Guns, Germs & Steel

languages and for more than half (nearly 200 million) of the Niger-Congo speakers. But all those 500 Bantu languages are so similar to each other that they have been facetiously described as 500 dialects of a single language.
Collectively, the Bantu languages constitute only a single, low-order subfamily of the Niger-Congo language family. Most of the 176 other subfamilies are crammed into West Africa, a small fraction of the entire Niger-Congo range. In particular, the most distinctive Bantu languages, and the non-Bantu Niger-Congo languages most closely related to Bantu lan-

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guages, are packed into a tiny area of Cameroon and adjacent eastern Nigeria.
Evidently, the Niger-Congo language family arose in West Africa; the Bantu branch of it arose at the east end of that range, in Cameroon and Nigeria; and the Bantu then spread out of that homeland over most of subequatorial Africa. That spread must have begun long ago enough that the ancestral Bantu language had time to split into 500 daughter languages, but nevertheless recently enough that all those daughter languages are still very similar to each other. Since all other Niger-Congo speakers, as well as the Bantu, are blacks, we couldn't have inferred who migrated in which direction just from the evidence of physical anthropology.
To make this type of linguistic reasoning clear, let me give you a familiar example: the geographic origins of the English language. Today, by far the largest number of people whose first language is English live in North America, with others scattered over the globe in Britain, Australia, and other countries. Each of those countries has its own dialects of English. If we knew nothing else about language distributions and history, we might have guessed that the English language arose in North America and was carried overseas to Britain and Australia by colonists.
But all those English dialects form only one low-order subgroup of the Germanic language family. All the other subgroups—the various Scandinavian, German, and Dutch languages—are crammed into northwestern Europe. In particular, Frisian, the other Germanic language most closely related to English, is confined to a tiny coastal area of Holland and western Germany. Hence a linguist would immediately deduce correctly that the English language arose in coastal northwestern Europe and spread around the world from there. In fact, we know from recorded history that English really was carried from there to England by invading Anglo-Saxons in the fifth and sixth centuries a.d.
Essentially the same line of reasoning tells us that the nearly 200 million Bantu people, now flung over much of the map of Africa, arose from Cameroon and Nigeria. Along with the North African origins of Semites and the origins of Madagascar's Asians, that's another conclusion that we couldn't have reached without linguistic evidence.
We had already deduced, from Khoisan language distributions and the lack of distinct Pygmy languages, that Pygmies and Khoisan peoples had formerly ranged more widely, until they were engulfed by blacks. (I'm using 'engulfing' as a neutral all-embracing word, regardless of whether

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the process involved conquest, expulsion, interbreeding, killing, or epidemics.) We've now seen, from Niger-Congo language distributions, that the blacks who did the engulfing were the Bantu. The physical and linguistic evidence considered so far has let us infer these prehistoric engulfings, but it still hasn't solved their mysteries for us. Only the further evidence that I'll now present can help us answer two more questions: What advantages enabled the Bantu to displace the Pygmies and Khoisan? When did the Bantu reach the former Pygmy and Khoisan homelands?
To approach the question about the Bantu's advantages, let's examine the remaining type of evidence from the living present—the evidence derived from domesticated plants and animals. As we saw in previous chapters, that evidence is important because food production led to high population densities, germs, technology, political organization, and other ingredients of power. Peoples who, by accident of their geographic location, inherited or developed food production thereby became able to engulf geographically less endowed people.
When Europeans reached sub-Saharan Africa in the 1400s, Africans were growing five sets of crops (Figure 19.3), each of them laden with significance for African history. The first set was grown only in North Africa, extending to the highlands of Ethiopia. North Africa enjoys a Mediterranean climate, characterized by rainfall concentrated in the winter months. (Southern California also experiences a Mediterranean climate, explaining why my basement and that of millions of other southern Cali-fornians often gets flooded in the winter but infallibly dries out in the summer.) The Fertile Crescent, where agriculture arose, enjoys that same Mediterranean pattern of winter rains.
Hence North Africa's original crops all prove to be ones adapted to germinating and growing with winter rains, and known from archaeological evidence to have been first domesticated in the Fertile Crescent beginning around 10,000 years ago. Those Fertile Crescent crops spread into climatically similar adjacent areas of North Africa and laid the foundations for the rise of ancient Egyptian civilization. They include such familiar crops as wheat, barley, peasj beans, and grapes. These are familiar to us precisely because they also spread into climatically similar adjacent areas of Europe, thence to America and Australia, and became some of the staple crops of temperate-zone agriculture around the world.

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Origins of African crops, with examples

(sorghum, pearl millet) S

Figure 19.3. The areas of origin of crops grown traditionally in Africa(that is, before the arrival of crops carried by colonizing Europeans),with examples of two crops from each area.
As one travels south in Africa across the Saharan desert and reencoun-ters rain in the Sahel zone just south of the desert, one notices that Sahel rains fall in the summer rather than in the winter. Even if Fertile Crescent crops adapted to winter rain could somehow have crossed the Sahara, they would have been difficult to grow in the summer-rain Sahel zone. Instead, we find two sets of African crops whose wild ancestors occur just south of the Sahara, and which are adapted to summer rains and less seasonal vari-

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