Free The Kingdom of Rarities by Eric Dinerstein Page A

with their cacophonous squawks. For these canopy residents—monkeys, macaws, and thousands of others—this is the sweet life on the breezy, green roof of the rain forest. The chance to join them in this restorative stratum, even for an hour, is a relief from the claustrophobia of the dark, dank forest floor. For the elevated naturalist, the exhilarating climb to the top serves as a refresher course—a moment to ponder when our ancestors, too, were arboreal.
    The tropical rain forest is full of common species such as ants, nematodes, and fungi that contribute heavily to the unseen machinery of an intact rain forest, yet it is a bountiful Kingdom of Rarities as well: Many living things in this landscape, from the tops of emerging giant trees to the thin soils covering their roots, exhibit several forms of scarcity. Some insect species exist only in the canopy of a single tree species, but there they mass in numbers. The giant trees orchestrate life in the Amazon and create a three-dimensional stage for millions of smaller organisms and staggering diversity, too: a single tree may hold more ant species than are found in the entire British Isles. Yet the distribution of these trees is quite different from that in England and western Europe, where a few elms, maples, beeches, or oaks may dominate a large patch of forest. In the Amazon, particular trees, such as mahogany and members of the Brazil nut family, may range eastward across Brazil but be spread out as individuals, occurring maybe only once every few hectares, sometimes even more dispersed. The jaguars andpumas that wander below their crowns and several of the monkeys that live in them also range widely but are thinly distributed. The macaws that fly across the canopy also appear across much of the lowlands but are locally scarce.
    The unusual flash of brightly colored birds in an all-green realm triggered a raft of intriguing questions that had been lingering in my mind for years: Why might such species be rare? And why are rare creatures as different as macaws, monkeys, cats, and rain forest trees so similar in the character of their spacing patterns? Was one single factor the cause, transcending whether an organism was covered in fur, feathers, or leaves? And why do biologists believe that some of the scarcest species exert a tremendous influence on the workings of the rain forest?
    Up in the Manu viewing tower, the distant sound of communal throat clearing caught Sue’s attention: the hubbub was a troop of capuchin monkeys expressing their displeasure at an intruder lurking nearby. Perhaps a jaguar had walked past and settled along the riverbank or a forest eagle or falcon had passed overhead. “As long as the capuchins stay hidden in the branches, they’re generally safe from aerial predators,” Sue related. “But they’re scared to death of an opportunistic spotted margay cat that could climb up after them.” At all costs, capuchins and other monkeys avoid the ground, where they would be an easy mark for a jaguar. This largest of South American cats is known by its local name,
yaguara
, which means “to kill with one pounce.”
    Consistently locating jaguars was central to George’s research project. He sought to answer one of the most pressing questions of tropical biology: How much is enough? He wanted to know how much habitat area was needed to conserve jaguars, pumas, peccaries, tapirs, and other locally rare Amazon species. Up to now, scientists could only guess or shrug in response.
    Sue had spent the previous five years searching these forests for wild primates, the little-known saki in particular, so she knew all about the wariness of monkeys. The bald-faced saki, part of an unusual-lookinggroup of primates, the pithecians, is distinguished by its long, coarse fur, a pelage seemingly out of place in the tropical rain forest but quite useful as camouflage, an important feature for canopy residents that weigh