Archive for the ‘other life’ Category
a closer look at bonobos, enfin
As this blog is called what it is, I’ve decided to read the entire, long, Wikipedia article on bonobos to get a more subtle and comprehensive feel for their society and how it shapes their individuality – though of course I’ll continue to write on completely different subjects. What I’m finding so far is that there are nuances, as you would expect, and as we find in human societies. And of course it would be the same with other social species – a member of the normally less dominant gender will, through proven capabilities or particular personality traits, be given a more prominent role than usual, and leadership of or status within the group is not solely based on gender. Ranking may have a degree of fluidity based on behaviour and alliances. Not all males are subordinate and not all females are bosses. Nevertheless, bonobos are definitely matriarchal – just as chimps are patriarchal, also with some fluidity.
It surprised me when I learned, some years ago, that bonobos have a ‘male philopatric’ society. The term conveys a gender distinction – the male stays ‘at home’ for mating and reproduction, while the female moves to another group for that purpose. This occurs in some human societies too. While visiting the Tiwi Islands just north of Darwin, I was told by our islander guide that he had just ‘lost’ his sister, who had moved to another tribal group to marry, meaning that their connection was permanently broken. His culture actually forbade him to have any more contact with her. So the early Catholic Church prohibitions against first, second, third and fourth cousins marrying, as described in Joseph Henrich’s historical account of the WEIRD world, as well as many long-held cultural traditions of Australasia and elsewhere, likely hark back to our hominid ancestors.
In any case, male philopatry doesn’t seem very matriarchal. There are of course good reasons for philopatry (male or female) in general, as well as good reasons for its opposite, male or female dispersal, which inevitably means that these behaviours, their causes and consequences, are widely disputed. I think I’ll return to this issue in another post.
A particularly interesting feature of bonobo culture, fairly recently recognised, is co-operation between two separate groups, or troupes. This was in the Congo’s Kokolopori Bonobo Reserve, which may, I think, represent a space between ‘the wild’ and ‘captivity’, and so may influence behaviour. From Wikipedia:
Over two years of observation, researchers witnessed 95 encounters between the groups. Contrary to expectations, these interactions resembled those within a single group. During these encounters, the bonobos engaged in behaviours such as grooming, food sharing, and collective defense against threats like snakes. Notably, the two groups, while displaying cooperative tendencies, maintained distinct identities, and there was no evidence of interbreeding or a blending of cultures. The cooperation observed was not arbitrary but evolved through individual bonds formed by exchanging favors and gifts. Some bonobos even formed alliances to target a third individual, demonstrating a nuanced social dynamic within the groups.
This contrasts importantly with the deadly clashes between groups of chimpanzees observed by Goodall and others.
Bonobos engage in tongue-kissing, the only non-human creatures observed to do so, at least thus far. And this brings us to sex, a difficult topic to write about, even in a blog nobody reads, given so many cultural and religious tabus swirling around it in human society. So, best just to be descriptive, without making comparisons to H sapiens.
Bonobos aren’t monogamous, and they engage in sexual activity from an early age. It is mostly masturbatory, and indiscriminate, with the possible exception of mothers sexually engaging with adult sons. Heightened sexual activity often occurs when rich food sources are found, in which the masturbatory sex often occurs in large groups, increasing generalised bonding. Female masturbation is helped along by the fact that their clitorises ‘are larger and more externalised than in most mammals’. Well, here, comparison with humans is instructive:
… while the weight of a young adolescent female bonobo “is maybe half” that of a human teenager, she has a clitoris that is “three times bigger than the human equivalent, and visible enough to waggle unmistakably as she walks.
All quotes here are from Wikipedia, unless otherwise stated. The most common sexual combo is female-female. Their face-to-face, body-to-body interactions are referred to as genito-genital (G-G) rubbing, which is often accompanied by loud noises, hopefully of pleasure.
So, while female-female masturbation is the most practised sexual behaviour of the species, enhancing bonding against any male threats, male-male masturbation is also a regular thing:
The most common form of male–male mounting is similar to that of a heterosexual mounting: one of the males sits “passively on his back [with] the other male thrusting on him”, with the penises rubbing together because of both males’ erections
Clearly sexual activity is encouraged and valued as the most essential feature of bonobo society, and is practised in a variety of ways – penis-fencing, rump-rubbing, genital massaging, oral sex (among males) and, as mentioned, tongue-kissing. Adult-child sex is more common in males than females, though there’s no penetration. Is this because they’re avoiding pain, or because they know the connection with pregnancy? The general scientific consensus is that non-human species engage in sex based on instinct, hormones and such – that’s to say, more or less unconsciously without being aware of possible or likely consequences. I’m not entirely convinced, especially re our closest relatives, but how can this be tested? In any case, regardless of all this sex play, bonobo birth rates are no higher than those of chimps.
Unsurprisingly bonobo social relations are just as complex as those of chimps, and perhaps also humans, with personal animosities, rivalries and close friendships within and between genders, and the fact that infanticide in bonobo society hasn’t been observed isn’t proof that it hasn’t happened – after all, we’ve only known of the existence of bonobos for a little under a century. Still, bonobos are definitely different, and in what I would call an inspiring way. You could say that sex becomes a feel-good strategy, but also a way of diminishing any sense of male ownership of offspring. As Wikipedia puts it:
The strategy of bonobo females mating with many males may be a counterstrategy to infanticide because it confuses paternity. If male bonobos cannot distinguish their own offspring from others, the incentive for infanticide essentially disappears. This is a reproductive strategy that seems specific to bonobos; infanticide is observed in all other great apes except orangutans. Bonobos engage in sexual activity numerous times a day.
Anyway, enough of sex, let’s explore violence. Chimps, as mentioned, tend to be hostile to those not in their own troupe, and even patrol their own borders, looking for trouble. Very West Side Story. And yet, to my surprise, bonobos, are more violent in general.
In the wild, among males, bonobos are more aggressive than chimpanzees, having higher rates of aggressive acts, about three times as much. Although, male chimpanzees are more likely to be aggressive to a lethal degree than male bonobos which are more likely to engage in more frequent, yet less intense squabbling. There is also more female to male aggression with bonobos than there is with chimpanzees. Female bonobos are also more aggressive than female chimpanzees, in general. Both bonobos and chimpanzees exhibit physical aggression more than 100 times as often as humans do.
All of this sounds interesting, but ‘aggression’ might be a little more difficult to define than we think. In humans, for example, accusatory or bullying language, or the sharing of images, can be used aggressively without anything physical occurring. It has even been known to cause the victim to commit suicide. We have subtler and often more effective ways to make others suffer, and ‘non-physical’ aggression may have a physical, even deadly, impact. It is also a way of getting around laws prohibiting physical violence.
In any case, surely a major reason for the supposed greater physical aggression of chimps and bonobos, and doubtless other apes, compared to humans, is how we ‘count’ aggression. Is carpet-bombing physical aggression? Nuclear warfare? The wholesale slaughter of the Jews and the Congolese? The massacres of the ‘Crusades’? How can we not count remote, push-button slaughter, or starving people to death behind walls, or burning them to death in buildings, as physical aggression? Methinks there’s need for a rethink.
So let’s turn to something less controversial. Like all the great apes, bonobos pass the self-awareness mirror test, and it’s clear that the variations in their vocalisations have meaning, though whether they rise to the standard of a proto-language is a matter of definition. They also use many meaningful hand gestures.
A famous example of a bonobo being taught to communicate using a keyboard, and to respond effectively to whole sentences, is that of Kanzi:
Kanzi’s vocabulary consisted of more than 500 English words, and he had comprehension of around 3,000 spoken English words… Kanzi is also known for learning by observing people trying to teach his mother; Kanzi started doing the tasks that his mother was taught just by watching, some of which his mother had failed to learn….
Kanzi was also taught how to make simple stone tools, though he found a method of making them in his own bonoboesque way. There seems no doubt that effective rapport between bonobos and humans will benefit both species.
Finally, there’s the ecological importance of bonobos. They’re essentially one of the two apex species of their region, the other being elephants. Both species are frugivorous, and their ecological role is vital:
It is estimated that during its life, each bonobo will ingest and disperse nine tons of seeds, from more than 91 species of lianas, grass, trees and shrubs. These seeds travel for about 24 hours in the bonobo digestive tract, which can transfer them over several kilometers (mean 1.3 km; max: 4.5 km), far from their parents, where they will be deposited intact in their faeces. These dispersed seeds remain viable, germinating better and more quickly than unpassed seeds. For those seeds, diplochory with dung-beetles (Scarabaeidae) improves post-dispersal survival.
Diplochory means two-phase seed dispersal, using more than one vector or carrier.
Anyway, I think that’s more than enough info for one post. The Wikipedia article on bonobos makes for a very solid book chapter, with 178 references, so far. And it ends nicely with informing us all of the annual World Bonobo Day, established in 2017. No prizes should be given for guessing the date!
References
https://en.wikipedia.org/wiki/Bonobo
Joseph Henrich, The WEIRDest people in the world: how the West became psychologically peculiar and particularly prosperous, 2021
other minds, other ways: killer whales etc
So in my quest to find inspiration as a wannabe female supremacist, I’ve been learning bits and pieces about octopuses (fascinating but way too bizarre and solitary to be role models), elephants, coyotes, lions, killer whales, lemurs, and of course bonobos. So in this piece I’ll focus on cetaceans, and killer whales in particular.
I’m coming close to the end of Carl Safina’s book Beyond Words: what animals think and feel, which is just what the matriarch ordered. Not that all the social animals he describes are matriarchal, but they’re all intelligent, complex and very much worth reflecting upon and valuing, especially considering how much we have done to them and to the environments they rely on.
So cetaceans are all complex ocean-dwelling mammals. There are about 90 species and they’re generally divided into whales, dolphins and porpoises. Safina introduces killer whales as ‘the world’s largest dolphins’, and quotes a remark from Herman Melville’s Moby Dick, ‘Exception might be taken to the name bestowed upon this whale… for we are all killers’. Humans particularly. Safina’s first chapter on them is called ‘Sea Rex’, and introduces them so:
Feared in our own time by even the sea’s greatest whales, killer whales exert power without peer since dinosaurs sighed out, sixty-five million years ago. But the killer’s subtle, sensitive side makes a hunter with complex notes that T rex could never have hoped to emulate: intelligent, maternal, long-lived, cooperative, intensely social, devoted to family. They are, like us, warm-blooded milk-makers, mammals whose personalities are really not much different from ours. They’re just a lot bigger. And notably less violent.
I knew before reading this book that these whales were also called orcas, and in fact thought the ‘orca’ term was a replacement, a less pejorative term, but maybe not, as it’s a latin reference to a demonic underworld. The Latin name is Orcinus orca, and there are various other names bestowed on them by sea-faring cultures. Safina prefers the term ‘killer’, always bearing in mind human capacities in that regard.
They’re matriarchal, the females being, as with elephants, the knowledge-keepers and the guides for the pods in their long migratory travels. And they’re very sexual, always a big interest of mine. In describing a party-style gathering that combined three pods, Safina noted the ‘x-rated’ style of their play. Male-male sex play is particularly notable, due to those things males have – ‘three-foot wangers draped over each other’, was one description re the adult males, and as for the youngsters, ‘soon after they stop nursing, there’s a lot of rolling around with their little snakes out’. This sex play is common to many dolphin species, and according to Safina, bottlenose dolphins engage in more same-sexual behaviour than any other known creature. Clearly bonobos need to lift their game.
Unsurprisingly, Safina makes comparisons with elephants:
As with elephants, each killer whale family’s elder decision-making matriarch has memorised the family’s survival manual, maintaining knowledge of the region, the routes and island passes, the rivers where salmon concentrate in their seasons, and so on. She’s often out in front.
But one glaring difference is that killer whales kill, even other, much bigger whales, while elephants are strictly vego. And they’re quite ruthless killing machines, though they’ve never been known to kill humans, in or out of the water – they’re too intelligent for that.
But their relations with humans are even more interesting, if the stories told to Safina are to be believed – stories told about various dolphin species. For example, killer whale pods (the term given to particular extended-family groups that hunt and play together, as I understand it), appear able to distinguish between vessels carrying nice humans and those nasty ones out to hunt or capture them. At a time just before laws were introduced to prevent organisations like Sea World from capturing baby whales, whole whale pods would hang around observer boats that they knew to be friendly and safe. Another story told of a whale pod guiding a small whale-friendly boat out of Puget Sound in a dangerously thick fog. Safina relates other stories told to him of captive dolphins (killer whales also being dolphins) engaging in highly intelligent trickery to wangle extra food from their captors. So much of this and other behaviours indicate that we’ve barely begun to comprehend the minds of these creatures, adapted to environments so far removed from our own.
Of course, with such ‘other-worldly’ creatures, it may be hard to tell myth from reality. They have saved dogs from drowning – plausible, they would have noticed dogs hanging around humans, and would not recognise them as potential food. Other behaviours, from playful to life-saving, towards humans they know to be whale-friendly, are more mysterious and perhaps simply indicate that we’re a long way form understanding minds so differently adapted from, and yet comparably complex as, our own. I’ve just started reading Dennett’s now 30-year-old Kinds of Minds, wondering if whales-dolphins will be looked at. I suspect not, or not much.
Finally, is there a way to associate those cetacean species that are female dominant as being different from those that aren’t? Or is their water-world so alien to us that it’s, so far, difficult to tell? And yet, their ancestry is terrestrial…
Wikipedia lists 94 species, all of which are uniparous (giving birth to one child at a time) as far as we know, and maternal care of offspring is intense and long-lasting, with paternal care being minimal at best – though pods are generally close-knit. Reproductive rates are low. This quote from a Royal Society paper, ‘Causes and consequences of female centrality in cetacean societies’, linked below, might help:
… every cetacean calf is a significant investment, and offspring care is central to female fitness. Here strategies diverge, especially between toothed and baleen whales, in terms of mother–calf association and related social structures, which range from ephemeral grouping patterns to stable, multi-level, societies in which social groups are strongly organized around female kinship. Some species exhibit social and/or spatial philopatry [remaining in same group or place, or returning there for breeding] in both sexes, a rare phenomenon in vertebrates. Communal care can be vital, especially among deep-diving species, and can be supported by female kinship. Female-based sociality, in its diverse forms, is therefore a prevailing feature of cetacean societies. Beyond the key role in offspring survival, it provides the substrate for significant vertical and horizontal cultural transmission, as well as the only definitive non-human examples of menopause.
The paper goes on to emphasise what Safina also points out, that ‘we know almost nothing about the social structure of most…. cetacean species’. What Safina does provide is a fund of pretty convincing anecdotal evidence of the complex understanding of human behaviour displayed by those species we’ve had contact with, in the wild and in captivity. And considering the obvious importance of females in those cetacean societies we’ve observed, I’m heartened by the paper’s emphasis on my own great topic of interest:
This [understanding of female roles in cetaceans] has important implications for understanding socio-cultural changes in modern human societies, where, for example, a comparative understanding of female social roles can guide thinking about sources and solutions to the problem of underrepresentation of women in positions of leadership.
So I haven’t yet fully digested this lengthy paper, so I’ll leave it to my next piece to report on it.
References
Carl Safina, Beyond words: what animals think & feel, 2016
octopuses r n t us
I watched a video yesterday on those amazing sea creatures and was reminded of a couple of books I read a few years ago by Peter Godfrey-Smith, Other minds: the octopus and the evolution of intelligent life, and Metazoa: animal minds and the birth of consciousness. Yes, again it’s about being engrossed and then more or less forgetting everything, so this time I won’t go on about myself and focus solely on octopuses. There are around 300 species of these shape-and-colour-shifting cephalopods, ranging in size from the Giant Pacific (the largest ever found weighing at about 270 kgs) to the Octopus wolfi (less than a gram). Which makes me wonder, how smart could such a mini-octopus be…?
Octopuses have been living in our oceans for some 300 million years, pre-dating the dinosaurs. They are invertebrates, i.e no backbone, but they do have hard beaky bits, the only part that can’t shape-shift. They’re famously solitary, living in home-made rock shelters, or shells or crevices – in fact in all sorts of innovative hideaways, and they’re not very long-lived at all, for all their smarts. The Giant Pacific lasts about five years at most, others not so much. Basically, they live to breed, then they die – males and females alike. Talk about a mind-blowing orgasm. This is called semelparity, which contrasts with iteroparous us. There are sex-based differences though, in this senescence. The females guard their eggs for a while, wasting away and generally dying just as the eggs hatch. This wasting process is similar in both sexes (though sometimes the male is killed by the female), and is brought about by secretions of the optic gland, ‘an endocrine gland located near the optic lobes, between the brain and eyes’, according to AI, which doesn’t lie. Anyway, this death-on-giving-birth system ensures, if that’s the word, that every new-born octopus is an orphan. Nothing is learned from their parents. They have to rely on their own smarts.
So what’s most interesting about them, surely, is the stuff that makes them think, from the get-go. It’s not a brain, in the mammalian or birdian sense, it’s a kind of decentralised nervous system. They do have a brain, of sorts, but they have eight other ‘arm-brains’. So each arm works separately but they must also be co-ordinated for the creature to get anywhere. Hard to work all that out, but then they’ve had 300 million years to do it. As to how many neurons they have, you can imagine, with the vast difference in species sizes, that it varies considerably. The common octopus, Octopus vulgaris, has about the same number as a dog, two-thirds of which are in the arms, the rest in the head. Nine brains, sort of. It has the largest brain-to-body mass of any invertebrate, unsurprisingly. They’re very visual, and can distinguish human faces, and even make friends with them, sort of. The award-winning documentary ‘My octopus teacher’ apparently demonstrates this (I haven’t seen it, but I will, and I’ve watched a documentary on the documentary, and even that was an emotional experience).
So octopuses can be added to the list of smart, even super-smart critters, but there’s something very very different about them, it seems to me. They’re solitary, and this doesn’t seem to be emphasised enough. They’re orphans, effectively. Of course they mate, because it takes two, but they don’t have mates in the Aussie sense.
Think of what this means. They don’t have parents, or siblings, or relatives – at least not that they know of, though the giant Pacific octopus lays tens of thousands of eggs before it drops dead. They don’t have playmates or teachers. Nothing is passed from generation to generation. Nothing is accumulated. They have no society. Remember the apocalyptically imbecilic remark of Margaret Thatcher, ‘there’s no such thing as society’? Maybe she’d mistaken herself for an octopus. For me, it’s due to the society that I live in that I can write on this laptop, or that I can read or write at all. Through my society I’ve learned something about the ancient Egyptians and Minoans, about Plato and Aristotle, about Voltaire and Diderot, Newton and Maxwell, Planck and Einstein. I’ve learned to play and appreciate the skills of soccer, pool and table tennis. I’ve learned of the joys and miseries associated with countless alcoholic beverages, and the odd not quite licit drug. I’ve driven cars, flown in planes, studied at a university, and sampled many other pleasures, as well as pitfalls, that my WEIRD world has provided. All, or most, of this stuff was around before I was born. They were the accumulations of our culture, part of what all we humans plug into. Octopuses, living and dying for hundreds of millions of years, have had none of that. To survive, they’re still doing what they were doing when our ancestors were synapsid tetrapods, likely sharing their oceans. And of course, they may well survive us. But have they had as much fun?
References
Peter Godfrey-Smith, Other minds: the octopus and the evolution of life, 2017
on free will and libertarianism 1: introducing some issues
I vaguely remember this book annoying me 35 years ago
Canto: So I’ve wanted to get back to this issue for some time, as it’s been on my mind, to connect an increasingly prevalent political ideology (or so it seems to me) with an increasingly tenuous philosophical position with regard to free will, but I’m not sure whether to start with the politics or the philosophy.
Jacinta: Well I think I can dispose of it all quite quickly. Free will’s a myth and individual freedom, however defined, has gotten us nowhere as a species. That’s it – so it’s off to the pub?
Canto: Well, that might be an interesting starting point, but I think we might need to put some flesh on the bones of those arguments, if I may cannibalise a cliché, or whatever.
Jacinta: Hmmm. So you really think there’s more to say?
Canto: Well I do feel the need to account for my change of position over several decades. Of course I’ve always been a determinist – the whole cause-effect relationship underpins our understanding of all human and non-human behaviour. I don’t think even quantum mechanics disrupts it too much, and to the extent it does, it certainly doesn’t do so in favour of human free will. But way back in the late seventies, when I was first introduced to the topic, ‘hard determinism’ as the term was then, was so out of fashion, and seemed to allow so little wiggle room for our actions, that I kind of assumed it was the province of attention-seeking extremists, or something. And of course it did seem a bit deflating to the human spirit, and all that.
Jacinta: So now you don’t mind a bit of deflation?
Canto: Well, over time, I reflected on my background, and perhaps also on the backgrounds of the philosophers and academics putting forward the compatibilist arguments – that somehow free will is compatible with determinism and even dependent on it. I found this later in Dennett’s book Elbow room, and I think there was some of it in Pinker’s The blank slate too. What I found was a kind of disdainful, and dare I say upper-middle class, attitude to ‘wrong-doers’ who need to be held accountable for their actions. And as a person who grew up in one of the most working-class and disadvantaged suburban regions in Australia, I felt defensive for the people around us (our family were better off than most), their bootlessness and despair. It certainly rubbed off on me in my teen years. I didn’t exactly bear a grudge against the world, but I certainly never had any inspiring teachers or adult figures who encouraged my scintillating intellect.
Jacinta: Okay, enough about you, what about the argument?
Canto: Well let’s look at free will first. The compatibilist argument is that free will is itself a determining factor in the decisions you make. You weigh the pros and cons in your mind, without undue influence from other sources, and determine to have tea with your breakfast instead of coffee, for the first time in months. Of course you’ve done this of your own free will, just as you’ve chosen to feed the dog instead of throwing her out of your 10th storey window, etc etc. The favourite term is ‘you could’ve done otherwise’.
Jacinta: But you didn’t.
Canto: And the feeling that you could’ve done otherwise is also determined, as is the feeling of regret that you quit that job when you should’ve stayed on, that you didn’t make that move interstate, that you didn’t keep in touch with person x, etc. The sense that we could have been better than what we are, could have done better than what we did, these are everyday feelings that we’re never free from. But getting back to compatibilists, they try to have the best of both worlds by claiming that the self is this autonomous determining factor in decision-making. It all revolves around this self. Presumably the developed self, since obviously the two-year-old self is not fully responsible for her actions.
Jacinta: Ah yes and there’s where it all falls apart. Where does this ‘self’ come from? We start as a fertilised egg, the width of a human hair. No brain, no heart, no belly, no skin, just genetic potential. Clearly we’re not making decisions. Nine months later, we’re born, fortunately with all those organs. But surely we’re not making our own decisions at this stage. And we’ve been subjected to a lot in this period, nutrients of all sorts, twists and turns, bumpings and grindings, the sounds of laughter, tears, music, shouts, squeals, long silences, all of which may influence our patterns of neural development both inside and outside the womb. All of which lay down the pattern of our future self, our future ‘free will’.
Canto: Yes, and from that time on its ‘meet the parents’, or caregivers, and/or our siblings and our homes, the furniture of our early lives. Not our choices. I think the no-free-will argument can be most persuasive when you can persuade the opposite side of the most obvious limitations, which are all big ones – for example you don’t get to choose your parents, your place or time of birth/conception, or even the species you were born into. So with those huge limitations accepted, you start to home in on the wiggle room the freewillers have left. Presuming they’re compatibilists, that’s to say determinists, they must accept that all that ultra-connecting and later trimming of neurons in early childhood has nothing to do with personal choice. And yet they try to argue that after all that connecting and trimming, when they’re a ‘fully determined self’, this self goes into auto mode, that of a self-determining self. Which presumably coincides with ‘adulthood’.
Jacinta: Right. As if our courts, or our laws, have solved the free will problem.
Canto: Yes, but it’s a bit like those claims for perpetual motion machines, that can produce output with no energy input. They’re as mythical as free will. The self is essentially only useful as an identifier, and it’s obviously very useful for that. And every self is unique, and perhaps that’s what confuses people. A person can be eccentric, ‘exceptionally different’, in good or bad ways, and we say ‘she’s really her own person’ or ‘she goes her own way’, and strictly speaking that can be said of everyone, whether human, fish or fowl, or of the plants on our balcony, or the jacarandas on our street, each one of which is unique, but not of their own free will.
Jacinta: We mistake complexity for free will, perhaps. Complexity is everywhere on this life-coated planet, but the human brain beats it all for complexity. We carry those things around, we feel it, and so we feel free, to possibly do anything, be anything, learn anything, commit anything. And feel proud when we do the ‘right’ thing, make the requisite effort and so on.
Canto: It’s arguable that this feeling of free will is important for our success. Or our striving. It’s up to you to work hard to pass that exam, to build a successful business, to become a regular in the first team, whatever. The sense of freedom can be exhilarating, though it might be just as obviously caused as the health-giving freedom ‘experienced’ by a plant moved from a nutrient-poor soil to a nutrient-rich one. Something in our environment makes us more successful than the guy down the road, or in Africa, but we don’t want to place too much emphasis on that environment, especially if we know we’ve put in an effort to succeed.
Jacinta: Okay, so what about punishment? As you’ve said, we might claim too much credit for our successes, isn’t a corollary that we place too much blame on those who ‘fail’, who give in to their peers’ world of violence and contempt? Punishment is mostly about deterrence, they say, but isn’t there a better way to treat people than this?
Canto: That’s an interesting question, and of course a complex one. We should talk about it next time.
a bonobo world 62: more species, and then back to the point of it all
male aggression – it’s everywhere
Canto: Okay, let’s look at other cetaceans. There are 89 species, so we can’t cover them all. There are toothed and baleen types, but all dolphins and porpoises are toothed. There are river dolphins and oceanic dolphins, and in terms of size, cetaceans range widely, so that we have names like northern right whale dolphin, southern right whale dolphin, false killer whale, pygmy killer whale and various types of humpback dolphin as well the humpback whale. So it might be that they’re as culturally various as humans. I’ll limit my examination, then, to four or five well-known species, with no pretence that any of them typify the whole.
Jacinta: Yes, when we talked about dolphins before, it was the common bottle-nose dolphin, right?
Canto: Essentially yes, and I’ll pick some of the best known cetaceans, avoiding those most endangered, because they’ll probably be the least studied in the wild. First, the humpback whale, which is a rorqual. Rorquals represent the largest group of baleen whales, and of course humpback whales are an iconic and fairly well researched species, as whales go. And one immediately interesting fact is that the females are on average slightly larger than the males.
Jacinta: Size usually matters.
Canto: And they can live up to 100 years. But let’s talk about sex, or courtship as the Wikipedia article on humpbacks charmingly describes it. You’ll be happy to know that humpbacks are polyandrous – that’s to say, females mate with many males during their breeding season. This is generally seen as the opposite of polygyny – one male mating with many females. In fact polyandry is more often seen in insects than in any other life forms. Humpbacks have even been known to have it off with other species. Wikipedia calls it hybridisation. There’s apparently a humpback-blue whale hybrid out there.
Jacinta: I assure you that when females rule the world – in nevereverland – any attempt to employ ‘euphemisms’ for fucking will be punished by instant castration.
Canto: Well you’ll also be amused to know that males fight over females.
Jacinta: How very unsurprising. But at least they sing, which almost compensates.
Canto: Yes, males and females vocalise, but the long, complex and very loud songs are produced by males. It’s believed that they help to produce estrus in the females.
Jacinta: The correct term is fuck-readiness.
Canto: In fact, researchers only think that because only males produce the complex songs. It’s a reasonable inference, but it could be wrong. Some think that the songs might be used to prove the male’s virility to the female, to make him more attractive. This supposedly happens with birdsong too.
Jacinta: Trying to think of human equivalents. Rocks in the jocks?
Canto: Oh no, too chafing. Being a good cook helps, I’ve found. But what with the obesity epidemic, that’s a balancing act. Anyway, those humpback boys put a lot of energy into their songs, which sometimes last for over 24 hours. Animals of one population, which can be very large, sing the same culturally transmitted song, which slowly changes over time. All interesting, but probably not much of a model for us. I can barely swim.
Jacinta: Well yes, it’s hardly sing or swim for us, but let’s turn to other cetaceans. What about blue whales?
Canto: Well it’s interesting to find that most websites don’t even mention their social life – it’s all about their ginormity, their big hearts, and their feeding and digestion. It took me a while to discover that they’re solitary creatures, which I suppose is common sense. Hard to imagine a superpod of blue whales out in search of a collective meal. They do sometimes gather in small groups, presumably for sex, and of course there’s a mother-calf relationship until maturity. As with humpbacks, the females are a bit larger than the males. What would that be about?
Jacinta: Well, some researchers (see link below) have discovered that male humpbacks favour the largest females, so there’s presumably sexual selection going on. And of course, they fight over the biggest females.
Canto: Well you can’t blame them for being macho. It be nature, and what do please gods.
Jacinta: Oh no, let’s not go there. Anyway, the largest females produce the largest and presumably healthiest offspring. They also found that the older females make the best mothers, which I’m sure is generally the case in humans too, mutatis mutandis.
Canto: So in conclusion, these mostly solitary creatures, whether they be cetaceans or primates, can’t be said to be patriarchal or matriarchal, but the males still manage to be more violent, or at least more cross with each other, than the females.
Jacinta: But it doesn’t have to be that way, hence bonobos.
Canto: Yes, but that makes me think. I hear that bonobos use sex to ‘ease tensions’, among other things. Tensions hints of violence, or at least anger. I’m wondering if that anger comes mostly from the males, and if the use of sex to dissipate that anger comes mostly from the females.
Jacinta: That’s a good question. There’s a site, linked below, which sort of looks at that question. It cites research showing that female bonobos gang up on male aggressors. The researchers found an absence of female-on-female aggression (perhaps less so than in the human world). According to this site – which may not be wholly reliable, as it’s really about humans and nightlife behaviour – female bonobos bond in small groups for the specific purpose of keeping males in line. How do they know that? They might be arguing from girl nightlife behaviour. I mean, who’s zoomin who?
Canto: The general point though is that among bonobos, males are more aggressive than females. Which isn’t to say that females can’t be aggressive, and not just in a defensive way.
Jacinta: This website also mentions something which is the general point of all our conversations on bonobos and humans and sex and well-being. It’s worth quoting in full:
Anthropological data analyzed by neuropsychologist James Prescott suggests societies that are more sexually open are also less likely to be violent. The key to understanding this correlation, however, is that it’s the society as a whole that is more sexually open and not just a small percentage of individuals.
Canto: That’s a good quote to get us back to humans. We need to look at this matter more closely next time. And the next and the next.
References
https://en.wikipedia.org/wiki/List_of_cetaceans
https://www.nbcnews.com/id/wbna29187881
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.
the unpredictable effects of permafrost thaw
This Aug. 12, 2009, photo shows a section of the vital Dempster Highway linking southern Canada with the Northwest Territories after it collapsed because warming temperatures caused the permafrost below to thaw. Permafrost melting from global warming is causing damage to infrastructure across the Arctic. (AP Photo/Rick Bowmer)
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.
permafrost thaw ponds around Hudson Bay, Canada
this one’s for the birds
Canto: If anybody doesn’t appreciate the beauty and complexity and general magnificence of birds they should pee off and never darken this blog again.
Jacinta: Right. Now what brought that on, mate?
Canto: Oh just a general statement of position vis-à-vis other species. Charles Darwin, an old friend of mine, was pretty disdainful of human specialness in his correspondence, but he kept a low profile – on this and everything else – in public. I want to be a bit more overt about these things. And one of the things that really amazes me about birds, apart from their physical beauty, is how much goes on in those teeny noggins of theirs.
Jacinta: Yes, but what really brought this on? I haven’t heard you rhapsodising about birds before.
Canto: You haven’t been inside my vast noggin mate. Actually I’ve been taking photos – or trying to – of the bird life around here; magpies, magpie-larks, crows, rainbow lorikeets, honeyeaters, galahs, corellas, sulphur-crested cockies, as well as the pelicans, black swans, cormorants, moorhens, coots and mallard ducks by the river, not to mention the ubiquitous Australian white ibis and the masked lapwing.
Jacinta: Well I didn’t know you cared. Of course I agree with you on the beauty of these beasties. Better than any tattoo I’ve seen. So you’re becoming a twitcher?
Canto: I wouldn’t go that far, but I’ve been nurturing my fledgling interest with a book on the sensory world of birds, called, appropriately, Bird sense, by a British biologist and bird specialist, Tim Birkhead. It’s divided into sections on the senses of birds – a very diverse set of creatures, it needs to be said. So we have vision, hearing, smell, taste, touch, and that wonderful magnetic sense that so much has been made of recently.
Jacinta: So we can’t generalise about birds, but I know at least some of them have great eyesight, as in ‘eyes like an eagle’.
Canto: Well, as it happens, our own Aussie wedge-tailed eagle has the most acute sense of vision of any creature so far recorded.
Jacinta: Well actually it isn’t ours, it just happens to inhabit the same land-form as us.
Canto: How pedantic, but how true. But Birkhead points out that there are horses for courses. Different birds have vision adapted for particular lifestyles. The wedge-tail’s eyes are perfectly adapted to the clear blue skies and bright light of our hinterland, but think of owl eyes. Notice how they both face forward? They’re mostly nocturnal and so they need good night vision. They’ve done light-detection experiments with tawny owls, which show that on the whole they could detect lower light levels than humans. They also have much larger eyes, compared with other birds. In fact their eyes are much the same size as ours, but with larger pupils, letting in more light. They’ve worked out, I don’t know how, that the image on an owl’s retina is about twice as bright as on the average human’s.
Jacinta: So their light-sensitivity is excellent, but visual acuity – not half so good as the wedge-tailed eagle’s?
wedge-tailed eagle – world’s acutest eyes
Canto: Right – natural selection is about adaptation to particular survival strategies within particular environments, and visual acuity isn’t so useful in the dark, when there’s only so much light around, and that’s why barn owls, who have about 100 times the light-sensitivity of pigeons, also happen to have very good hearing – handy for hunting in the dark, as there’s only so much you can see on a moonless night, no matter how sensitive your eyes are. They also learn to become familiar with obstacles by keeping to the same territory throughout their lives.
face of a barn owl – ‘one cannot help thinking of a sound-collecting device’, quoth researcher Masakazu Konishi
Jacinta: So they don’t echo-locate, do they?
Canto: No, though researchers now know of a number of species, such as oilbirds, that do. Barn owls, though, have asymmetrical ear-holes, one being higher in the head than the other, which helps them to pinpoint sound. It was once thought that they had infra-red vision, because of their ability to catch mice in apparently total darkness, but subsequent experiments have shown that it’s all about their hearing, in combination with vision.
Jacinta: Well you were talking about those amazing little brains of birds in general, and I must say I’ve heard some tales about their smarts, including how crows use cars to crack nuts for them, which must be true because it was in a David Attenborough program.
Canto: Yes, and they know how to drop their nuts near pedestrian crossings and traffic lights, so they can retrieve their crushed nuts safely. The genus Corvus, including ravens, crows and rooks, has been a fun target for investigation, and there’s plenty of material about their impressive abilities online.
seeing is believing
Jacinta: So what other tales do you have to tell, and can you shed any light on how all this cleverness comes in such small packages?
Canto: Well Birkhead has been studying guillemots for years. These are seabirds that congregate on cliff faces in the islands around Britain, and throughout northern Europe and Canada. They’re highly monogamous, and get very attached to each other, and thereby hangs another fascinating tale. They migrate south in the winter, and often get separated for lengthy periods, and it’s been noted that when they spot their partner returning, as a speck in the distance, they get highly excited and agitated, and the greeting ceremony when they get together is a joy to behold, apparently – though probably not as spectacular as that of gannets. Here’s the question, though – how the hell can they recognise their partner in the distance? Common guillemots breed in colonies, butt-to-butt, and certainly to us one guillemot looks pretty well identical to another. No creature could possibly have such acute vision, surely?
Jacinta: Is that a rhetorical question?
Canto: No no, but it has no answer, so far. It’s a mystery. It’s unlikely to be sight, or hearing, or smell, so what is it?
Jacinta: What about this magnetic sense? But that’s only about orientation for long flights, isn’t it?
Canto: Yes we might discuss that later, but though it’s obvious that birds are tuned into their own species much more than we are, the means by which they recognise individuals are unknown, though someone’s bound to devise an ingenious experiment that’ll further our knowledge.
Jacinta: Oh right, so something’s bound to turn up? Actually I wonder if the fact that people used to say that all Chinese look the same, which sounds absurd today, might one day be the case with birds – we’ll look back and think, how could we possibly have been so blind as to think all seagulls looked the same?
Canto: Hmmm, I think that would take a lot of evolving. Anyway, birds are not just monogamous (and anyway some species are way more monogamous than others, and they all like to have a bit on the side now and then) but they do, some of them, have distinctly sociable behaviours. Ever heard of allopreening?
Jacinta: No but I’ve heard the saying ‘birds of a feather flock together’ and that’s pretty sociable. Safety in numbers I suppose. But go on, enlighten me.
Canto: Well, allopreening just means mutual preening, and it usually occurs between mates – and I don’t mean in the Australian sense – but it’s also used for more general bonding within larger groups.
Jacinta: Like, checking each other out for fleas and such, like chimps?
Cant: Yeah, though this particular term is usually reserved for birds. Obviously it serves a hygienic purpose, but it also helps calm ruffled feathers when flocks of colonies live beak by jowl. And if you ever get close enough to see this, you’ll notice the preened bird goes all relaxed and has this eyes half-closed, blissed-out look on her face, but we can’t really say that coz it’s anthropomorphising, and who knows if they can experience real pleasure?
Jacinta: Yes, I very much doubt it – they can only experience fake pleasure, surely.
Canto: It’s only anecdotal evidence I suppose, but that ‘look’ of contentment when birds are snuggling together, the drooping air some adopt when they’ve lost a partner, as well as ‘bystander affiliation’, seen in members of the Corvus genus, all of these are highly suggestive of strong emotion.
Jacinta: Fuck it, let’s stop beating about the bush, of course they have emotions, it’s only human vested interest that says no, isn’t it? I mean it’s a lot easier to keep birds in tiny little cages for our convenience, and to burn their beaks off when they get stressed and aggressive with each other, than to admit they have feelings just a bit like our own, right? That might mean going to the awful effort of treating them with dignity.
Canto: Yyesss. Well on that note, we might make like the birds and flock off…
how the flock do they do that?
exoplanets – an introduction of sorts
Jacinta: So do you think we’ve hauled ourselves out of ignorance sufficiently to have a halfway stimulating discussion on exoplanets?
Canto: I think we should try, since it’s one of the most exciting and rapidly developing fields of inquiry at the moment.
Jacinta: And that’s saying something, what with microbiomes, homo naledi, nanobots and quantum biology…
Canto: Yes, enough to keep us chatting semi-ignorantly to the end of days. But let’s try to enlighten each other on exoplanets…
Jacinta: Extra solar planets, planets orbiting other stars, the first of which was discovered just over 20 years ago, and now, thanks largely to the Kepler Space Observatory, we’ve discovered thousands, and future missions, using TESS and the James Webb telescope, will uncover megatonnes more.
Canto: Yes, and you know, about the Kepler scope, l was blown away – this might be veering off topic a bit, but I was blown away in researching this by the fact that Kepler orbits the sun. I mean, I knew it was a space telescope, but I just assumed it was in orbit around earth, probably at a great distance to avoid interference from our atmosphere, but that we can position satellites in orbit around the sun, that really sort of stunned me, more I think than the exoplanet discoveries. Am I being naive?
Jacinta: No, not at all. Well, yes and no. Everything is stunning if you haven’t followed the incremental steps along the knowledge pathway. I mean, if you think, hey the sun’s a way away, and it’s really big and dangerous, best not go there, or something like that, you might be shocked, but think about it, we’ve been sending satellites around the earth for a long time now, and we know how to do it because we know about earth’s gravitational field and can calculate precisely how to harness it for satellite navigation. We’ve currently got a couple of thousand human-made satellites orbiting the earth and trying more or less successfully to avoid colliding with each other. So the sun also has a gravitational field and we’ve known the mathematics of gravitational fields since Newton. It’s the same formula for a star, a planet or whatever, all you need to know is its mass and its radius. And look at all the natural objects orbiting the sun without a problem. Can’t be that hard.
Canto: Okay… so how do we know the mass of the sun? Okay, forget it, let’s get back to exoplanets. What’s the big fuss here? Why are we so dead keen on exploring exoplanets?
Jacinta: Well the most obvious reason for the fuss is SETI, the search for extra-terrestrial intelligence, but to me it’s just satisfying a general curiosity, or you might say a many-faceted curiosity. And it’s all about us mostly. For example, is the solar system that we inhabit typical? We’ve mostly thought it was but we didn’t have anything to compare it with, but now we’re discovering all sorts of weird and wonderful planetary systems, and star systems, with gas giants like Jupiter orbiting incredibly close to their stars – it’s completely overturned our understanding of how planets exist and are formed, and that’s fantastically exciting.
Canto: So you say we discovered the first exoplanet about 20 years ago, and now we know about thousands – that’s a pretty huge expansion of our knowledge, so how come things have changed so fast? You’ve mentioned new technologies, new space probes, why have they suddenly become so successful?
Jacinta: Well I suppose it’s been a convergence of developments, but let’s go back to that first discovery, back in 1992. Two planets, the first ever discovered, were found orbiting a pulsar – a rapidly rotating neutron star. First discovery, first surprise. Pulsars with planets orbiting them, who would’ve thought? Pulsars are the remnants of supernovae – how could planets have survived that? But that first discovery was largely a consequence of our ability to measure, and the fact that pulsars pulse with extreme regularity. Any anomaly in the pulsing would be cause for further investigation, and that’s how the planets were found, and later independently confirmed. Now this was big news, in a field that was already becoming alert to the possibility of exoplanets, so you could say it opened the floodgates.
Canto: Really? But they didn’t discover any more for two or three years.
Jacinta: Well, okay it opened the gates but it didn’t start the flood, that really happened with the second discovery, the first discovery of a planet orbiting a main-sequence star like ours.
Canto: Main sequence? Please explain?
Jacinta: Well these are stars in a stable state, a state of balance or equilibrium, fusioning hydrogen – basically stars not too different from our own, within much the same range in terms of mass and luminosity. So 51 pegasus b was the first planet to be discovered by the radial velocity method, and radial velocity means the speed at which a star is moving towards or away from us. We can measure this, and whether the star is accelerating or decelerating in its movement, by means of the Doppler effect – waves bunch up when the object emitting them is moving towards us, they spread out when the object is receding from us, and the degree of the bunching or the spreading is a measure of their speed and whether it’s accelerating or decelerating. Now we can measure this with extreme accuracy using spectrometers, and that includes any perturbations in the star’s movement caused by orbiting bodies. That’s how 51 pegasus b was discovered.
Canto: So… how long have we had these spectrometers? Were they first developed in the nineties, or to the level of accuracy that they could detect these perturbations?
Jacinta: Well I don’t have a precise answer to that apart from the general observation that spectroscopes are getting better, and more carefully targeted for specific purposes. The French ELODIE spectrograph, for example, which was used to find 51 pegasus b, was first deployed in 1993 specifically for exoplanet searching, and since then it’s been replaced by another improved instrument, but of the same type. So it’s a kind of non-vicious circle, research leads to new technology which leads to new research and so on.
Canto: So – we’ve gotten very good at measuring perturbations in a star’s regular movements…
Jacinta: Regular perturbations.
Canto: And we know somehow that these are caused by planets orbiting around them? How do we know this?
Jacinta: Well we will know from the size of the perturbation and its regularity that it’s an orbiting body, and we know it’s not a star because it’s not emitting any light (though it may be a low-mass star whose light isn’t easily separated from its parent star). We also know – we knew from the results that it was a massive planet orbiting very close to its star – a hot Jupiter as they call it. And that was another surprise, but we’ve developed different techniques for discovering these things and we often use them to back each other up, to confirm or disconfirm previous findings. The ELODIE observation of 51 pegasus b was confirmed within a week of its announcement by another instrument, the Hamilton spectrograph in California. So there’s a lot of confirmation going on to weed out false positives.
Canto: So radial velocity is one technique, and obviously a very successful one as it got everyone excited about exoplanets, but what others are there, and which are the most successful and promising?
Jacinta: Well the radial velocity method was initially the most successful as you say, and hundreds of exoplanets have been discovered that way, but this method actually led to a kind of bias in the findings, because it was only able to detect perturbations above a certain level, so it was best for finding large planets close to their stars. But of course that was good too because we had never imagined that large gassy planets could exist so close to their stars. It’s opened up the whole field of planet formation. Then again, if the main aim is to find earth-like planets, this method is less effective than other methods. So let’s move on to the Kepler project. Kepler was launched in 2009, and since then you could say it has blitzed the field in terms of exoplanet detection. It uses transit photometry, which means that it measures the dimming of the light from a star when an orbiting planet passes between it and the Kepler detector.
Canto: So I get the idea of transit, as in the transit of venus, which we can see pretty clearly, but it’s amazing that we can detect transiting planets attached to stars so many light years away.
Jacinta: Well this is how we’ve expanded our world, from the infinitesimally small to the unfathomably large, from multiple billions of years to femtoseconds and beyond, through continuously refining technology, but let’s get back to Kepler. It orbits around the sun, and has collected data from around 145,000 main sequence stars in a fixed field of view – stars that are generally around the same distance from that dirty big black hole at the centre of our galaxy as our sun is.
Canto: Is that significant – that we’re focusing on stars in that range?
Jacinta: Apparently so, at least according to the Rare Earth Hypothesis, which puts all sorts of unimaginative limits on the likelihood of earth-like planets, IMHO, but no matter, it’s still a vast selection of stars, and we’ve reaped a grand harvest of planets from them – some 3000-odd, with over 1000 confirmed.
Canto: So… promising earth-like planets?
Jacinta: Yes, but I must point out that earth-like planets are difficult to detect. You see, Kepler was a kind of experiment, and we’ve learned from it, so that our next project will be much improved. For various reasons due to the photometric precision of the instrument, and inaccurate estimates of the variability of the stars in the field of view, we found that we needed to observe more transits to be sure we’d detected something. In other words we needed a longer mission than we’d planned for. And of course, Kepler has suffered serious technical problems, especially the failure of two reaction wheels, which have affected our ability to repoint the instrument. Having said that, we’ve been more than happy with its success.
Canto: Okay I just want to talk about these exoplanets. Can you summarise the most interesting discoveries?
Jacinta: Well, Kepler has certainly corrected the view we might’ve gotten from the earlier radial velocity method that large Jupiter-like planets are more common than smaller ones. We’ve had a number of reports from the Kepler group over the years, and over time they’ve adjusted downwards the average mass of the planets detected. And yes, they’ve discovered a number of planets in the ‘habzone’ as they call it. But that’s not all – only this year NASA confirmed the existence of five rocky planets, smaller than earth, orbiting a star that’s over 11 billion years old. I’m just trying to give you an idea of the explosion of findings, whether or not these planets contain life. And we’ve only just begun our hunt, and the refinement of instruments. It’s surely a great time to study astrophysics. It’s not just SETI, it’s about the incredible diversity of star systems, and working out where we fit into all this diversity.
Canto: Okay, I can see this an appropriately massive subject. Maybe we can revisit it from time to time?
Jacinta: Absolutely.
Some very useful sites:
http://www.planetary.org/explore/space-topics/exoplanets/
https://en.wikipedia.org/wiki/Kepler_(spacecraft)
how did life begin?: part 2 – RNA, panspermia, viroids and reviving the blob
Jacinta: So you’re going to talk about RNA, I know that stands for ribonucleic acid, and DNA is deoxy-ribonucleic acid, so – RNA is DNA without the oxygen?
Canto: Uhhh, you mean DNA is RNA without the oxygen.
Jacinta: Whatever, they’re big complex molecules aren’t they, but RNA is simpler, and less stable I think.
Canto: Okay, I’ll take it from here. We haven’t really known for very long that DNA is the essential material for coding and replicating life, and it’s a very complex molecule made up of four chemical bases, adenine, guanine, thymine and cytosine, better known as A, G, T and C. They connect to form base pairs, A always pairing with T and C with G.
Jacinta: What the hell are chemical bases? Do you mean bases as opposed to acids?
Canto: Well, yes. These bases, also called nucleobases, accept hydrogen ions, which have a positive charge. It’s all about pair bonding. The nucleobases – A, G, C and T, as well as uracil, found in RNA – are nitrogen-containing compounds which are attached to sugars… but let’s not get bogged down too much. The point is that DNA and RNA are nucleic acids that code for life, and most of the researchers chasing down the origin of life believe that RNA is a precursor of DNA in the process of replication.
Jacinta: And presumably there are precursors to RNA and so on.
Canto: Well presumably, but let’s just look at RNA, because we have a fair amount of evidence that this molecule preceded DNA as a ‘life-engine’, so to speak, and really no solid evidence, that I know of, of anything before RNA.
Jacinta: Okay so what is this evidence, and why did DNA take over?
Canto: Right, now the subject we’re entering into here is abiogenesis, the process by which life emerged from the inanimate. RNA is probably well down the chain from this emergence, but better to start with it than to dive into speculation. Now as you probably know, RNA has a single helical structure, and today it’s heavily involved in the process whereby DNA ‘creates’ proteins. In fact, all current life forms involve the action and interaction of three types of macromolecule, DNA, RNA and proteins…
Jacinta: But of course these complex molecules didn’t spring from nowhere.
Canto: Well we don’t know how they were built up, and many pundits think they may have been seeded here from elsewhere during the late heavy bombardment, which came to an end about 3.8 billion years ago, around the time that those Greenland rocks, with their heavy load of organic carbon, have been dated to. It seems plausible considering how quickly life seems to have taken off here.
Jacinta: Okay so tell us about RNA, how does it relate to the other two macromolecules?
Canto: Well, RNA is able to store genetic information, like DNA, and in fact it’s the genetic material for some of our scariest viruses, such as ebola, SARS, hep C, polio – not to mention influenza.
Jacinta: Wow, I didn’t know that. But one thing I do know about viruses is that they can’t exist independently of a host, so is RNA the basis of any truly independent life forms?
Canto: Not currently, on our planet, as far as we know, but the evidence is fairly strong that RNA has been central to life here from the very beginning, as it is still key to the most basic components of cells such as ribosomes, ATP and other co-enzymes. This suggests that RNA was once even more central, but in some areas it’s been subordinated to, and harnessed to, the more complex and recent DNA molecule. But, yes, since we can’t look at RNA coding for independent life-forms, we need to wind the clock back still further to look at precursors and other constituents of life, such as amino acids and peptides.
Jacinta: Which are chemical molecules, not biological ones. It seems to me we’re still a long way from working out the leap from chemistry to biology.
a peptide or amide bond – a covalent bond between two amino acid molecules
Canto: Yes, yes but we’re bridging various gaps. Peptides are created from amino acids, as you know. They are chains of amino acids linked by peptide bonds, and proteins are only distinguished from peptides in that they’re bigger versions of them, and bonded in a particular biologically useful way. You’ll notice when you read about this stuff that the terms ‘chemistry’ and ‘biology’ are used rather arbitrarily – a chemical compound can be referred to as a biological compound and vice versa. But various experiments have cast light on how increasingly ‘biological’ constituents are formed from simpler elements. For example, you may know that meteorites and comets, which bombarded the early earth in great numbers, contained plenty of amino acids – we’ve counted more than 70 different amino acids derived from meteorites, such as the Murchison meteorite that landed in Victoria in 1969. Another probable source of these amino acids, and even more complex and ‘biological’ molecules is comets, which also contain a lot of water in frozen form, but this has raised the question of how these molecules could have survived the impact of these colossal objects, which released enormous energy, some of them partially vaporising the earth’s crust. But an ingenious experiment, described in this video, and elsewhere, was able to simulate a comet’s impact, creating pressures many times greater than that experienced in our deepest oceans, to see what would happen to the amino acids. It was expected that they would barely survive the impact, but surprisingly they not only survived but forged bonds that created complex peptides.
a fragment of Murchison meteorite – of which there are many. This carbonaceous chondrite is still being analysed for organic compounds. Up to 70 amino acids identified so far
Jacinta: Mmmm, that is interesting. So, the gap between peptides, or proteins, and RNA, what do we know about that?
Canto: Well, now you’re getting into highly speculative territory, but it’s certainly worth speculating about. Firstly, though, in trying to solve this origin of life problem, we have to note that the earth’s atmosphere was incredibly different from what it is now. In fact it was probably quite different from the way Haldane and Oparin and later Miller and Urey envisaged it. It was predominantly carbon dioxide, with hydrogen sulphide, methane and other unpleasant gases – unpleasant to us, that is. That, together with the continual bombardment from outer space has led some scientists to suggest that the place to find the earliest life forms isn’t the open surface but in hidden nooks and crannies or deep underground, in more protected environments.
Jacinta: Yeah the discoveries of so-called extremophiles has made that idea fashionable, no doubt, but presumably these extremophiles are all DNA-based, so I don’t see how investigating them will answer my question.
Canto: Okay, so it’s back to RNA. The thing is, I don’t want to go into the properties of RNA here, it’s just too complicated.
Jacinta: I believe it was Richard Feynman who said something like ‘to fully understand a thing you have to build it’. So there’s still this leap from polypeptides or proteins, which don’t code for anything, they’re just built by ribosomes – RNA structures – from DNA instructions, to sophisticated coded replicators. We have no idea how DNA or RNA came into being, and nobody has successfully created life apart from Doktor Frankenstein. So it’s all a bit disappointing.
Canto: You must surely be joking, or just playing devil’s advocate. You know very well that this is an incredibly difficult nut to crack, and we’ve made huge progress, new discoveries are being made all the time in this field.
Jacinta: Okay, impress me.
Canto: Well, only this year NASA scientists have reported that the nucleobases uracil, thymine and cytosine, essential ingredients of DNA and RNA, have been created in the laboratory, from ingredients found only in outer space – for example pyramidine, which they’ve hypothesised was first created in giant red stars – and they’ve found pyrimidine in meteors. So, another step towards creating life, and further evidence that life here may have been seeded from elsewhere. And if that doesn’t impress you, what about viroids?
Jacinta: Uhhh… what are they, viral androids? Which reminds me, what about the artificial intelligence route to creating life? Intelligent life, what’s more exciting.
Canto: Another time. Viroids are described as ‘sub viral pathogens’. We were talking about viruses before, as a kind of halfway house between the living and the lifeless, but really they’re much more on the side of the living. The smallest known pathogenic virus is over 2000 nucleobases long, and the biggest – well, a megavirus was famously identified just last year and revived after being frozen in Siberian permafrost for something like 35,000 years…
Jacinta: An ancient megavirus has been revived…? WTF? Who thought that was a great idea? Wait a minute, the Siberian permafrost, wasn’t that where Steve MacQueen and his mates dropped The Blob? Megadeath, not just a shite band! We’re doomed!
Canto: Well, strictly speaking it’s a virion, a virus without a host, which means it’s in a kind of dormant phase, like a seed. But I don’t want to talk about megaviruses, fascinating though they are – and very new discoveries. I want to talk about viroids, which are plant pathogens. They consist of short strands of RNA, only a few hundred nucleases long, without the protein coat that characterises viruses, and their existence tends to support the ‘RNA world hypothesis’. It was the discoverer and namer of viroids, Theodor Diener, who pointed out that they were vitally important macromolecules for explaining essential steps in the evolution of life from inanimate matter. That was back in 1989, but his remarks were ignored, and only rediscovered in 2014. So viroids are now a big focus in abiogenesis. They’ve even been called living relics of the pre-cellular RNA world.
Jacinta: Okay, I’m more or less impressed. We’ll have to do more on abiogenesis in the future, it’s an intriguing topic, with more breakthroughs in the offing it seems. ..