MYTHS OF THE PRISTINE - The New Wild: Why Invasive Species will be Natures Salvation - page 80

large tree growing in the wild is cultivated. But that is what it is: an ancient cultivated crop.” Thanks to
her efforts, thousands of village women are once more harvesting the nuts; making soup, ice cream, and
cookies with them for their families; and selling them in local markets. A campaign is under way to save
the Maya nut forests. 13
Once seen as a mysterious aberration, it now seems as if the Mayans, like the empire builders of
Angkor, were far from alone in the jungle. Deborah and David Clark were for many years the joint dir-
ectors of the La Selva forest research station in Costa Rica. US scientists had been working there for
years to describe its unchanging ecosystems and burgeoning biodiversity, when twenty years ago the
Clarks emerged to declare this idea a myth. Buried in the soils in the heart of forest, they had found
charcoal, corn pollen, and farm tools. The whole area had been used for agriculture for most of the past
two thousand years. The “pristine” forest was little more than a garden gone wild, abandoned when
Europeans first invaded Central America in the wake of Columbus. “There is no such thing as virginity
out there,” Deborah Clark, now at the University of Missouri-St. Louis, told the New York Times . 14
One reason modern scientists have been reluctant to believe that great civilizations lived in the rain
forest is that their studies show rain-forest soils to generally be too poor to sustain large populations.
But that has changed with the discovery in the Amazon of extensive patches of what archaeologists
have dubbed “dark earths,” or terra preta . They appear to be of human origin, the product of mixing the
natural thin and acidic rainforest soils with a mulch of organic waste and partly burned plant material,
rather like charcoal. Both fertilize the soil. The mulch has enriched the soils with microorganisms that
ensure that it regenerates itself even as it is used for cultivation. “It's at least as good as manure,” says
Bruno Glaser of the University of Bayreuth in Germany.
The dark earths are often full of pottery shards and other detritus of civilization dating back as far
as twenty-five hundred years ago. Many forests that grow in these dark earths are full of Brazil nuts,
lianas, palms, and bamboo, as well as fruit and other forest species that are medicinally or economic-
ally valuable. These are thought to have been deliberately planted in times past. All this suggests an
unexpected truth, says Susanna Hecht of the University of California-Los Angeles. “People have been
farming there—farming hard—for thousands of years.” 15
Now that scholars know where to look for dark earths, they are turning up everywhere. British an-
thropologist James Fraser, of the University of Lancaster, began his career finding them in the Amazon
and is now doing the same in West Africa. 16 In just four months, he found patches at 150 sites across
northern Liberia. In Wenwuta, a village in Liberia's Lofa County, he tells me, “You come down a path
and over a stream, and immediately you come to a ring of cocoa and cotton trees. You can see the
dark earth.” The villagers know about the soils, he says, and actively use them. “If you look closely in
the journals of Victorian explorers and agronomists in the nineteenth and twentieth centuries, you find
occasional reports of farmers burying wood and other vegetation, covering it with soil, and leaving it
to smolder before distributing the resulting ash across their fields. But nobody looked for a pattern or
wondered about their significance.”
In 2012, dark earths were located in northern Borneo, on riversides where humans congregated.
“Local people value these soils for cultivation but are unaware of their origins,” said study author
Douglas Sheil of the Norwegian University of Life Sciences. 17 They also turn up outside forests, es-
pecially in wetlands. Paleoecologist Gail Chmura of McGill University told the American Geophysical
Union in 2011 that garbage mounds left by prehistoric humans might have formed the tree islands of the
Florida Everglades. They are known for their exceptional species richness and were presumed natural.
But they are full of bones, discarded food, charcoal, and bits of clay pots. “This goes to show that human
disturbance in the environment doesn't always have negative consequences,” says Chmura. 18