids and proteins aren’t living entities, no matter how significant they are to living entities. We’ve never found living entities in space or beyond Earth. Your quote above suggests some of what we need. A boundary between outside and inside, a lipid or phospho-lipid boundary as I’ve heard it called, which must be semi-permeable to allow chemicals in on a very selective basis, as food or fuel.
Canto: I believe fatty acids formed the first membranes, not phospho-lipids. That’s important because we’ve found that fatty acids, which are made up of carbon, hydrogen and oxygen atoms joined together in a regular way, aren’t just built inside cells. There’s a very interesting video called What is Chemical Evolution?, produced by the Center for Chemical Evolution in the USA, that tells about this. Experimenters have heated up carbon monoxide and hydrogen along with many minerals common in the Earth’s crust and produced various carbon compounds including fatty acids. Obviously this could have and can still happen naturally on Earth, for example in the hot regions maybe below or certainly within the crust. It’s been found that large concentrations of fatty acids aggregate in warm water, creating a stable, ball-like configuration. This has to do with the attraction between the oxygen-carrying heads of fatty acids and the water molecules, and the repulsion of the carbon-carrying tails. The tails are forced together into a ball due to this repulsion, as the video shows.
fatty acids, with hydrophobic and hydrophilic ends, aggregating in solution
Jacinta: Yes it’s an intriguing video, and I’m almost feeling converted, especially as it goes further than aggregation due to these essentially electrical forces, but tries to find ways in which chemical structures evolve, so it tries to create a bridge between one type of evolution and another – the natural-selection type of evolution that operates upon reproducing organisms via mutation and selection, and the type of evolution that builds more complex and varied chemical structures from simpler compounds.
Canto: Yes but it’s not just the video that’s doing it, it’s the whole discipline or sub-branch of science called chemical evolution.
Jacinta: That’s right, it’s opening a window into that grey area between life and non-life and showing there’s a kind of space in our knowledge there that it would be exciting to try and fill, through observation and experimentation and testable hypotheses and the like. So the video, or the discipline, suggests that in chemical evolution, the highly complex process of reproduction through mitosis in eukaryotic cells or binary fission in prokaryotes is replaced by repetitive production, a simpler process that only takes place under certain limited conditions.
Canto: So under the right conditions the balls of fatty acids grow in number and themselves accumulate to form skins, and further forces – I think they’re hydrostatic forces – can cause the edges of these skins to fuse together to create ‘containers’, like vesicles inside cells.
Jacinta: So we’re talking about the creation of membranes, impermeable or semi-permeable, that can provide a safe haven for, whatever…
Canto: Yes, and at the end of the video, other self-assembling systems, such as proto-RNA, are intriguingly mentioned, so we might want to find out what’s known about that.
Jacinta: I think we’ll be doing a lot of reading and posting on this subject. I find it really fascinating. These limited conditions I mentioned – limited on today’s Earth surface, but not so much four billion years ago, include a reducing atmosphere lacking in free oxygen, and high temperatures, as well as a gradient – both a temperature gradient and a sort of molecular or chemical gradient, from more reducing to more oxidising you might say. These conditions exist today at hydrothermal vents, where archaebacteria are found, so researchers are naturally very interested in such environments, and in trying to replicate or simulate them.
Canto: And they’re interested in the boundary between chemical and biological evolution, and reproduction. There are so many interesting lines of inquiry, with RNA, with cell membranes….
Jacinta: Researchers are particularly interested in alkaline thermal vents, where alkaline fluids well up from beneath the sea floor at high temperatures. When this fluid hits the ocean water, minerals precipitate out and gradually create porous chimneys up to 60 metres high. They would’ve been rich in iron and sulphide, good for catalysing complex organic reactions, according to Le Page. The temperature gradients created would’ve favoured organic compounds and would’ve likely encouraged the building of complexity, so they may have been the sites in which the RNA world began, if it ever did.
a hydrothermal vent off the coast of New Zealand. Image from NOAA
Canto: So I think we should pursue this further. There are a lot of researchers homing in on this area, so I suspect further progress will be made soon.
Jacinta: Yes, we need to explore the exploitation of proton gradients, the development of proton pumps and the production of ATP, leaky membranes and a whole lot of other fun stuff.
Canto: I think we need to get our heads around ATP and its production too, because that looks pretty damn complex.
Jacinta: Next time maybe.
clever Charlie Darwin
A photo taken by me! King Charles seated in state in the Musuem of Natural History, London. It was a thrill to be granted an audience
I recently decided to reread Darwin’s Origin of Species, which was really reading it for the first time as my first reading was pretty cursory, and I could barely follow the wealth of particular knowledge he used for cumulative effect to adduce his theory. This time I’ve been doing a closer reading, and becoming increasingly impressed, and I’ve only read the first chapter, ‘Variation under Domestication’.
Darwin’s argument here of course is that domesticated horses, dogs, birds and plants have been artificially selected over long periods of time, and often unconsciously, to suit human needs and tastes. This might seem screamingly obvious today, and to a degree it was recognised in Darwin’s time, but because of an inability to take the long view, and also because of the then-prevalent paradigm of the fixity of species, breeders and nurserymen tended to under-estimate their own cumulative powers, and to claim, for example, that dogs and pigeons had always come in many varieties. Even Darwin was uncertain, and was willing to concede – writing of course before the advent of Mendelian genetics, never mind the revolution wrought by the identification and analysis of DNA as the molecule of inheritance – that in some cases the breeders might be right:
In the case of most of our anciently domesticated animals and plants, I do not think it is possible to come to any definite conclusion, whether they have descended from one or several species.
He was even prepared to concede that it was ‘highly probable that our domestic dogs have descended from several wild species’, while at the same time arguing that the breeding of dogs, in Egypt, other parts of Africa and Australia (where, in his Beagle travels, he observed dingoes, which he may have seen as semi-domesticated by the Aborigines) extended back far further in time than most people suspected. We now know that Darwin’s concession here was ‘premature’. The latest research strongly suggests that our domesticated dogs trace their ancestry to a group of European wolves dating from 19,000 to 32,000 years ago, and probably now extinct. That’s a time-frame Darwin would’ve baulked at, and it’s both funny and kind of tragic that this is something I’ve ‘discovered’ after 30 seconds of selective internet searching. There’s no doubt, though that Darwin’s bold but always informed speculations were heading in the right direction.
Particularly informed – and bold – were his speculations about pigeons. This is hardly surprising as he spent several years studying and breeding them himself. Interestingly, he started doing so because he’d become convinced that all the fancy pigeons then on show were most likely derived from one common species, the rock pigeon or rock dove (Columba livia), a view already held by some naturalists but few breeders. He devotes several pages in Chapter 1 to arguing his case, for example pointing out that the ‘several distinct species’ argued for by breeders can be crossed with complete success, that’s to say with no signs of sterility or more than usually defective offspring.
So, as with dogs, I decided to look up what the latest research was on the ancestry of English carriers, short-faced tumblers, runts, fantails, common tumblers, barbs, pouters, trumpeters and laughers, to name some of the pigeons Darwin mentions in the chapter, and was excited to find that a piece of research published as recently as 2013 has confirmed Darwin’s hypothesis. Cheaper and faster genome sequencing technologies have enabled researchers to sequence the genomes of many wild and domesticated birds, and they’ve found that all of the latter are clearly closer to C livia than to any other wild species. It only took just over 150 years for Darwin to be proven correct.
Close reading like this really does reap some fun rewards, and I’ll finish with two more examples. Darwin wrote of how in the world of breeding, quite a drastic change can be brought about in one breeding step, as in the case of the fuller’s teasel with its hooks. He goes on:
So it has probably been with the turnspit dog; and this is known to have been the case with the ancon sheep.
Not knowing wtf he was talking about, I irritatedly decided to look up these unknown creatures. The turnspit dog is a now-extinct breed, bred specifically from around the 16th century to provide the dogpower to turn meat on a spit, the only conceivable way of cooking large joints of meat in your average fancy household for a couple of centuries. The dog, or dogs, because the system worked better if you had two of them engaged in shift work, turned a wheel by running inside it, rat-like, until the meat was cooked. They were known to be long-bodied and short-legged, but details of how they were bred aren’t known, as they were apparently beneath scholarly consideration. They certainly weren’t seen as cuddly pets – if you treat creatures as slaves it heightens your contempt for then (cf Aristotle) – and they were even taken to church as foot-warmers. They’d disappeared entirely by the end of the 19th century.
It’s a dog’s life?
The ancon sheep was a short-legged type, apparently bred from a single individual in the USA in the late nineteenth century, its short legs having the singular advantage, to some, of curtailing its hopes of freedom by jumping the fence. The term ‘ancon’ has since been used by breeding researchers to describe strains of creatures arising from an individual with the same phenotype.
The philosophers want more power
tamsin shaw
Canto: Well I suppose the apparent detection of gravitational waves should be capturing our attention more than anything else right now, but it’s very well described in The Economist, and in many other places, and we’re no astrophysicists, and we did promise to focus a bit more on philosophical issues, so…
Jacinta: But we’re no philosophers. But we’re philosophasters at least, so let’s have a go.
Canto: Well I came across an article on Three Quarks Daily which vaguely gave me the irrits, so with your help I want to explore why.
Jacinta: Right. The essay is called ‘The psychologists take power’, the author is Tamsin Shaw and it was originally published in the New York review of books.
Canto: Yes, and on reading it in full I find it an interesting but confused piece, which seems to take the failings of certain individual psychologists as an example of the failings of psychology as a whole, and even of neurology. Shaw seems to be entering the philosophy versus science debate, on the side of philosophy, but I don’t find her arguments convincing.
Jacinta: The essay seems to divide into two parts, first a general critique of psychology and neurology, which can be summed up by the title of a philosophical essay by Selim Berker, which she quotes approvingly, ‘the normative insignificance of neuroscience’. The second part is an account of how certain professional psychologists, practitioners of the ‘positive psychology’ pioneered by the influential Martin Seligman, colluded with the US government in providing dubious evidence for the psychological effectiveness of torture in eliciting valuable information from ‘enemies of the state’. Shaw clearly wants to link these unethical practices to what she might want to call ‘the normative insignificance of psychology’.
Canto: Yes, and it’s a bit of a dangerous game – you might as well label Heidegger’s allegiance to the Nazi party, or Althusser’s murder of his wife, as examples of ‘the normative insignificance of philosophy’.
Jacinta: Ha, well Althusser was declared insane at the time, no doubt by psychologists, who would be examining Althusser to determine whether he was, while strangling his wife, capable of understanding and following the normative rules of his society. Such determinations are hardly normatively insignificant, even though, no doubt, individual psychologists might make different determinations, due to levels of competence, corruption, ideological considerations and so forth.
Canto: Right, but let’s look more closely at Shaw’s essay, and pick it apart.
Jacinta: Okay, but first let’s make a philosophasters’ confession. Shaw mentions eight or so books or sources at the head of her essay, which form the basis of her discussion, but of those we’ve only read one – Pinker’s eloquent tome, The better angels of our nature. And we don’t intend to bone up on those other texts, though no doubt we’ll refer to our own reading in our responses.
Canto: And we are reasonably familiar with Jonathan Haidt’s work and ideas.
Jacinta: So Shaw begins her essay with the overweening ambition of behaviourist extraordinaire B F Skinner, a pretty soft target these days. I have no problems with criticising him, or Freud or any other psychologist whose theories get way out of hand. Shaw’s concerns, though, are specifically about the moral sphere. She feels that a new breed of psychologists, armed with neurological research, are making big claims about moral expertise. Here’s a quote from her essay:
Neuroscience, it is claimed, has revealed that our brains operate with a dual system for moral decision-making.
Canto: I like the ‘it is claimed’ bit. Claimed by who? Someone has put forward that hypothesis I’m sure, along with their reasons, but most neurologists bang on about neurology being a field in its infancy, and most findings are highly contested, it seems to me.
Jacinta: Shaw may be referring to the work of Daniel Kahneman – a psychologist not a neurologist – who distinguished between system 1 thinking (intuitive, less conscious, rough-and ready) and system 2 thinking (reasoned, conscious, more changeable depending on inputs and knowledge). But really there are many dual-process theories going back at least to William James. But Shaw is explicitly referring to the fMRI imaging work of the neurologist Jonathan Cohen, who analysed brain activity when subjects were asked to think about moral hypotheticals.
Canto: Yes and she’s quite straight about describing the two systems apparently highlighted by Cohen’s research and the brain regions associated with them, but becomes scathing in dealing with Joshua Greene, Cohen’s co-researcher, whom she quite deliberately introduces as a mere ‘philosophy graduate student’, whose interpretation of the research she describes thus:
Greene interpreted these results in the light of an unverifiable and unfalsifiable story about evolutionary psychology. Since primitive human beings encountered up-close dangers or threats of personal violence, their brains, he speculated, evolved fast and focused responses for dealing with such perils. The impersonal violence that threatens humans in more sophisticated societies does not trigger the same kind of affective response, so it allows for slower, more cognitive processes of moral deliberation that weigh the relevant consequences of actions. Greene inferred from this that the slower mechanisms we see in the brain are a later development and are superior because morality is properly concerned with impersonal values—for example, justice—to which personal harms and goals such as family loyalty should be irrelevant. He has taken this to be a vindication of a specific, consequentialist philosophical theory of morality: utilitarianism.
Jacinta: Okay, so here’s where psychology – especially evolutionary psychology – first comes under attack. It’s often said to present just so stories, which are necessarily highly speculative, as if they are facts. But I would question whether these speculations, or hypotheses, are unverifiable (forget about falsifiability, a term made popular by Karl Popper but which has come under heavy criticism since, both by scientists and philosophers of science, and I suspect Shaw has simply used it as a ‘double whammy’ to vilify Greene), to me they’re important and useful, and in any case are rarely presented as facts, at least not by the best psychologists.
Canto: So how do you verify this hypothesis, that fast, rough-and-ready responses for dealing with immediate dangers are systematically different from slower, more sophisticated responses that deal with the ‘impersonal violence’, the many restraints, justified or not, on our personal freedoms that we deal with on a daily basis?
Jacinta: Well one obvious way is through neurology, a scientific field still in its infancy as you say. Clearly the system 1 responses would be shared by other complex social mammals, whereas system 2 thinking is much more language-dependent and unique to humans – unless cetaceans have developed complex language, which is far from being out of the question. New techniques for mapping and exploring neural pathways are coming up all the time, as well as non-invasive ways of exploring such pathways in our closest mammalian relatives.
Canto: Good point. So to go to the second part of the above quote, Greene is presented (and I wonder about whether Shaw is fairly or accurately presenting him) as finding system 2 thinking as superior because it deals with more abstract and less personal values, whereas I would prefer to think of this system as a further adaptation, to a human existence that has become more socially complex, systematic and language-based. And in this, I’m apparently in line with the thinking of psychologists Shaw takes aim at:
Many of the psychologists who have taken up the dual-process model claim to be dismissive of philosophical theories, generally. They reject Greene’s inferences about utilitarianism and claim to be restricting themselves to what can be proved scientifically. But in fact all of those I discuss here are making claims about which kinds of moral judgments are good or bad by assessing which are adaptive or maladaptive in relation to a norm of social cooperation. They are thereby relying on an implicit philosophical theory of morality, albeit a much less exacting one than utilitarianism.
Jacinta: But I detect a problem here. You’ve talked about adaptation to the fact of growing social complexity, and the need to co-operate within that complexity. Shaw has written of a ‘norm of social co-operation’, by which she means an ethical norm, because she claims that this is the implicit philosophical theory of morality these psychologists rely on. But that’s not true, they’re not claiming that there’s anything moral about social complexity or social co-operation. We just are more complex, and necessarily more co-operative than our ancestors. So it’s kind of silly to say they’re relying on a less exacting moral philosophy than utilitarianism. It’s not about moral philosophy at all.
Canto: And it gets worse. Shaw claims that this phantom moral ethic of social co-operation is greatly inferior to utilitarianism, so let’s look at that normative theory, which in my view is not so much exacting as impossible. Utilitarianism is basically about the maximising of utility. Act in such a way that your actions maximise utility (act utilitarianism), or create rules that maximise utility (rule utilitarianism). So what’s utility? Nothing that can be measured objectively, or agreed upon. We can replace it with happiness, or pleasure, or well-being, or Aristotle’s eudaemonia, however translated, and the problem is still the same. How do you measure, on a large-scale, social level, things so elusive, intangible and personal?
Jacinta: Yes, and look at how laws change over time, laws for example relating to homosexuality, women’s rights, the protection of minorities, and even business practices, taxation and the like; they’re all about our changing, socially evolving sense of how to co-operate in such a way as to produce the best social outcomes. This can’t be easily bedded down in some fixed normative ethic.
Canto: Yes, Shaw seems to imply that some deep philosophical insight is missing from these psychologists which makes them liable to go off the rails, as the second half of her essay implies, but I’m very doubtful about that. But let’s continue with our analysis:
Rather than adhering to the moral view that we should maximize “utility”—or satisfaction of wants—they are adopting the more minimal, Hobbesian view that our first priority should be to avoid conflict. This minimalist moral worldview is, again, simply presupposed; it is not defended through argument and cannot be substantiated simply by an appeal to scientific facts. And its implications are not altogether appealing.
Jacinta: But surely she’s just assuming that ‘they’ – presumably all the psychologists she doesn’t like, or is it all the psychologists who posit a two-tiered system of decision-making? – take the view that avoidance of conflict is the highest priority.
Canto: Well I must say that Jonathan Haidt seems to take that view, and it’s something I find uncomfortable. So I agree with Shaw that Haidt ‘presupposes that the norm of cooperation should take precedence over the values that divide us’, and that this view is dubious. It’s just that I suspect my own view, that there are values more important than co-operation, is also a ‘presupposition’, though I dislike that word. But more of that later perhaps.
Jacinta: Right, so Shaw refers to the sinister implications of a minimalist Hobbesian worldview, supposedly held by these psychologists. What are they?
Canto: We’ll get there eventually – perhaps. Shaw describes the work of the ‘positive psychology’ movement, stemming from Martin Seligman and practised by Haidt among others, including Steven Pinker, whose book The better angels of our nature was apparently influenced by this movement:
In that extremely influential work Pinker argues that our rational, deliberative modes of evaluation should take precedence over powerful, affective intuitions. But by “rationality” he means specifically “the interchangeability of perspectives and the opportunity the world provides for positive-sum games,” rather than any higher-order philosophical theory. He allows that empathy has played a part in promoting altruism, that “humanitarian reforms are driven in part by an enhanced sensitivity to the experiences of living things and a genuine desire to relieve their suffering.” But nevertheless our “ultimate goal should be policies and norms that become second nature and render empathy unnecessary.”
And here’s where I see another problem. Pinker is here criticised for not subscribing to any ‘higher-order philosophical theory’, but Shaw doesn’t attempt to outline or give examples of such higher-order theories, though she does refer to empathy – an important factor, but one that doesn’t obviously emerge from philosophy.
Jacinta: Right, and we’ve already referred to utilitarianism and its problems. This reminds me that years ago I read a sort of primer on ethics, I think it was called Moral Philosophy, in which the author devoted chapters to utilitarianism, Kantianism, rights theory and other ethical approaches. In the final chapter he presented his own preferred approach, a sort of neo-Aristotelianism. I was intrigued that he felt we hadn’t made much progress in philosophical ethics in almost 2,500 years.
Canto: Well, his may be a minority view, but it’s doubtful that our changing laws derive from philosophical work on normative ethics, though this may have had an influence. I do think, with Haidt, that there’s a great deal of post-hoc rationalisation going on, though I’m reluctant – very reluctant actually – to embrace the relativism of values. And this brings me to the nub of the matter, IMHO. To go back to an old favourite of mine, Hume: ‘reason is and ought only to be the slave of the passions’. A fairly notorious pronouncement, but I take the passions here to be something very basic – the fundamental drives and instincts, largely unconscious, that characterise us as humans…
Jacinta: But doesn’t Hume break his own is-ought rule here? He says that our passions rule our reason, which may or may not be true, but does it follow that they ought to?
Canto: Please don’t complicate matters. Hume also wrote this, in An Enquiry Concerning the Principles of Morals:
In all determinations of morality, this circumstance of public utility is ever principally in view, and wherever disputes arise, either in philosophy or common life, concerning the bounds of duty, the question cannot, by any means, be decided with greater certainty, than by ascertaining, on any side, the true interests of mankind.
So these true interests of mankind…
Jacinta: Hang on, so there he goes again, gaily bounding over his own is-ought barrier, saying that in order to work out what we ought to do we need – pretty well absolutely – to determine our interests, what in fact makes us human, what we actually are.
Canto: Well, precisely…
Jacinta: Or what we have evolved to become, which might amount to the same thing. So we need to study our evolution, our genes and genetic inheritance, our brain and its inheritance, and adaptive growth, and maybe the physics of our bodies…
our old Scottish mate Davey Hume, doyen of skeptics, whose is-ought distinction has been widely misinterpreted, we suspect
Canto: So we need neurology, and genetics, and palaeontology, and physics and psychology, all of which contribute to an understanding of what we are. Without them, normative ethics would be empty theorising.
Jacinta: So I suppose you’re going to write a rejoinder to this ‘normative insignificance of neurology’ essay? Something like ‘the insignificance of normative ethics without neurology’?
Canto: Ha, well that would require reading Selim Berker’s essay, which I’m not sure about – so many other things to explore. But I should end this discussion by saying a few words about the second half of Shaw’s article – and I’ll pass over many other points she’s made. This section deals with the collusion of some psychologists, practitioners of the above-mentioned ‘positive psychology’, with the CIA and the US Department of Defence in the commission of torture.
Jacinta: And what exactly is this ‘positive psychology’?
Canto: Well, to explain that would require a large digression. Suffice to say for now that it’s about using psychology to make us more resilient, and in some sense ethically superior, or more benign, humans. Shaw dwells on this at some length, but claims that in spite of much rhetoric, these psychologists can only offer what she calls the bare, Hobbesian ethic of avoidance of strife. However, she herself is unable to point to a more robust, or a deeper, ethic. She presumably believes in one, but she doesn’t enlighten us as to what it might be. And this is very striking because the tale of these psychologists’ collusion with the Bush administration on torture, and the huge financial gain to them in applying ‘learned helplessness’, a theory of Seligman’s, to the application of torture, is truly shocking.
Jacinta: So it would be a question of what, in their make-up, allowed them to engage in such unethical behaviour, and was it the lack of a deep ethical understanding, beyond ‘bare Hobbesianism’?
Canto: Right, and my answer would be that, although two psychologists took up this lucrative offer to ‘serve the state’, there would have been others who refused, and would any of them, on either side, have made their decision on the basis of some rigorous normative ethic?
Jacinta: I’m quite sure I wouldn’t have colluded with that sort of thing for all the terracotta warriors in China, but I’m also sure it wouldn’t have been for deep philosophical reasons. I just have a kind of visceral revulsion for physical violence and bullying as you know, and I wouldn’t be able to live with myself if I’d facilitated the premeditated cruel and unusual punishment of others. I’m not even sure if it’s about empathy, but it’s not a particularly reasoned position.
Canto: Yes, and so the only way to understand why some people are more prone to do unethical things – actions outside of the ever-changing standards of community ethics – might be to look at individual psychology, and neurology, and genetics, which takes us further away from normative ethics than ever.
Jacinta: Yes, and didn’t we read, in Sam Kean’s The tale of the duelling neurosurgeons, about a poor fellow in his mid-fifties who suddenly started engaging in paedophile acts, something he had never showed any signs of before? A brain scan revealed a large tumour pressing on parts of the brain responsible for higher-order decision-making (to put it over-simplistically). When the tumour was removed he returned to ‘normal’, until some time later he regressed to paedophile acts. A further scan showed they didn’t remove all the tumour and it had regrown. After another more successful operation he was cured and never diddled again. But the consequences of his actions for his victims when ‘not himself’ would have required him to be punished, on a consequentialist ethical view, wouldn’t they?
Canto: Very good point. And yet, and yet… can it be true that we’ve barely gone further in our ethics than the Golden Rule, or Aristotle’s mean between extremes?
Jacinta: We’re animals, don’t forget. Okay we’re animals that have managed to detect waves from space that are a tiny fraction of the diameter of a proton, but we’re still not that good at being nice to each other. And the extent to which we’re able to be nice to each other, and follow social norms, that’s a matter of our individual psychology, our neurology, our individual and cultural circumstances, our genes and our epigenetic profile, so much particular stuff that philosophical ethics, with its generalities, can’t easily deal with.
What is a trisomy?
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.
Canto: 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.