About book Why Is Sex Fun? The Evolution Of Human Sexuality (1998)
Jared Diamond e’ un fisiologo. Il libro affronta alcuni aspetti della sessualita’ umana (tendenza monogamica, ovulazione non manifesta, ruolo del maschio nella famiglia, menopausa, segnali sessuali) dal punto di vista della biologia evoluzionistica, ma pescando abbondantemente nella fisiologia e nell’antropologia. Il risultato e’ a mio parere una certa mancanza di rigore, poiche’ l’A. apporta a sostegno delle proprie tesi evoluzioniste ora la biologia, ora l’antropologia, ora la fisiologia, secondo quale soccorra meglio, rendendo l’opera un pot-pourri poco strutturato e poco approfondito. In particolare, l’etnoantropologia esula dall’evoluzionismo, riferendosi ad un animale i cui comportamenti possono travalicare le limitazioni biologiche e superare i vincoli della selezione naturale (e non e’ intesa a dare conto delle evoluzioni biologiche, se non altro per i vari vincoli evolutivi tra i quali il problema del time-lag: l’evoluzione – che procede in tempi lunghissimi - rappresenta l’adattamento ad ere passate, non necessariamente identiche a quelle presenti). Nell’assumere il gene come unita’ di selezione l’A. sembra rifarsi a Dawkins, le cui tesi sono richiamate in diversi punti (pur senza nominarne l’autore), salvo disapplicarne le teorie in diversi punti. Accetta espressamente il determinismo genetico nella formazione di predisposizioni comportamentali, salvo poi ignorarne spesso la rilevanza, privilegiando valutazioni antropologiche. Alcuni brani sembrano presi pari pari da Dawkins, che peraltro non viene mai citato (il che ha irritato il mio amore sviscerato per questo Autore). Per quanto interessante, il libro risulta piu’ ambizioso che convincente.Divagazioni: Relativamente all’avvincente questione della comparsa dell’ovulazione non manifesta nella femmina umana, JD ragiona in termini evoluzionisti classici, domandandosi quale sia il vantaggio della mutazione per l’organismo, anziche’ pensare in termini di gene. Si avvale degli studi di R. Alexander e K. Noonan e di B. Sillén-Tullberg e A. Møller per avallare la tesi che il vantaggio sia costituito dall’incentivazione alla costituzione di un rapporto di coppia stabile. In se’ il ragionamento non fa una grinza, ma non puo’ risolvere il problema se sia nato prima l’uovo o la gallina, portando all’unica conclusione possibile (non esplicitata) che si sia determinato ad un certo punto una situazione di equilibrio in cui la crescente complessita’ del neonato rendeva non ancora necessario (altrimenti si incorre nel rischio di estinzione) ma certamente determinante per le probabilita’ di sopravvivenza della progenie il coinvolgimento paterno nelle cure parentali. Esattamente in questo stadio di sviluppo si sarebbe quindi dovuta manifestare la mutazione che comporta la scomparsa dei (necessariamente gia’ labili) segni esteriori dell’ovulazione, contribuendo alla formazione del legame stabile di coppia (altrimenti, in un diverso equilibrio, per il padre sarebbe stato piu’ conveniente utilizzare le proprie energie per fecondare altre femmine, anziche’ prestare sostegno alla prole). Ragionando in termini di individuo, quindi, secondo JD il maschio si sarebbe a quel punto convinto che conveniva – per avere la certezza della paternita’- instaurare un legame duraturo ed in linea di principio esclusivo. Ora, un Homo sapiens puo’ pensare cosi’ (ed e’ compito dell’antropologia indagare), ma l’antenato ominide non poteva certamente (non avrebbe neanche compreso il rapporto di causa ed effetto tra copulazione e procreazione, figuriamoci valutare razionalmente le conseguenze dell’assenza di segni esteriori dell’ovulazione in termini di certezza di paternita’!). Il meccanismo genetico e’ ben diverso: deve essersi sviluppato un gene che induceva il maschio ad assicurare cure parentali. Se si ragiona in questi termini, il momento in cui tale mutazione sia avvenuta e’ irrilevante, in quanto a qualsiasi stadio di complessita’ dell’organismo essa si sia presentata, questa avrebbe conseguito un vantaggio alla progenie (statisticamente probabile portatrice – o sicuramente portatrice se la variazione avviene nel cromosoma y, come ben possibile - del gene specifico) in termini di accresciute possibilita’ di sopravvivenza (vantaggio maggiore o minore in dipendenza dello stadio di sviluppo della complessita’). Diventa quindi irrilevante domandarsi se la mutazione ormonale femminile sia conseguenza o causa della cura parentale paterna, necessaria per l’affermazione dell’organismo piu’ complesso. Le due mutazioni possono essere avvenute (rectius: sono certamente avvenute) indipendentemente l’una dall’altra, anche se l’ipotesi piu’ convincente resta quella che la mutazione ormonale femminile sia stata successiva (in quanto la presenza di una tendenza paterna ad accudire la prole l’avrebbe avvantaggiata maggiormente). La valutazione di JD, invece, non prendendo in considerazione la mutazione genetica nel padre, il cui comportamento viene ritenuto una mera conseguenza della mutazione ormonale nella madre, presuppone una “fortunata coincidenza” della mutazione genetica casuale che comporta la perdita di segni esteriori dell’ovulazione con l’esatto stadio di sviluppo della complessita’ dell’organismo che l’avrebbe resa (non necessaria ma) opportuna! Alternativamente, si puo’ pensare ad un meccanismo del tipo “fenotipo esteso”, in cui la mutazione ormonale femminile (intervenuta a qualsiasi stadio di complessita’ dell’organismo) comporta una mutazione comportamentale maschile (tramite magari l’emissione di ferormoni piu’ “potenti”). Tale versione dei fatti (compatibile con il ragionamento di JD), presuppone peraltro una mutazione singola che comporta due effetti vantaggiosi. Non impossibile e neanche inverosimile, ma personalmente propendo per un’applicazione particolarmente rigorosa del rasoio di Occam. In presenza di una tendenza paterna ad accudire la prole, la mutazione casuale che comporta la perdita di (gia’ tenui) segnali esterni dell’ovulazione verrebbe certamente selezionata.Il ruolo del maschio viene affrontato da un punto di vista esclusivamente etnoantropologico, riferito quindi al presente, mentre l’evoluzione di certe caratteristiche maschili rappresentano il portato di situazioni non piu’ attuali. L’innegabile lotta tra i sessi andrebbe meglio inquadrata nell’ESS di John Maynard Smith e nel vantaggio genetico, anziche’ in quello individuale. Del resto, lo status del maschio delle societa’ umane (e non solo in quelle umane) ha un’incidenza diretta sulla fitness riproduttiva. Sarebbe preferibile un modello matematico basato sulla teoria dei giochi, l’ESS e la predisposizione genetica.Non mi convince l’asserita rilevanza nella lotta tra i sessi dell’investimento parentale squilibrato nell’embrione, che mi sembra sia solo mediata - in rapporto all’ESS - e non tenga conto della Concorde Fallacy. La quale non puo’ peraltro essere esclusa, ma “cosa fatta capo ha”, il che – negli ovipari - rende piu’ rilevante la strategia successiva alla deposizione, rispetto al calcolo delle energie spese. Quest’ultimo mi sembra rilevi esclusivamente nel senso di diminuire le possibilita’ di trasmettere i geni che inducono al comportamento poco “materno”, nel quadro del raggiungimento di un’ESS. Anche nei mammiferi, mi sembra, la durata della gestazione e dell’infanzia influiscono solo indirettamente nella definizione dei ruoli paterno e materno, nella misura (rilevante, senza dubbio) in cui incidono sulla definizione dell’ESS. Dettagli, sfumature, ma che indicano una certa mancanza di rigore.Sulle ragioni evolutive della menopausa, JD ripete quanto gia’ affermato altrove (il terzo scimpanze’), dilungandosi piuttosto inutilmente.Estremamente superficiale il capitolo sui segnali sessuali (un solo esempio: cosa significa “una bella faccia”, sia in senso etnoantropologico sia in senso biologico-evoutivo?). L’interazione e l’interferenza tra replicazione genetica e replicazione memica (aspetto per me affascinante, anche per i disastri provocati dall’asincronia dell’evoluzione dei due fenomeni) e’ appena accennata.
While sort of dating somebody that was very, very ill suited for me...so much that I was absolutely certain that we had no future, he would never be introduced to my family, et cetera et cetera, I really started being interested in the subject of sex. Attraction. The difference between women and men's approaches to it, the difference between pure physical attraction and what people call "chemistry." Pure, simple sexual attraction and then the kind of attraction that develops. While ultimately I didn't place much stock in the relationship, the undercurrent of sexual tension that buzzed between us was undeniable. I would find myself gazing at him in total awe, body abuzz. And then I'd wonder... why? Sure, I'd found him gorgeous at first sight but it was being in each others company that had done it, now my feelings/opinions had multiplied and it seemed like there had never been anybody MORE gorgeous. the first time he reached for my hand I was buzzin. And I couldn't make sense of it, it was totally out of my hands. Whether or not I wished to be attracted to him this way, I was. Of course I am a human being and with my evolved brain am able to grasp the weight of my choices and their consequences so I am not a slave to my body, but it was my body's reaction that piqued my interest. Like why this person? I'd been around beautiful men plenty, men technically more beautiful than he, why so enamored with this one? And so I've picked up a few books on sex, this one being the 2nd I've read, Bonk by Mary Roach the 1st. So, the fact that I had been looking to learn about something that was kind of specific, this book was a little bit of a let down. But only in the sense that there wasn't enough info on what I wanted to know. Sure, there was a brief mentioning of pheromones and how they are potentially responsible for the "chemistry" thing. I guess I wanted them to be a little more specific, like explain what's happening.. draw me a diagram of the route these pheromones take thru me, the synapses and nerves, the brain waves and activity. Maybe I'm just crazy for wanting an explanation for my attractions! There was a lot of random educational info, stuff I am less inclined to care about like the sex lives of animals and the anomalies and rarities that exist in them. An entire one out of the 6 chapters in the book is devoted to animal sex actually, including gems like listing other animals that enjoy sex, others that partake in same sex sex, others that have sex in private like humans instead of out in the open. There was a chapter on menopause (which according to this book is something that happens only to human females.) A chapter on breast feeding and the supposed non-evolution of male lactation, A chapter on gender roles in sex, yadda yadda. It's all interesting enough to read about, but that's because SEX in general is interesting to read about. I still prefer this book to Mary Roach's Bonk because it reported facts in an interesting and witty way without laying on the lame jokes so heavily and "breaking the fourth wall" constantly the way Roach does. Also Mary Roach isn't a Dr. or professor on the subject, or any subject, which causes me to mistrust a little more. Jared Diamond (who also wrote Guns, Germs, and Steel) is both a Dr. and Professor of human sexuality. That lends him a little more credibility in my eyes, and it shows in his writing which isn't amateurish the way Roach's is.SO. For anyone looking for a quick and interesting read, sort of random facts about sex/human sexuality this shouldn't disappoint. It's short, and mostly interesting... and written in a manner that an average person can enjoy it. You don't have to be a dr or a scientist to understand it, is what I mean. Tho, it won't explain to you why you just can't seem to get enough of your new gf/bf, or why the sex with your plain jane neighbor is soo much more amazing than with your smoking hot ex. Or why you aren't attracted to Mr. Perfect with the body like a greek god, and yet you are borderline obsessive about the cute cater waiter from last night's dinner. I have two more books on the subject but something tells me that searching for an explanation of my attraction to a man is like searching for the meaning in life...destined to be fruitless forever... but at least reading about sex is never dull ;)
Do You like book Why Is Sex Fun? The Evolution Of Human Sexuality (1998)?
Thought-provoking across the board and convincing in some places, Diamond makes a evolutionary biology argument that posits part of human distinctiveness arises from our unusual reproductive characteristics: concealed ovulation, recreational sex, and female menopause. Diamond's meditations on how menopause may have been selected for and why men don't breastfeed their children were compelling and carefully argued. When he ventured into the territory of human social arrangements; however, Diamond hamstrung himself with his own disciplinary bias. As a sociologist, I find it extremely hard to believe that complex human social behaviors - like adornment and marital relationships - are driven by an evolutionary logic. As Diamond points out in his chapter on male breastfeeding, humans have often made "counter-evolutionary" choices. If our instincts drive us to behave in certain ways - why some ways but not others? I highly recommend the book, despite these problems.
—Alison Buck
Why is sex fun? Who the eff cares??? It just IS...if you're doing it right, that is. Ha!I thought the book had a lot of promise, but it failed to deliver on many, many levels. Diamond's lack of footnotes really irked me and I was left questioning a lot of his research. I mean sure, learning about the number of hermaphroditic fashion models really boosted my self-esteem, but hello? Source please! I don't have time to go digging around through his entire bibliography looking for relevance. Ultimately, I learned a lot about animals and very little about humans. C'est la vie.
—Charity
3.5 starsI must admit that I would never have picked this book up if I hadn't come to know of Jared Diamond's brilliant writing in his other book: Guns, Germs and Steel. Although human sexuality is an endlessly fascinating topic, books attempting to scrutinize it are all too often filled with nothing more than bumbling rhetorical questions and weird, irrelevant anecdotes. So knowing how amazing Guns, Germs and Steel was, I was fairly confident Jared Diamond would not disappoint in Why Is Sex Fun?My final thoughts: Why Is Sex Fun? is a worthwhile read that is well-structured and answers questions methodically. Among many other things, this book informs me about many new things on human sexuality (of course) and even poses questions I admittedly never thought of asking before. But unlike in GGS, the explanations put forward in Why is Sex Fun? still overwhelmingly feel like theories. The reason why I loved GGS so much is that the explanation Diamond provided us with were so well-rounded and consistent I could easily accept it as 'truth' (albeit not perfectly complete, but then, what theory actually is). So although the theories in WISF are plausible, they fail to consider so many aspects and fail to explain so many observations that it doesn't really convince the readers.---For a quick recap, here are the questions the book addressed:1. Why don't men lactate?2. What is the purpose of recreational sex?3. Why did we evolve concealed ovulation?4. What are the roles of men?5. Why did we evolve the female menopause?6. Body signals. (why do men have large penises?)---And here are a few questions and observations that I thought need addressing:1. It is said that "recreational sex is the glue holding a human couple together while they rear their helpless baby together". Well, I'm sure many of you (like myself) would have raised their eyebrows at this. Is sex really the only reason a male would stay with his mate? And if he is so inclined to leave, would sex really be so important that he decides to stay after all? If deserting his mate is evolutionarily better for the male, then why didn't males evolve behavior that causes them to leave their mates despite the promise of sex?Besides, it's still evolutionary more advantageous for the male to cheat on his mate, and there's no physical inhibition stopping him from doing so. He could still be monogamous and profit from regular sex with his mate AND occasionally cheat on her but not so much that he would be jeopardizing his child's life by neglect. 2. Why do female mammals tend to be smaller in size than males? As pointed out in the book, most of the time it is the females that have to care for the young. So wouldn't it be more logical if females were bigger than males? They would be better prepared to chase away predators and protect their young, and they would also be more prepared to chase away competing mothers for the best food sources. I get it that males have to be big in order to compete with each other for females, but it doesn't necessarily mean that they have to be bigger than females. So why are females smaller?3. What exactly are the advantages of monogamy? The book often used monogamy as part of an explanation, but it never addressed the reasons why some animal species including humans are monogamous in the first place. From my point of view, monogamy isn't even strictly necessary in traditional hunter-gatherer societies. The child could be taken care of by the whole tribe, as opposed to just the father (as the book points out why monogamy is necessary). 4. Now, I'm almost certain that this particular question had been in most of your minds while reading through the book: What is the the advantage of the female orgasm? And additionally, the book didn't really answer its title question: Why exactly is sex fun? The only answers the book provided were a) Recreational sex is important to conserve monogamy b) recreational sex is a by-product of concealed ovulation which is also important to ensure monogamyWell, okay. But the book didn't go any deeper than that and ask the question why sex is fun in the first place, or why sex has to feel good.5. In the book it was mentioned that there are two types of males, the "show off" and the "provider". It was also mentioned that females are better of married to the "provider" but that it's better for the male to be the "show off" because he attracts more females. So, why are females attracted to the "show off" instead of being genetically programmed to be more attracted to the "provider"?----Well, that's that.
—Irene
