Recently, Y.-H. Percival Zhang and colleagues demonstrated a method of converting cellulose into starch and glucose. Zhang thinks that it can be scaled up into an effective industrial process, one that could produce a thousand calories of starch for less than a dollar from cellulosic waste. This would be a good thing. It’s not just that are 7 billion people – the problem is that we have hardly any food reserves (about 74 days at last report). The usual assumption is that any drought or blight would be local, but that isn’t necessarily so. We might have another Tambora-style eruption, or an asteroid big enough to generate tidal waves and kick up a lot of dust – or wheat rust might get out of control.
If this works, we might have a reserve in hand. At least until the population runs up to the new Malthusian limit.
Apis mellifera, the common honeybee, seems to have originated in Africa and spread from there to Europe and Asia. Moving into temperate climates required major behavioral change that led to honey hoarding and ability to form a winter cluster.
European honeybees are half-tame, probably because beekeepers selected for lower levels of aggressiveness. People collect honey from African honey bees, but have never domesticated them, so the optimal strategy for African honey bees is to go down fighting. Which they do: they’ll chase you for a mile once they get their dander up.
This has probably been going on for a long, long, time. It may well go back before anatomically modern humans. I say that because of the greater honeyguide, which guides people to beehives in Africa. After we take the honey, the honeyguide eats the grubs and wax. A guiding bird attracts your attention with wavering, chattering ‘tya’ notes compounded with peeps and pipes. It flies towards an occupied hive and then stops and calls again. It has only been seen to guide humans.
I would not be surprised to find that this symbiotic relationship is far older than the the domestication of dogs. But it is not domestication: we certainly don’t control their reproduction. I wouldn’t count on it, but if you could determine the genetic basis of this signaling behavior, you might be able to get an idea of how old it is.
Honeyguides may be mankind’s oldest buds, but they’re nasty little creatures: brood parasites, like cuckoos.
Stalin died 60 years ago, and he’s still dead. That’s something to celebrate.
Carl Zimmer’s blog reports a new paper by some Harvard geneticists proposing that differences in incidence of diabetes of pregnancy between native New Yorkers and immigrant Bangladeshi women reflects adaptation to wheat and a high carb diet in Europeans.
The hypothesis seemed dubious to me, so I wrote to several colleagues about it. Since I haven’t gotten permission to quote them, I will simply call them BC (Bangladeshi colleague) and VC (Vanilla colleague). Here is our correspondence:
Zimmer reports today on a new paper from Sabeti et al., much of which is about gestational diabetes. The suggestion is that Anglo women are adapted to a high carb diet and can keep their blood sugar down during pregnancy, Bangladeshi women can’t. Here are two quotes:
The Harvard researchers suggest that the shift to high-carb agriculture in Europe led to more women dying of gestational diabetes. Women with mutations that lowered their blood sugar level during pregnancy were favored by natural selection. And today, European women enjoy the benefits of that suffering: a low risk of gestational diabetes.
A woman in Bangladesh has a very different history behind her. Her ancestors ate fish, unprocessed rice, and other foods with modest levels of carbohydrates.
Does this ring right to you? Rice according to current tables is as or more glycemic that white bread.
no, i don’t think any of these make much sense. fwiw, it looks like bengalis didn’t live in bengal until the past 2,000 years. and didn’t everyone eat unprocessed carbs until recently?
As I understand it rice, like wheat, must be milled to remove the bran to allow storage. You ever eat much unprocessed rice back home?
unprocessed? no. my parents started eating it in the USA for health. when they go back to bangladesh ppl think they are insane.
Don’t know about India, but across a lot of SE Asia and Indonesia, rice-eating in significant quantities is a very recent status thing. This is a big topic among sustainability-types, who are trying to figure out how to get people to go back to growing some local starches plus manioc and yams, but can’t get good market prices because they’re “low-class” food.
Anyone know about the history or ecology of milling grain?
In yet another example of long-delayed discovery, it turns out that you can treat a number of filarial diseases, such as elephantiasis or onchocerciasis (river blindness) with tetracycline or doxycycline.
Heedless of the evolutionary imperative to do no unnecessary harm, these parasitic worms cause all kinds of trouble, some of it by a surprising mechanism. They carry Wolbachia, a symbiotic bacteria, and it seems Wolbachia proteins are responsible for most of the inflammatory damage, through an endotoxin-like activity. By the way, Wolbachia is the Chickenman of parasites and extremely interesting in itself.
Antibiotic treatment sterilizes filiarial nematodes, inhibits larval development, and reduces viability of adult worms. I will bet any amount of money that poorly educated doctors (drunken remittance men, etc) in Africa had good results (by accident) using tetracycline on people with filarial disease as far back as the 1950s. It must have happened again and again and again – and since few of those doctors ever went to Harvard, I’ll bet some of them noticed it. There is a good chance that one or two of them actually tried to write up their results, but of course no journal would publish that kind of nonsense.
I was thinking again about the consequences of having more small-effect deleterious mutations than average. I don’t think that they would push hard in a particular direction in phenotype space – I don’t believe they would make you look weird, but by definition they would be bad for you, reduce fitness. I remembered a passage in a book by Steve Stirling, in which our heroine felt as if her brain ‘was moving like a mechanism of jewels and steel precisely formed.’ It strikes me that a person with an extra dollop of this kind of genetic load wouldn’t feel like that. And of course that heroine did have low genetic load, being the product of millennia of selective breeding, not to mention an extra boost from the Invisible Crown.
So far, although I have occasionally been called an ‘extreme right winger’, an anarchist, or a Commie, I have only once been called a God-damned hippie – due to this article of mine.
A metaphorical cee-gar to the first person who figures out how the editors messed up one line.