Few of our closest relatives, the great apes, cooperate with each other as extensively as meerkats. Human cooperation probably has an ancient history, and by studying meerkats, which depend on their group for survival, we gain a window into the evolution of cooperative societies.
Our research on these issues progressed steadily until, two years into the study, disaster struck. The irregular rainfall of the Kalahari failed completely, and the remaining grasses in the park shriveled and died. Twisters cruised up and down the riverbed, and the springbok and wildebeests left to search for the last remnants of grass in the dunes. At first the meerkats hung on, digging for beetles and scorpions in the loose sand, but gradually their condition deteriorated and they were forced to forage farther and farther from bolt-holes— quick-escape burrows scattered throughout their range—and spend more and more of their time without the protection of sentinels.
Predators quickly took their toll: The Jacksons' dominant female was the first to be killed, followed rapidly by the dominant male and by Juma's older sister—all three probably taken by one of the martial eagles that rode the morning thermals over the riverbed.
Eventually Juma was left alone with three younger sisters. For the next year these four were inseparable, a cautious group whose seamless alternation of sentinel duty ensured that no predators could get close to them. Other groups fared worse: Six of the ten groups that we had habituated were wiped out, leaving vacant ranges.