In the densely populated African nations of Rwanda and Burundi, minority Tutsi ranchers traditionally ruled over the majority Hutu farmers. For 30 years after independence in 1962, both nations struggled with periodic ethnic cleansings. In 1994 extremist Rwandan Hutu leaders launched a systematic genocide, killing 800,000 Rwandan Tutsi, four-fifths of their number. Then, “as the number of Tutsi declined, Hutu turned to attacking each other” (319).

More than ethnic strife was involved. After Tutsi were killed and exiled in the 1960s and 70s, the Hutu took over their land, and food production per capita rose. By the mid-1980s farming had filled in all the available acreage, erosion was rife, and an increased population had pushed per-capita food consumption back to 1960s levels. A Malthusian crisis was brewing.

In the Northwest Rwandan region of Kanama, population densities were higher than in Bangladesh, the most crowded nation on Earth. With nowhere to move and set up a home, most women and all men in their early 20s lived with their parents, putting further loads on each tiny farm until the average person lived off one-seventh of an acre. By 1990 40% of Rwandans were consuming calories below famine levels.