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Actually, three more things before I give up for the night. As if there isn't enough to read out there, here are some interesting links from the blog roll.
First up is University of Minnesota Associate Professor P.Z. Myers on a fascinating topic, why women menstruate.
A new paper by Emera, Romero, and Wagner suggests an interesting new idea. They turn the question around: menstruation isn’t the phenomenon to be explained, decidualization, the production of a thickened endometrial lining, is the key process.And no, it's not because it's fun. That's a different topic.
All mammals prepare a specialized membrane for embryo implantation, the difference is that most mammals exhibit triggered decidualization, where the fertilized embryo itself instigates the thickening, while most primates have spontaneous decidualization (SD), which occurs even in the absence of a fertilized embryo. You can, for instance, induce menstruation in mice. By scratching the mouse endometrium, they will go through a pseudopregnancy and build up a thickened endometrial lining that will be shed when progesterone levels drop. So the reason mice don’t menstruate isn’t that they lack a mechanism for shedding the endometrial lining…it’s that they don’t build it up in the first place unless they’re actually going to use it.
So the question is, why do humans have spontaneous decidualization?
The answer that Emera suggests is entirely evolutionary, and involves maternal-fetal conflict. The mother and fetus have an adversarial relationship: mom’s best interest is to survive pregnancy to bear children again, and so her body tries to conserve resources for the long haul. The fetus, on the other hand, benefits from wresting as much from mom as it can, sometimes to the mother’s detriment. The fetus, for instance, manipulates the mother’s hormones to weaken the insulin response, so less sugar is taken up by mom’s cells, making more available for the fetus.
Why Do Women Menstruate?
There's lots more, of course, including a cladogram with lots of funny-sounding names on it ("Llama Glama" is my personal favorite), but that's the gist of it. This gets back to a discussion I had a couple of weeks ago at Paul Sunstone's blog, on an article about why horses have manes. I said, mostly correctly I think, that animals do not evolve or keep features they don't have a use for. It's not worth the energy and materials (food) needed to create them.
The thinking about menstruation goes along those lines. With that little added notion, it's worth a read, I think, to understand a bit about how evolution changes us.
The second bit is more typical fare for this blog, an article by Robert Reich on the current state of the Republican Party, and how it got there. It's pretty true, I think. The only thing I think it's important to add is that the Tea Party, while it went about it much differently, was another reaction to the unresponsiveness of our political institutions, particularly at the federal level like the Occupy movements have been. The Tea Partiers, though, tend to be authoritarians who believe in individual profit, whereas the Occupy folks tend to take the view that if the community is better off, so are we all. Neither is true or right under all circumstances, but I'm usually more in agreement with the Occupy folks. Communities can help themselves, individuals can't always.
Those are important points, because when you understand them it's much easier to see why the Tea Party was quickly subordinated by the Republican Party and Occupy movements have refused to be co-opted by the Democratic Party. I don't think it's because the Occupy folks are stronger, nor do I think they are necessarily smarter. They're just more committed to collective action. They make their decisions in assemblies, sometimes by unanimous consent only, others by a supermajority. That can be unwieldy, of course, but when they do make a decision it's a lot more likely that they will all be committed to it. Since these movements exist in large measure due to the failure of the Democratic Party and traditional progressive institutions, the relationship between them is likely to be arm's length at best.
The third is an article that James Ala wrote a couple of days ago at his place:
A crime was committed this week. It was murder most foul. Some might call it a mercy killing, the victim was barely alive after all, but this ignores how the victim was starved, beaten, and abused over the course of a decade.Like Reich's article, it's a good review of how we got to this sorry state of affairs, this time that state of affairs being the demise of what was once a promising experiment in self-government. Think of it as an expansion on this article that I wrote three weeks ago. It's actually a lot more than that, but you can think of it that way anyhow, because if I had the heart to contemplate the subject long enough, I would have written something similar.
The murder was quite nefarious and performed by a cabal of bad actors. The conspirators had a long history of malice towards the victim and had laid their plans long before the actual act.
At first the attack was focused on the Forth Amendment. The cabal used all matter of devious, incremental means to chip away at the protections of the Forth. Most useful in that chipping away was the “War On Drugs.”
The Slow Death Of Civil Liberties.
There, that should keep you for awhile.
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