This is a response to Vol 5 Holly 4 ("Those Pesky Things!")...
My goodness, I'm sorry I brought the whole subject up in the first place. What interested me about the article in Science News was the link between hormones and intellectual function. The same hormones that affect women (and men!) in their daily lives have a profound and little-understood effect in the womb.
Anyway, as per Robert's whimsical comments I should reiterate that the authors of this study, both women, stated that it was not at all feasible to assign office tasks on the basis of monthly cycles. They pointed out that these are statistical truths and that every woman is different, and that men have hormonal cycles too.
Although I cannot claim any personal experience in these matters, I have known women on both ends of the scale and what Holly says is true. Some hardly notice the effects, but for others: YOW! The effects can be dramatic and even rather serious.
And now for another tidbit from the pages of Science News. Scientists have discovered some catepillar-like critter that ends up looking exactly like the stuff it eats. If it eats a certain flower called catkin, it ends up looking so much like catkin that it's virtually impossible to distinguish it from the real thing (in fact the biologist who discovered it almost fell out of a tree when he saw a piece of catkin moving!). And if the little bugger eats twigs it ends up looking like a twig! (Those are the only two shapes in its repertoire).
This bizarre miracle is controlled by plant chemicals called tannins. What fascinates me about both the hormones and the catepillars is the powerful effects that subtle differences in chemistry produce in growing things. A little too much substance X in the soup and your tiger sprouts polka dots! And as a programmer I see that behavior is just another kind of shape. If a little tannin can turn a catkin into a twig, who knows what a little estrogen will do?