Tag Archives: Gender and Sexual Orientation

Temperature and sex determination

Some interesting new research. The paper is, unfortunately, behind a paywall but they made a video, so it is worth posting.

Here’s the press release for the paper:

Scientists know that temperature determines sex in certain reptiles—alligators, lizards, turtles, and possibly dinosaurs. In many turtles, warm temperatures during incubation create females. Cold temperatures, males. But no one understands why.

A recent study sheds further light on this question. The findings of researchers Kayla Bieser, assistant professor at Northland College, and Thane Wibbels, professor of reproductive biology at the University of Alabama at Birmingham, will be published this month in the primary research journal “Sexual Development,” and is now available online.

This study represents the most comprehensive, simultaneous evaluation of the chronology of how sex-determining genes express themselves during embryonic development and and looks at the impacts of estrogen.

Bieser and Wibbels followed five different genes and what was going on in the exact same turtle. To date, scientists have looked at a number of turtles and pooled the data but Bieser is the first to follow individual turtles. She wanted to know when and how they “express” themselves. For an example, Bieser describes expression as the physical manifestation of those genes such as blue or brown eye color.

She looked at turtle eggs incubated at male and female temperatures and documented what the genes were doing while sex is being determined. “Which genes ‘turn on’ and when, could be an indication of what is triggering sex,” Bieser said.

According to Bieser, temperature-dependent sex determination species may be unable to evolve rapidly enough to offset the increases in temperature, which may ultimately result in their extinction.

“It’s critical that we understand the genetic mechanisms for which temperature acts and incorporate this knowledge into management plans for the conservation of these vulnerable species.”

Secondly, Bieser applied estrogen to eggs at a male-producing temperature. The purpose she said is to help determine the triggers for sex determination and how hormones, such as estrogen, can override the temperature signal.

In other words, would temperature or estrogen win out in deciding sex? The answer: in short, neither. What she found — and this is new information — is when estrogen is applied to eggs incubating at a male temperature, gonads—or sexual parts—do not develop. Or, if they do, they barely develop.

Why? “We don’t know yet,” Bieser said.

Scientists have been doing this experiment for some time but never reported these results. She suspects the reason is because scientists did not dissect the gonadal area specifically and that they took the general area but may have not analyzed the gonads to the same detailed level. In fact, this was a sticking point for one of the reviewers of this study—so Bieser provided photos of her findings.

“This research provides a critical understanding of how temperature acts on and above the genes in species where temperature determines sex—this is particularly critical in light of global climate change,” Bieser said.

Here’s the video:

The original paper:
Bieser K.L. · Wibbels T. 2014. Chronology, Magnitude and Duration of Expression of Putative Sex-Determining/Differentiation Genes in a Turtle with Temperature-Dependent Sex Determination. Sexual Development 8(6).

Is Human Behavior Genetic Or Learned?

Imagine that there is a trait observed among people that seems to occur more frequently in some families and not others. One might suspect that the trait is inherited genetically. Imagine researchers looking for the genetic underpinning of this trait and at first, not finding it. What might you conclude? It could be reasonable to conclude that the genetic underpinning of the trait is elusive, perhaps complicated with multiple genes, or that there is a non-genetic component, also not yet identified, that makes finding the genetic component harder. Eventually, you might assume, the gene will be found. Continue reading Is Human Behavior Genetic Or Learned?

Menz With Penz?

You’ve heard about Chicks with Bics. I decided to see if there was an equivilant for the guys, and there really isn’t. But these items did some up in a search:

Chicks with Bics?

The Bic Cristal For Her Ball Pen (which I would have named the Bic Cristal For Her Point Pen, but whatever) is a thing. These are pens for the ladies. It says:

BIC Cristal For Her has an elegant design – just for Her! It features a thin barrel designed to fit a women’s hand. It has a diamond engraved barrel for an elegant and unique feminine style.

Bic actually makes several feminine pens:

I recommend getting the assorted pack, and they you can try them all out and see how each one feels, and then if you settle on one that works really well for you, order that one on line in bulk to save money. Always carry a couple of the with you in case you want to write something.

Oh, and just in case you did’t know, the reviews on these products are a blast! Its a new internet meme.

Someone has answered my gentle prayers and FINALLY designed a pen that I can use all month long!…

Finally! For years I’ve had to rely on pencils, or at worst, a twig and some drops of my feminine blood to write down recipes …

I don’t know why they didn’t put a clearer warning on the label, they really should have because if you are a boy and use this pen you put yourself at great risk. My little brother turned into a unicorn…

See also Menz with Penz

Huxley: It is possible that he is a sissy

Huxley, imprisoned by Western heteronormative values.

Huxley is barely able to say the word “shoe,” does not yet know the word “pink,” has no clue what “gender” is, but last weekend somebody called him a sissy. He is not yet two years old.

This is interesting and it is a little complicated. And it involves multiple waves of offensive idiosity, so get ready for a longish story…
Continue reading Huxley: It is possible that he is a sissy

“…boys are innately better at math and science than girls…”

Sheril Kirshenbaum has a few comments about a piece in Science addressing innate differences between boys and girls in math. I have to say, it may be hard to accept the scientific truth sometimes, but the research really does consistently say the same thing again and again. In this latest study, the science …
Continue reading “…boys are innately better at math and science than girls…”

How Do You Get Sexual Orientation and Gender in Humans?

Humans appear to have a reasonable amount of diversity in their sexual orientations, 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 th is 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.

Continue reading How Do You Get Sexual Orientation and Gender in Humans?

Driving The Patriarchy: Demonic Males, Feminism, and Genetic Determinism

Behaviors are not caused by genes. There is not a gene that causes you to be good, or to be bad, or to be smart, or good at accounting, or to like bananas. There are, however, drives. “Drives” is a nicely vague term that we can all understand the meaning of. Thirst and hunger are drives we can all relate to. In fact, these drives are so basic, consistent and powerful that almost everyone has them, we share almost exact experiences in relation to them, and they can drive (as drives are wont to do) us to do extreme things when they are not met for long periods of time. While eating disorders are common enough and these affect a hunger drive, it is very rare to find a person thirst themselves to death.
Continue reading Driving The Patriarchy: Demonic Males, Feminism, and Genetic Determinism

Falsehoods: Human Universals

There 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.
Continue reading Falsehoods: Human Universals

Miss A and Miss W, Sexual Jealousy, and Julian Assange

Almost Diamonds has two interesting posts on the Julian Assange sexual assault/rape accusation/charges. I want to make a comment on part of the second post, but this may not make a lot of sense to you until you read both of them. They are concise and compelling so you will not regret the time you spend on them:
Continue reading Miss A and Miss W, Sexual Jealousy, and Julian Assange

What is the most important human adaptation?

Human 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 compared to apes. The actual sequence of development is not directly comparable: It is not the case that after a certain amount of time humans reach a specific stage reached earlier in the lifecycle by Chimpanzees, as the differences are more complicated than that. For the present purposes, we can characterize the human condition for early development like this: Human babies are more helpless in more ways and for longer than comparable ape babies.
Continue reading What is the most important human adaptation?

Why do women shop and men hunt?

Or, 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 with numerous little sub-arguments, and one about which I could write as many blog posts as I have fingers and toes, which means, at least twenty. (Apparently there was some pentaldactylsim in my ancestry, and I must admit that I’ll never really know what they cut off when I was born, if anything.)

Before going into this discussion I think it is wise, if against my nature, to tell you what the outcome will be: There is not a good argument to be found in the realm of behavioral biology for why American Women shop while their husbands sit on the bench in the mall outside the women’s fashion store fantasizing about a larger TV on which to watch the game. At the same time, there is a good argument to be made that men and women should have different hard wired behavioral proclivities, if there are any hard wired behavioral proclivities in our species. And, I’m afraid, the validity from an individual’s perspective of the various arguments that men and women are genetically programmed to be different (in ways that make biological sense) is normally determined by the background and politics of the observer and not the science. I am trained in behavioral biology, I was taught by the leading sociobiologists, I’ve carried out research in this area, and I was even present, somewhat admiringly, at the very birth of Evolutionary Psychology, in Room 14A in the Peabody Museum at Harvard, in the 1980s. So, if anyone is going to be a supporter of evolutionary psychology, it’s me.

But I’m not. Let me ‘splain….
Continue reading Why do women shop and men hunt?