Wednesday, March 18, 2020

Some Thoughts on Sex and Human Evolution

My father taught human evolution and cultural and physical anthropology, and he shared his passions with his kids, which influenced my own academic interest in neuroscience. Between his influence and my own training I have a decent understanding of how the human brain and body work and how radically our mating patterns and reproductive systems differ from even our closer relatives. And I do occasionally indulge in speculations about "evolutionary psychology" in order to help people understand how human sexuality got so messed up. However, I always acknowledge the uncertainties and the speculative quality of any such discussion of the peculiar origins of human sexuality.

I find the subject irresistible because human sexuality is weird. VERY weird! Most mammals have relatively consistent mating systems. They may have bizarre customs, but all members of a single species do pretty much the same things in roughly the same ways. But human mating systems are mixed up, messed up, and incredibly diverse.

To start with, we have by far the worst reproductive systems of all the mammals:

Maternal death rates: Without modern medicine we have the highest death rates in childbirth of any mammal, rivaled only by the hyena, and far higher than any other.

Menstruation: Other mammals can reabsorb a defective embryo with no fuss, but humans have a chorionic placenta that requires a complex menstrual cycle in order to flush out defective embryos. There is nothing nice and cuddly and natural about this. It is a uniquely debilitating and wasteful system. No other female mammals suffer from anything like it.

Extremely low conception rate: Most mammals have a conception rate of 90-99% per ovulation. Because of our bizarre menstrual cycle, we have a much lower conception rate than other mammals, around 15-20% per ovulation for fertile couples having regular sex, and less than 1% for a random act of intercourse. Women who are trying to conceive may require more than a dozen ovulations and hundreds of copulations to get pregnant, even if both partners are fertile and healthy.

In addition, our bodies seem designed to be confusing:

Cryptic ovulation: To complicate the conception problem, our ancestors evolved what is called "cryptic ovulation." Unlike any of our close primate relatives, there was no way people in prescientific societies could tell when a woman was fertile, so trying to conceive required frequent copulation throughout the cycle.

Full breasts on fertile and infertile females: Unlike any other female mammal, adult women have breasts that remain enlarged and prominent even when they are not pregnant or nursing. This hides yet another possible clue that a female is not fertile.

We also have a combination of rare mating patterns that together make us unique:

Nonreproductive sex: Humans, dolphins, and pigs seek out recreational sex. Bonobos use brief genital rubbing as a way to establish social ties and resolve tension. But most other mammals have zero interest in intercourse without the specific cue of a female who is ovulating and in heat.

Sexual frequency: One consequence of these evolutionary adaptations is that humans are incredibly oversexed by mammalian standards. Even in a monogamous marriage, a woman can easily have sex 10,000 times or more if both partners remain in good health, far more sex over a lifetime than other female mammals experience.

Social monogamy: Most mammals, including our closest cousins, are polygamous and opportunistic about sex; humans are in the small fraction, about 15%, of mammals that practice some kind of pair bonding and coparenting. Even in officially polygamous human societies, the vast majority of marriages involve only two people.

(Note: This is not to say that humans don't cheat on their spouses. As in other pair-bonding species, many individuals do stray if given the chance. Also, like many
monogamous species, humans often practice serial monogamy, changing partners after a period of exclusivity together.)

Extreme variation: Humans have THE most varied, conflicted, and confusing courtship rituals and mating systems in the animal kingdom. We may marvel at the peculiar things some non-human species do, but there is a great deal of consistency within each species. Among humans, different cultures set different rules for nearly every aspect of mate selection. Just the idea of a courtship process that sometimes takes minutes and sometimes takes months or years, would be inconceivable for other mammals.


Speculating about how we got so messed up is fun and can be illuminating, and I sometimes find it irresistible. So I'm no one to throw stones at someone else just because they do some "evo-devo" theorizing or make pop science points based on somewhat speculative neuroscience.

On the other hand, I'm in a good position to judge when people are stretching the research way too far and presenting wild claims and mere guesses as if they were facts. For a really good example of the difference between junk science and the responsible use of the existing research, see Sex at Dawn and Sex at Dusk. (Spoiler: Dawn is dishonest garbage; Dusk is a great read, meticulously honest, informative, and fun.)


Anyway, I hope this digression has piqued your curiosity about evolution and the weirdness of human sexuality. What strange, mixed-up creatures we are!

Saturday, March 31, 2018

The Dual Control Model of Sexual Arousal

I have talked in previous posts about the importance of thinking about both sexual arousal and sexual inhibition when dealing with libido differences. Because this is so important to understanding libido and sex drive, I want to come back to the subject and add some background and additional depth.

Most people first encounter this model by reading Emily Nagoski's excellent book, Come As You Are: The Surprising New Science that Will Transform Your Sex Life. Many readers will have also taken the Sexual Temperament Questionnaire, which is intended to help you understand where you fit in terms of the sensitivity of your "Sexual Excitation System" (SES) and the sensitivity of your "Sexual Inhibitory System" (SIS).

The SES/SIS questionnaire that Dr. Nagoski uses comes from what is known as the "Dual Control Model of Sexual Arousal." Because she teaches at Smith, a mostly-women's university, she uses a version of the questionnaire that is oriented somewhat more towards women. But the model and the SES/SIS questionnaire actually originated with research on men and their sexual problems.

Wednesday, January 31, 2018

For Girls & Women – First Time Masturbation Without a Vibe

This was an interesting question:

How can a woman masturbate and reach orgasm without sex toys?

This was my answer:

You don't need toys, but they do make it easier.  In most cases, the reason for not getting a vibrator or dildo is lack of privacy, but you can cope with that with a little bit of ingenuity.  

However, most women can manage without them.

Assuming you haven't done this before, here's a good twelve step program for learning how to have solo sex:

Sunday, December 31, 2017

Better Sex 101

This blog is mainly about tantric sex, and tantra is not for sexual novices.  However, I can remember reading things about sex when I was young that were way over my head, and I suspect that there may be a few other curious novices out there doing the same thing with this blog.

In addition, the comments and emails I receive tell me that there are many people who are fairly experienced, at least in terms of having had sex fairly often, who still don't know a lot of the basics of human anatomy and good sexual practices.

So I wanted to step back for a moment and create a guide to the basics, the kind of "sex ed" that young people need, but rarely get.

(Note: this guide was written for opposite-sex couples, but it should be fairly easy to adapt most things for same-sex couples and skip over the parts that are irrelevant.)

Thursday, November 30, 2017

How do I have sex for the first time with my husband on our wedding night?

I've been moving sex-related posts from other media over here whenever I have a chance. This post originated with a woman in the Middle East who was entering into an arranged marriage, and she had no idea what the wedding night would be like. I know this sounds strange to most Western readers, but it's a common problem for men and women in traditional cultures, particularly in India and in Muslim countries.

As an American girl, I've never experienced the sheer lack of knowledge about sex that is commonplace for traditional brides. But with my name and ancestry, I've been asked for advice many times in real life and online by virgin brides, and even some virgin grooms. Here's my attempt to demystify the big event for someone from a traditional culture:

Tuesday, October 31, 2017

Shakti's Guide to Good, Great, and Amazing Sex

 An old friend of mine did a really cool thing last month. She combed through the non-Tantra posts that I have scattered through this blog and organized them into what amounts to a sex ed handbook. Although she called it "A Beginner's Guide," it's really for anyone who wants to have better sex.

She goes by the name "TantraGirl" on Reddit, and this was her original post. It was a labor of love, and she has kindly granted permission for me to quote her. All of the comments from here down to the bar below were written by her:

Sunday, September 24, 2017

Orgasm and its Enemies: Karezza, Daoists, and other anti-orgasm crusaders

Every now and then, I get a barrage of messages from someone claiming that male ejaculation is bad, or that all orgasms are bad. Responding individually is time-consuming and unproductive, so I thought it would be worthwhile creating a general response. Perhaps this will help those of you who have run into these sorts of anti-orgasm fanatics.

Monday, July 31, 2017

How to learn to enjoy sex

For most people reading this blog, this is going to be an irrelevant question. But I was reminded today that it's a serious problem for some people whose bodies and minds have never quite gotten synched up to experience sex as something pleasurable.

The most common causes of 'sexual anhedonia' (lack of pleasure) are drugs and medications, hormonal problems, depression, dysthymia (a form of chronic depression), and religious repression. These require major lifestyle changes and/or serious medical or psychological treatment.

But what about the mysterious cases of anhedonia that don't seem to be related to any of these causes?

Friday, June 30, 2017

The Art of the Handjob

I'm continuing to collect things I wrote in other places that are relevant here. In this case, I was asked to explain what I mean by "giving a great handjob." (I'm going to describe giving one to a man, but the setup is similar and there's a link at the end to more detailed instructions for women.)

For starters, I strongly recommend three things:

Wednesday, May 31, 2017

Modern Buddhist Tantra

At the beginning of the main "how to learn tantric sex" part of this blog, I made some highly critical comments about the way religious tantra is being marketed in the West. Ninety-nine percent of it is a blatant scam, an attempt to sell a fake, cotton candy version of Tantrism using sex as bait to get people into a cult.

Most of the ideas that are being peddled by these scammers as "spiritual truths" can be traced back to 19th century European mysticism, not to Asian religions, and especially not to Tantra. Even some of the most basic elements, like chakras, were words borrowed from the East, given totally different meanings in the West, and then exported back to Asia in an unrecognizable form. But no matter what you have been told, Tantra is NOT just another flavor of Western mysticism in Eastern clothing.

Authentic mainstream Buddhism as practiced in Asia has never interested me. It is deeply ascetic and monastic, and I have no interest in renouncing the real physical world, stifling all pleasures and desires, or becoming a monk or nun. And the watered-down, sanitized form of Buddhism taught in the West has always struck me as passive and weak – a wimpy, artificially-neutered shadow of the real thing.

I am also severely prejudiced against the typical form of Tantrism currently practiced in India, the home of my ancestors. This is an embarrassingly sleazy form of fake witchcraft and sorcery that preys on poor people, with "tantric wizards" peddling useless charms and hexes and fake cures around the edges of Hindu temples.

And, until recently, I had not given Buddhist Tantra more than a glance, because it seemed to be filled with bizarre demons and spirits and a lot of the same magical nonsense as the Hindu version.

However, at the urging of several of my friends and tantric sex preceptors, I have recently been reading David Chapman's blog Vividness and a number of related sources. And Chapman has just about convinced me that the kind of tantric sex that I have been studying, practicing, and writing about CAN live comfortably within a modernized form of Buddhist Tantra.

Since I know some of the readers of this blog are looking for something more than "just" fantastic sex, I wanted to share some of Chapman's ideas about what a truly modernized form of Buddhist Tantra would look like.

For him, Tantra is not some tacky hedge wizard selling you amulets. Nor is it some goofy crystal-brained New Age guru selling you "sacred sex" on the installment plan. And it is definitely not an ascetic, life-denying way to achieve nirvana in some far-distant future. On the contrary, it is a muscular, no-nonsense application of a pragmatic problem-solving philosophy to effective action in this world.