This latest in a series of reports from NPR is out.
Over the past year, NPR and ProPublica have been investigating why American mothers die in childbirth at a far higher rate than in all other developed countries.
A mother giving birth in the U.S. is about three times as likely to die as a mother in Britain and Canada.
In the course of our reporting, another disturbing statistic emerged: For every American woman who dies from childbirth, 70 nearly die. That adds up to more than 50,000 women who suffer “severe maternal morbidity” from childbirth each year, according to the Centers for Disease Control and Prevention. A patient safety group, the Alliance for Innovation on Maternal Health, came up with an even higher figure. After conducting an in-depth study of devastating complications in hospitals in four states, it put the nationwide number at around 80,000.
I’m not going into great detail about this, but I do want to make a few related salient points. Continue reading NPR: For Every Woman Who Dies In Childbirth In The U.S., 70 More Come Close
A new species of peccary has been discovered in the Amazon. It’s different from other peccaries in that it appears to be a frugivore. It also lives in pairs or very small family groups. This is, of course, exactly what one might expect. Frugovores eat high quality food, while the other peccaries eat lower quality food. Higher quality food is rare and dispersed so it is difficult to get into larger groups. Continue reading New Pig Species Discovered
As you probably know, everyone should drink milk. Lots and lots and lots of milk. All your life. Or so says the American Dairy Industry, often using those sexy posters of famous people with milk smeared on their faces.
The truly amazing thing about those posters is that the people in them more often than not seem to have an ethnic identity that I, as a trained Biological Anthropologist (and thus keeper of this sort of knowledge) can easily see contraindicates milk consumption. Most of these individuals would likely be unable to break down the lactose in the milk because they have the “wild type” or “normal” allele that facilitates the shutdown of lactase production some time in early life.
Now let’s be clear about this. We humans are mammals, and as mammals, we drink mother’s milk while young. This is facilitated by the production of lactase, an enzyme that breaks down the main energy bearing molecule in milk, the sugar lactose. But your basic well adapted mammals should not bother producing the enzyme lactase after weaning normally occurs … maybe a few years after in a long-lived mammal like humans … because it is inefficient and potentially risky to produce enzymes you don’t need.
Why is it inefficient? Well, there are thousands and thousands of enzymes and if we just produced all of them all the time in all our cells, that would be really costly of raw materials and energy, both of which are required to produce them. So, evolution has shaped, via the brilliant designer of Natural Selection, our multicellular bodies to produce enzymes only in the cells they are needed in (from which they may be exuded on occasion, as is the case with lactase, a digestive enzyme). This is much more efficient. By extension, the system should be (and usually is) selected to produce specific enzymes when they are needed instead of all the time from birth to death. By doing this we save a lot of raw materials and energy.
Continue reading Got milk (alleles)?
|Chimp, Australopith and
Human Teeth Compared.
The evolution of human diet followed a major zig (as in zig-zag) in a wholly unexpected direction, followed by the most significant biological innovation to ever occur among multi celled animals: The invention of cooking. I’m actually going to point you to two papers on this topic, and provide a brief summary of the ideas here.
Let’s start with the bold assumption that humans evolved from a chimpanzee-like animal. This is tantamount to saying that the last common ancestor of chimpanzees and humans was, essentially, pretty much like a chimpanzee. At another time, I’ll write a post on why this is a good assumption, but for now lets just go with it. Some large percentage of human evolution experts like this assumption, a bunch of others hate it (which is the usual pattern for most ideas in human evolution).
A mammal’s diet is reflected in physiological attributes that can be discerned from the fossil record. Body size, the nature of the teeth and associated muscles, possibly the shape of the mouth’s cavity, and even the overall size and shape of the gut may be closely connected with diet.
If we draw a direct line from a presumed chimpanzee-like ancestor to modern humans, Continue reading The Evolution of Human Diet