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bonobos, humans, sex, kids, community and work: an interminable conversation 1

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just being cosy

 

Canto: We need to face the sex issue, which is such a problematic one for humans, and far less problematic, it seems, for bonobos.

Jacinta:Yes, they don’t need a Me Too movement, coz the males are already scared of them. I mean the boss females.

Canto: Well it’s not just the males hitting on the females. In bonobo societies, it’s males on males, females on females, old on young, kids on kids, but with a minimum of fuss and bother, it seems to me. And it’s not all the time, I don’t want to exaggerate anything. There are no nymphomaniacs, whatever that means.

Jacinta: A pejorative term. The male equivalents are called studs.

Canto: Well, not always. Sometimes called sex addicts. And paedophiles of course. Suitable cases for treatment. And I remember a group calling themselves ‘sluts on bikes’, seeking to retool the term for their own benefit somehow. I think there’s a lot of confusion or uncertainty out there, about whether an overdeveloped interest in sex is good or bad. And of course there’s a big issue about sexual victims, which doesn’t seem a problem for bonobos.

Jacinta: Not a major problem, but the females appear to keep the males in line, if they go too far. After all much of the sexual stuff is just mutual masturbation.

Canto: Yeah, nowadays, human males – and maybe females – get off on porn, or their own fantasies, wanking in the safe confines of their bedrooms, imagining touchy-feelies rather than experiencing them. It’s quite sad. Bonobos don’t have that problem.

Jacinta: It’s certainly true that there are plenty of sexually unsatisfied human apes around. But maybe if they weren’t so aware of sex – especially the hypersexuality of porn – they wouldn’t be so obsessed with what they’re missing out on. Take orangutans. They’re mostly isolated, and I doubt if they spend much time masturbating…

Canto: Ah but they do spend some time on it. If the Gizmodo website is to be trusted, masturbation has been observed in at least 80 types of male primates, and 50 types of female primates, including orangutans. And I don’t quite trust that male-female disparity.

Jacinta: Yes, that’s odd. And the point is that the crotch area is the most erogenous zone for all mammals, surely – and then some. And it doesn’t require fantasising about sexy other members of your species. Think of the first time you masturbated…

Canto: I really can’t recall the first time….

Jacinta: It’s highly likely you found your pubes rubbing against something, and it felt, well, stimulating, so you rubbed some more. Nothing directly to do with sex, for us or for other mammals. When a dog starts humping your leg, it’s not actually humping, or thinking of humping, presumably.

Canto: So it’s all about chemicals, fireworks in the brain, or something? A dog humps your leg because he’s excited, and humping gets him more excited. But it’s the old chicken and egg – does it start with the humping or the excitement?

Jacinta: Well I suppose the main point for us is that masturbation is natural and common for many species, given the evolution of erogenous zones, especially the zone associated with reproduction. But I’m more interested in another phenomenon – reproduction. In spite of their interest in sex, bonobo females are unable, it seems, to produce more than a few offspring in their lives. According to Wikipedia, the most offspring produced by a human female, that we know of, is 44, 43 of whom survived infancy. That’s a woman in Uganda, whose last child was born in 2016. There are recordings of greater numbers in previous centuries, but they’re insufficiently verified. And this woman, Mariam Nabatanzi, wasn’t just showing off, she had a rare condition that caused hyperovulation. Her births included 3 sets of quadruplets, 4 of triplets and 6 of twins, and she might’ve added to the number but a procedure she underwent in 2019, at age 40, put a stop to it all.

Canto: Elon Musk would’ve been proud of her.

Jacinta: Yeah, well, I wonder if he’s helping pay Ms Nabatanzi’s food bills, though hopefully her unwonted fame would help with that. It’s interesting that both Franz de Waal and Jane Goodall mention, in the beautifully photographed Deutsche Welle documentary referenced below, that the ability of humans to reproduce rapidly compared to other primates has been a vital factor in our dominance of the biosphere, with its positive and negative impacts. De Waal suggests that this high reproductive rate is somehow due to the family structure we’ve developed, with the father helping out the mother, not so much directly as indirectly, as material provider and support. But I think this claim needs more support or more fleshing out.

Canto: Yes, it seems to fly in the face of what we know about bonobo culture, where the mother seems to be helped out by other females, and males, in a tight-knit community. Or is this an exaggeration? I recall reading that this community care, or extended family care, occurs in corvids as well. I don’t know how many chicks the average crow gives birth to in a lifetime. Anyway, it seems that the long intervals between births in chimps and bonobos is more psychological, or cultural if you like, than physiological. The mothers do much of the caring and feeding, and it’s exhausting. Humans have bottle-feeding for instance, and anyone can be in charge of that. I did it for my little brother when I was a kid, and even learned to change nappies. Human mothers are sometimes back at work weeks or even days after giving birth.

Jacinta: Which would require other carers. Maybe we’re not so selfish as we think. But then again, in the WEIRD world we’re having fewer children, and as other regions become more well-off they’re having fewer children too.

Canto: Except for Elon Musk.

Jacinta: Crows generally lay a clutch of 2-7 eggs every nesting season – that’s one clutch every year. About 40 percent of all the corvid species are co-operative breeders, a much bigger percentage than other bird species. Crows’ lifespans can vary wildly – some can live for more than twenty years, and of course it’s hard to say how many offspring they produce in a lifetime, never mind how many of their chicks survive to adulthood. But returning to humans and bonobos, both species make a habit of having sex for fun, though with bonobos it’s more of a standard thing – they don’t have killjoy religious figures or ’empowered’ celibates spoiling the party.

Canto: We’re certainly a long way from public sex. Even nudist colonies now seem a distant memory, and they were about as sexy as an old fart’s farts.

Jacinta: Well, that’s a bit rough. We’re just so much more diverse than bonobos, you can’t compare. Everything from lifetime vows of celibacy to sex dungeons, about which I know nothing.

Canto: We’ll explore them, no doubt. But of course bonobos, when they’re not eating and sleeping, have a lot of time for play. They’re not trying to create the next exciting technology or to quantise gravity or to become the richest entrepreneur in the jungle or to take over their neighbours’ territory or whatever. All play, even sexual play, and no work can be a bit mind-numbing perhaps. A bit of your old Freudian sublimation isn’t such a bad thing.

Jacinta: How about getting AI to do all the smart stuff and we just play?

Canto: Ahh, now you’re talking about the future, beyond where we’ll be, unless those longevity diets really kick in…

References

https://gizmodo.com/9-animals-that-masturbate-other-than-humans-1723592357

https://en.wikipedia.org/wiki/List_of_people_with_the_most_children

 

Written by stewart henderson

July 27, 2022 at 8:48 pm

22 – sex, reproduction, science, bonobos

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the act, depicted by Leonardo, along with his intriguing mirror writing

Thinking on dolphins again, I remember reading claims about sophisticated dolphin language, at a vocal range beyond human hearing, and I’ve also read scientific dismissals of such claims. I’m thinking again about these questions (the communications of some birds also comes to mind) because the communicative complexity of language would have enabled human apes to, among other things, be species-aware of the connection between sex and reproduction – though unfortunately failures in that communication still result in unwanted teenage pregnancies. 

But I don’t seriously imagine that any other species – on this planet at least – knows that the joys of rump-pumpy lead to the much-later popping out of wee human replicants. For one thing, Matthew Cobb’s book The egg & sperm race provides an account of how confused we humans were, even at the time of Leonardo, about ‘the exact relationship between male, female and offspring’. They were particularly confused with regard to non-human generation. Ideas about barnacle geese being hatched from barnacles, mice being generated from wheat and vipers from dust were entertained at the highest level, even at the Royal Society in the 17th century. The spontaneous generation of the tiniest creatures was essentially a given for millennia. But human generation was also much of a mystery until relatively recently. Here’s a little summary from Cobb:

Although the real situation now appears obvious, discovering exactly what goes on was a long, complicated process. Even what might seem to be the most obvious step in generation – the link between sexual intercourse and pregnancy in humans – is really quite difficult to demonstrate. Part of the problem is that the clear signs of pregnancy do not immediately follow the sexual act. Even menstruation does not necessarily appear to be directly linked to pregnancy: although women stop menstruating when they are pregnant, some women always have irregular periods, while teenage girls can get pregnant without ever having menstruated. The link between sex and generation is so unobvious that in the 20th-century the Trobriand Islanders in the Pacific Ocean were said to be very surprised to learn that there is a connection between the two. All around the world, folktales of conception taking place in the most astonishing ways, such as by eating fruit (mango, lemon, apple, orange, peach ..), accidentally swallowing crane dung, or, more politically, being touched by the rays of a dragon.

The late 17th century, however, was the period in Europe when most of this confusion was cleared up, at least in the so-called developed world, thanks mainly to the work of four gifteded individuals, Francesco Redi (1626-97), Jan Swammerdam (1637-80), Nicolas Steno (1638-86) and Reinier de Graaf (1641-1673). Much of this work took place in the Netherlands, a major progressive and scientific nation in this period, backed by massive profits from the spice and slave trades. Of course another power of the period was England, and one of the most important figures in researching ‘generation’, as the problem of sorting out the reproductive process was then called, was William Harvey, famous mostly for working out the role of the heart in circulating the blood. Harvey was a pioneering experimentalist, and his approach to the issues was essentially correct, and quite revolutionary, but he lacked the necessary to work out the detail of generation. In particular, he lacked a microscope. His late work, de generatione animalium (1651), though mostly a restatement of Aristotelian doctrine, was inspirational in that he emphasised, through experiment, the importance of the egg in generation, regardless of species. Without a microscope, however, this claim couldn’t be fully verified. Microscopes, or magnifiers of various kinds, had been used since antiquity, but their full development came only after the invention of the telescope. Galileo built his own compound microscope in the 1620s but they remained largely a novelty until later in the 17th century, with the founding of scientific societies and academies, and the sharing of scientific experiments and tools. 

The four above-mentioned intellectuals (the word scientist didn’t gain currency until the nineteenth century) – one Italian and three Dutch – were friends, colleagues, and sometimes frenemies at a time when being first with scientific breakthroughs was even more important than during the covid19 era. There were no professional researchers of course, so you had to publish to get recognition and encourage patronage (and you often needed patronage to get published).

Francesco Redi, who combined a more rigorous experimentalism than was common at the time with the wit and urbanity that made him a mainstay at the court of Grand Duke Ferdinando II of Tuscany, to whom he acted as physician among other things, carried out careful research on insects which proved that they weren’t generated spontaneously in rotting foodstuff or anything else. His interest in the subject was inspired by Steno who had come to Tuscany from his studies in Leiden, via Paris, with a reputation as an expert in dissection and cutting-edge experimentation. Steno was in turn influenced by the greater mathematical rigour of the intellectuals at Ferdinando’s court. The two worked together on fossils and geology as well as animal anatomy. Steno was interested in the difference between viviparous and oviparous reproduction – that’s to say, between creatures who produce live young and those who lay eggs – and stumbled on a new, decisive insight, that female ‘testicles’, at the time believed to be internalised versions of male testicles, were in fact ovaries, a housing for the female’s eggs. This was an insight from observation, rather than experiment, but it was of course correct, and revolutionary.

Steno, Swammerdam and de Graaf had all met in Leiden where they engaged in their first adult studies (Leiden University in the mid 17th century had more student enrolments than Cambridge and was one of the most progressive learning institutes in Europe), and Steno and Swammerdam, being in the same year, became firm friends and collaborators there. After their Leiden studies, all three went to to France, a common destination for young Dutch intellectuals. Swammerdam and Steno were attracted there by an extraordinary French polymath, Melchisédech Thévenot, who had visited Leiden during their studies there, and who was head of a private academy in Paris, which eventually morphed into the Académie Royale des Sciences. 

But I’m getting bogged down in fascinating detail. Read Cobb’s The egg & sperm race for the story of how these individuals, and others, sorted out the story of ovaries, testes, semen and the equal contribution of males and females to offspring production. It’s a story of collaboration, rivalry and the struggle for both knowledge and recognition that captures much of scientific activity, then and now. 

The point of all this is to recognise how difficult it was for even the most complex species on the planet to work out the relationship between the pleasures of sex and the rather more mixed experience of childbirth – deadly for many, including my own grandmother. 

And yet, bonobos do it for pleasure and relief, openly, and manage to avoid having endless pregnancies, unlike  Anne Stuart, queen of Great Britain (18 pregnancies, none surviving to adulthood) and Maria Theresia, empress of Austria, and many other regions (16 pregnancies, only 3 of whom died in infancy), not to mention a horde of less ’eminent’ catholic martyrs to the world’s peopling. Bonobos have between five and seven infants, on average, in a lifetime, which is certainly more than enough. I’m not sure of the survival rate of offspring, but it would probably be higher if not for human depradations. 

References

Matthew Cobb, The egg & sperm race 

https://en.wikipedia.org/wiki/Melchisédech_Thévenot

https://www.britannica.com/animal/bonobo

Written by stewart henderson

January 18, 2021 at 7:18 pm