Here's a picture to make you feel relatively fortunate, from the April 2007 issue of Natural History:
Naked mole rats are odd little mammals in which only the queen of the colony gets to breed. The point of this picture is that even when not near the end of their term of pregnancy, they are recognizably distinct from other rats in the colony — they tend to be much longer. The reason is that the hormones during pregnancy, and probably also the physical stresses on their body, induces the lumbar vertebrae to actually grow longer. Humans, fortunately, do not grow a couple of inches vertically with each child.
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These mole rats repress breeding in other members of the colony by forcing them to eat feces laced with birth control chemicals.
Also, they are diploid, so do not have the added kin-selection r-values of the haplodipolid bees/ants/wasps ... but since they are son inbred, it turns out that an individual female is more closely related to her potential sisters than to her potential offspring. Thus she is more willing to help her mother raise more sisters.
But most important of all, they eat a lot of ROOTS, and they have the same physical morphology as the robust Australopiths, who also (I believe) at a lot of roots. So nake mole rats (and other mole rats) are an excellent model for a key moment in human evolutionary history ... the adoption of Plant Underground Storage Organs as a fallback food.
(Sorry, I get excited about naked mole rats)
"Son inbred"???? Wow, that was quite a Freudian Typo ..... but since it could be correct I'm not going to suggest it be changed...
"Humans, fortunately, do not grow a couple of inches vertically with each child."
Unfortunatly, I LOST some height with each child...but my feet got bigger.
I wouldn't have minded so much gaining a little height. :-)
How long do the size increases last? Is the new bone permanent or does it leach away like osteoporosis when the hormone levels revert to normal? If it's permanent, that would imply that older queens tend to be longer, no?
The reason is that the hormones during pregnancy, and probably also the physical stresses on their body, induces the lumbar vertebrae to actually grow longer. Humans, fortunately, do not grow a couple of inches vertically with each child.
Vertical inches, no. Cup sizes, yes.
"they have the same physical morphology as the robust Australopiths"
uh...huh?
Yeah, but do you have a naked mole rat T-shirt? Or plush toy?
I'd vote for getting a couple of inches taller with each pregnancy, myself. Being short often sucks.
More like unnatural history.
Zing.
Ouch.
If that french feminist (can't remember her name) ever fulfill her dream of medical technology enabling gestation inside males willing to experience it ... I'm no longer willing. It's my body and I say NO. :-)
I'm thinking I probably shouldn't show that pic to my pregnant officemate, here.
Actually, that would be kind of cool if women gained a couple inches with their first pregnancy, and maybe one more with the second. That would create an interesting social dynamic, with height being used amongst women as some sort of seniority system. Not that this would be good, but I think that's what we'd see.
Now what would be weird is if humans had the same kind of social system where only the "queen" gets to breed.
CCP: I made the mistake of summarizing years of research (by me and my colleagues) in a phrase.
The physical morphology is all in the head .... some would say my head, but I contend in the hominid (and rat) head. There seems to be a set of features that emerge when consumption of USO's is important, having to do mainly with the fact that USOs are digested in the mouth to a much greater degree than in the gut, as well as their toughness, etc.
Of course, the rodents are tiny so you need to use a magnifying glass....
Oh, what I wouldn't give to have gained a couple of inches with each pregnancy! To actually be able to change lightbulbs without a ladder, buy groceries without climbing up the shelves. . .
Inoculated Mind, while tallness in women who've had multiple children might not be a mark of status, it sure would make it easier to pick out the quiverfull moms.
And they return to their normal size once the human female stops breastfeeding. But, it was fun while it lasted.
(Not that I am a male chauvinist sexist pig, or anything. Some of my best lovers had flat chests.)
Uh, my wife was a C before she got pregnant. She grew to probably an E or an F while breastfeeding our daughter. She shrunk back to a D when she was done.
Reportedly my wife's mother had an A at most prior to her first pregnancy. I would guess around a D, now, but I'm not sure.
Well, the main complaint my formerly breast feeding friends & sister say is that when the breasts shrink back after weaning they also lose firmness, and it can be a bummer in that it feels like part of your body suddenly aged.
Ouch.
If that french feminist (can't remember her name) ever fulfill her dream of medical technology enabling gestation inside males willing to experience it ... I'm no longer willing. It's my body and I say NO. :-)