How did farming start?

No answers: we just don’t know. But Bruce Smith, whose book on The Emergence of Agriculture remains one of the best, recently told an audience at Harvard University that although most people see domestication as “a before-and-after kind of event, with hunter-gatherers before and farmers afterward. The reality … was likely far more complex.”

Hard to argue with that, especially in light of increasing evidence that people were both altering the environment to favour wild food sources and cultivating plants without domesticating them. Smith talked a bit about which plants were domesticated — “early-succession species that did well in disturbed environments that humans could create for them” — but not, at least according to the reports, about whether there’s any scope for additional domestications. We’ve asked before: are there any species that people should be cultivating, and possibly domesticating, now that they have so far ignored? My own contenders would be perennial grains. The plants are there; they just need a few thousands year’s work.

Smith’s lecture was part of a series called Food for Thought. ((Harvard brains hard at work.)) We missed one by my old mucker Richard Wrangham, of How Cooking Made Us Human, but tomorrow, 23 February, Samuel Myers will “discuss troubling trends, including climate change and increased threats from pests and pathogens that may constrain the world’s resources, requiring new approaches to sustainable agriculture.” I wonder whether agricultural biodiversity will feature. Someone go, and tell us.

Nibbles: Sequencing, Agricultural origins, Mating systems, Tomato shelf-life, Beer vs Tea, Soy, Carrot, Seed processing, Screw-pine, Yams, Salicornia, Pollinators

Cracking the code of dog diversity

Another contribution from Michael Kubisch.

Ever wondered why your rat terrier looks so different from your neighbor’s mastiff? Well, eons of selective breeding, of course, which have resulted in genetic differences between these two and other dog breeds. Man’s best friend was undoubtedly among the very first animals to be domesticated, although the huge variety of breeds found today is probably a much more recent phenomenon. Which part of the dog genome, or more pertinently which genes, were involved in generating this diversity remains largely a mystery — but one that many geneticists would like to solve.

A first glimpse has now been provided by a group of scientists who compared genomic data from dogs belonging to ten different breeds using what is called single-nucleotide polymorphisms or SNPs for short. SNPS are very helpful because the presence of a particular SNP sometimes is indicative of the presence of a specific allele at a nearby gene. Similarly, if there are SNPs that differ between two dog breeds it is possible that nearby genes may be different as well and that those genes may have played a role in what sets these breeds apart.

The study revealed 150 areas of the dog genome containing more than 1000 candidate genes that appeared highly variable between those breeds that were examined. Not surprisingly perhaps, several of these genes are known to determine things like coat color, size, skeletal morphology and behavior. However, interestingly, several candidates included genes that are known to act as regulators of other genes, suggesting that some evolutionary changes are not the result of variant alleles of genes but changes in how these genes are controlled. More interesting insights are sure to follow.

Bread or beer? Why choose?

The Cartesian Dualists of the press, if not those of the hallowed groves of academe, are at it again. Der Spiegel, ((And don’t miss the photo slide show there for some sparkling web 2.0 goodness.)) late last month, and The Independent, late last week, report on Professor Patrick McGovern’s latest book, Uncorking the Past: The Quest for Wine, Beer and Other Alcoholic Beverages, almost entirely in terms of which came first, beer or bread.

All the familiar old arguments are trotted out. That bread is actually quite hard to make, while a forgotten soaked seed or rotten fruit is easy enough to swallow and packs enough punch for the brain to say, in Der Spiegel’s memorable phrase, “whatever that was, I want more of it!”. But this convenient opposition ignores things like porridge or gruel, both of which probably represent easier ways of consuming cereals than bread. ((Rachel Laudan writes well on this, and much else.)) Most cereals don’t even make very good bread, at least not as it is understood by European journalists.

Professor McGovern, who runs the delightfully named Biomolecular Archaeology Laboratory for Cuisine, Fermented Beverages, and Health at the University of Pennsylavania’s Museum of Archaeology and Anthropology, is actually claiming far more than that beer came first. He seems to be laying nothing less than the development of settled agriculture, and with it civilisation as we know it, at the door of drunks. According to Der Spiegel:

[A]griculture — and with it the entire Neolithic Revolution, which began about 11,000 years ago — are ultimately results of the irrepressible impulse toward drinking and intoxication.

“Available evidence suggests that our ancestors in Asia, Mexico, and Africa cultivated wheat, rice, corn, barley, and millet primarily for the purpose of producing alcoholic beverages,” McGovern explains. While they were at it, he believes, drink-loving early civilizations managed to ensure their basic survival.

He knits together all sorts of fascinating evidential threads, and at least as far as the articles go, makes a convincing enough case. But then, I remain deeply skeptical of single explanations for anything as complex as the evolution of settled agriculture. And I suspect McGovern does too. As he told The Independent:

As for his theory on how alcohol motivated man to adopt agriculture, McGovern said: “I just wanted to put it out there as a worldwide hypothesis. Then over time maybe the different pieces can be put together from across the world.”

I’m trying really trying to avoid this, but I can’t: I’ll drink to that.