Collapse_ How Societies Choose to Fail or Succeed - Jared Diamond [137]
Instead, the staple food-producing animals in Greenland became hardy breeds of sheep and goats much better adapted to cold climates than were the cattle. They had the additional advantage that, unlike cows, they can dig down under snow to find grass for themselves in the winter. In Greenland today, sheep can be kept outdoors for nine months per year (three times as long as cows) and have to be brought into shelter and fed for only the three months of heaviest snow cover. Numbers of sheep plus goats started off barely equal to cow numbers at early Greenland sites, and then rose with time to as many as eight sheep or goats for every cow. As between sheep and goats, Icelanders kept six or more of the former for every one of the latter, and that was also the ratio at the best Greenland farms during early years of settlement, but relative numbers shifted with time until goat numbers rivaled those of sheep. That’s because goats but not sheep can digest the tough twigs, shrubs, and dwarf trees prevalent in poor Greenland pastures. Thus, while the Norse arrived in Greenland with a preference for cows over sheep over goats, the suitability of those animals under Greenland conditions was in the opposite sequence. Most farms (especially those in the more northerly and hence more marginal Western Settlement) had to content themselves eventually with more of the despised goats and few of the honored cows; only the most productive Eastern Settlement farms succeeded in indulging their cow preference and goat scorn.
The ruins of the barns in which the Greenland Norse kept their cows for nine months per year are still visible. They consisted of long narrow buildings with stone and turf walls several yards thick to keep the barn warm inside during the winter, because cows could not stand cold as could the Greenland breeds of sheep and goats. Each cow was kept in its own rectangular stall, marked off from adjacent stalls by stone dividing slabs that are still standing in many of the ruined barns. From the size of the stalls, from the height of the doors through which cows were led in and out of the barn, and of course from excavated skeletons of the cows themselves, one can calculate that Greenland cows were the smallest known in the modern world, not more than four feet high at the shoulder. During the winter they remained all the time in their stalls, where the dung that they dropped accumulated as a rising tide around them until the spring, when the sea of dung was shoveled outside. During the winter the cows were fed on harvested hay, but if its quantities weren’t sufficient, it had to be supplemented with seaweed brought inland. The cows evidently didn’t like the seaweed, so that farm laborers had to live in the barn with the cows and their rising sea of dung during the winter, and perhaps to force-feed the cows, which gradually became smaller and weaker. Around May, when the snow started to melt and new grass came up, the cows could at last be brought out of doors to start grazing themselves, but by then they were so weak that they could no longer walk and had to be carried outside. In extreme winters, when hay and seaweed stores ran out before the new growth of summer grass, farmers collected the first willow and birch twigs of the spring as a starvation diet to feed their animals.
Greenland cows, sheep, and goats were used mainly for milking rather than for meat. After the animals gave birth in May or June, they yielded milk just during the few summer months. The Norse then turned the milk into cheese, butter, and the yogurt-like product called skyr, which they stored in huge barrels kept cold by being placed either in mountain streams or in turf houses, and they ate those dairy products throughout the winter. The goats were also kept for their hair, and the sheep for their wool, which