human sexuality
gregladen | November 24, 2013Catching Fire is apparently a very popular book and/or movie that everyone is very excited about. But Catching Fire: How Cooking Made Us Human is a different a book about some interesting research I was involved in about the origin of our genus, Homo.
You can pick up a copy of our paper on this page. We call it "The Cooking Hypothesis." The basic idea can be summarized with these points:
1) Cooking food transformed human ecology. Many potential foods in the environment can't be consumed by humans (or apes in general) without cooking. But adding cooking to our species-specific technology,…
gregladen | April 10, 2013A study just published in the Proceedings of the National Academy of Sciences explores the question of penis size and female preference in humans. The study involved making a set of 3D models of human males of various relative body sizes, and fitting them out with various size flaccid penises. These were shown to a sample of Australian women to get their reactions.
The assumption of this study is that at some time in the past humans did not wear clothing, so that information about penis size in men would be available to women who could observe flaccid penises and then choose sexual…
gregladen | February 27, 2013Humans appear to have a great deal of variation in sexual orientation, in what is often referred to as "gender" and in adult behavior generally. When convenient, people will point to "genes" as the "cause" of any particular subset of this diversity (or all of it). When convenient, people will point to "culture" as the "cause" of ... whatever. The "real" story is more complicated, less clear, and very interesting. And, starting now, I promise to stop using so many "scare" quotes.
Fixed up and reposted.
Prior to birth there are a number of factors than can influence things like gender or…
gregladen | February 5, 2013Valentine’s Day is coming up, so it is time to think about kissing. Pursuant to this, Sheril Kirshenbaum, author of “The Science of Kissing,” has made the Kindle version of her excellent book available at a discounted price through February 18th. The book is here: The Science of Kissing: What Our Lips Are Telling Us. (Sheril is also the co-author of Unscientific America: How Scientific Illiteracy Threatens our Future.)
The Science of Kissing
Further details as well as a video (don’t worry, it’s work safe) are here, on Sheril’s site.
Also pursuant to Valentine’s Day, I thought it…
gregladen | December 3, 2012A study has just come out in the Journal of Sex Research comparing various psychological and lifestyle measures of women who act in pornographic films with matched sets of women who do not.
There is a pretty clear association between negative attitudes towards pornography and negative assessments of the quality of life for actresses in the pornography genre. Studies have shown that those who regarded pornography as harmful to society also believed that those acting in the films must not like their work. Studies have also shown that people tend to believe that porn stars have sexual and…
gregladen | November 14, 2012The Gender vs. Sex question...referring to the meaning of those two terms in relation to each other...is standard material for discussion in Anthropology and related fields, but is often left unattended to in day to day discourse. Both terms have internal complexity, with Gender meaning something about people’s identity as well as being a linguistic term, different but overlapping, and of course, Sex is a verby noun sometimes. But when we say “Gender vs. Sex” we are clearly talking about biological things such as chromosomes and genitalia, behavioral things such as attraction and orientation…
gregladen | January 26, 2011There are human universals. There, I said it. Now give me about a half hour to explain why this is both correct and a Falsehood. But first, some background and definition.
Most simply defined, a human universal is a trait, behavior or cultural feature that we find in all human societies. Men are always on average larger than women. All humans see the same exact range of colors because our eyes are the same. The range of emotions experienced by people is the same, and appears in facial expressions and other outward affect, in the same way across all humans.
The term "Human Universal"…
gregladen | October 22, 2010Human infants require more care than they should, if we form our expectations based on closely related species (apes, and more generally, Old World simian primates). It has been said that humans are born three months early. This is not accurate. It was thought that our body size predicted a 12 month gestation, and some suggested that Neanderthals would have had such, but this research conclusion has been set aside based on new analysis. But it is still true that developmentally, human children do not reach a stage of development that allows some degree of self care for a very long time…
gregladen | October 12, 2010Or, when the hunting season is closed, watch teh game (the guys), or when there are no sales, admire each other's shoes (the gals)?
This is, of course, a parody of the sociobiological, or in modern parlance, the "evolutionary psychology" argument linking behaviors that evolved in our species during the long slog known as The Pleistocene with today's behavior in the modern predator-free food-rich world. And, it is a very sound argument. If, by "sound" you mean "sounds good unless you listen really hard."
I list this argument among the falsehoods, but really, this is a category of argument…
gregladen | August 9, 2010From Skeptically Speaking:
We talk to author Christopher Ryan about his new book Sex at Dawn: The Prehistoric Origins of Modern Sexuality. We'll discuss the most recent science and theories, and how social norms compare to our biological impulses.
This Friday. Details here. I may have to read this book.
gregladen | January 3, 2010In a recent study, 56 percent of the women interviewed in a sample of 1800 claimed that they had a "g-spot" which is an area inside the vagina with increased sensitivity with respect to sexual arousal.
(Added: See THIS write up of the original research)
But a twin study showed that when one twin claimed whether or not to have a g-spot, the other twin did not make the same claim at the frequency one would expect if the g-spot was the expression of a genetic trait with straight forward Mendelian inheritance.
Therefore, the scientists conclude, the g-spot does not exist. At all.
How can this…
gregladen | June 30, 2009This post was originally titled "Mail Order Brides and Hypergyny." I was prompted to revisit the post because it received a a rather astonishing comment that I chose not to allow, but I did post it on my Facebook page where any attention it would receive would be from the thoughtful people that make up my Facebook community rather than just anybody out there on the Internet. Also, I recently received a complaint from a reader that Scienceblogs.com has been showing a lot of ads for "mail order brides," and this post was originally partly a response to that.
I should also mention that in the…
gregladen | May 16, 2009Sexual topics are largely taboo in China, so as a result, many people walk around not knowing what they really need to know about this important topic. Recognizing this problem, the Chinese Government has decided to build a huge, totally OTT sex theme park. Presumably all Chinese citizens will be required to go and enjoy this park.
China is building what is billed as its first sex theme park, aimed at improving both the sex education and the sex life of its visitors.
Due to open in Chongqing in October, Love Land will include displays of giant genitalia, naked bodies and an exhibition on…
gregladen | May 12, 2009According to a study just coming out in the Journal of Sexual Medicine, "variations in emotional intelligence--the ability to identify and manage emotions of one's self and others--are associated with orgasmic frequency during intercourse and masturbation."
In short, the study found:
Emotional intelligence was not associated with ... age and years of education, nor did we find a significant association between emotional intelligence and potential risk factors for [female orgasmic disorder] FOD such as age, body mass index, physical or sexual abuse, or menopause. We found emotional…
gregladen | April 28, 2009Gallup has taken on the task of explaining, in ultimate terms, the evolutionarily designed features of the human penis. He works this as an engineering problem from the perspective of evolutionary psychology, which is always a little bit dangerious, but gallup isn't quite the arm waiver that a lot of other EP's are, so he may be doing it right.
Gallup's work is written up an an all-too-sophomoric Scientific American article by Jesse Bering which just barely falls short of explaining this important biological phenomenon in terms of a pair of headlights, a flashlight, and a little red waagon.…
gregladen | March 6, 2009I'm starting to worry that the last few Friday Weird Science write-ups by Scicurious (who seems, these days, to be the primary blogger at Neurotopia) have been of papers that I happen to have read. Just so you know: Thousands of papers are published per week across the diverse sciences, and although Scicurious tends to deal with life science and I tend to read life science, the chances of this particular harmonic convergence across bloggers regarding papers published over the last decade is statistically almost zero. More likely, Scicurious and I just have similar taste ... or lack thereof…