The Next Species: The Future of Evolution in the Aftermath of Man (18 page)

Kennedy kept pushing the city on Catskill land purchases, taking film crews into one faulty hospital treatment plant, showing how sewage and wastewater were leaking out into the New York system.
The
New York Post
reported that the Croton reservoir had been shut down due to pollution by sewage, but a New York City spokesman countered that it had been shut down by “organic material.” The late-night television host David Letterman joked that the story “scared the organic material out of me.”

New York City reacted by putting severe restraints on development, new sewage plants, paved surfaces, and farming activities in the watershed, but local residents countered with lawsuits alleging they were being asked to shoulder the cost of New York’s drinking water. The battle ended in a compromise in which the city promised to spend $1.5 billion to buy up land and to construct and repair necessary storm drains and sewage systems. The EPA put off the New York City requirement to build a drinking water filtration system for another five years.

Today the city does everything to guarantee the safety of its water, including following urban sales of Pepto-Bismol and Imodium, both dysentery medicines, to help monitor water quality. Inspectors look for outbreaks of disease caused by single-celled parasites such as
Giardia lamblia
and
Cryptosporidium parvum
in the city’s water supply.
Giardia
can cause cramps and diarrhea, but just one cyst of
Cryptosporidium
can lead to severe illness or death in people with weakened immune systems.

Right now nature is producing the correct amounts of plants, forests, cattails, earthworms, and soil bacteria to keep these and other illnesses out of New York. But if we keep destroying species, the biological equilibrium of these natural systems won’t be there to offer its first line of defense.

How do we destroy species in a watershed? Lots of ways. Invasive pests such as the emerald ash borer, the gypsy moth, and the Asian long-horned beetle threaten Catskill trees. Pollution runoff can overwhelm wetland abilities to trap sediment and heavy metals, and if forests and wetlands go, so do the filtration efforts of the plant roots. Climate change is reducing snowfall in the Northeast, and this exposes the roots of trees to colder temperatures than they would
experience under a blanket of snow, and this can lead to diminished watershed trees. And diminished trees mean diminished microbial communities beneath them.

Protecting natural environments for the sake of their ecosystem services isn’t just a trendy New York City idea. Boston escaped an order from the EPA to filter its water by enacting a watershed program similar to New York City’s that included land purchases, wildlife control, and the regulation of development along tributaries. In Costa Rica, the government charges customers a few cents more on their monthly water bills to pay upstream farmers to preserve and restore the tropical forest. The European Union requires watershed protection of woodlands to ensure the quality and clarity of its water.

In the late 1980s, Perrier water in northeastern France began protecting the Rhine-Meuse watershed for fear that pesticides and fertilizers would compromise the quality of its famous bottled water. In 1990, the water was temporarily pulled off the shelf when it was found to contain the carcinogen benzene, a component of gasoline. Rather than relocate, Perrier spent $9 million to buy six hundred acres around its famous spring. They also entered into long-term agreements with local farmers to use more environmentally friendly practices on four thousand more acres of surrounding land.

Though there is a substantial amount of knowledge about the importance of natural systems to the human economy, the idea hasn’t entered the consciousness of public and political minds. Ecosystem services are the processes by which natural ecosystems and the species they contain sustain human life. They bring us seafood, forage, timber, biomass fuels, natural fiber, pharmaceuticals, and more.

Critical services could include the purification of water and air, mitigation of floods and droughts, breakdown of wastes, generation of soil, pollination of crops, control of agricultural pests, dispersal of seeds, protection from the sun, moderation of temperature,
winds, and waves, as well as enough aesthetic beauty to lift the human spirit.

That’s a lot of important functions. There are legions of ecosystem soldiers contained in some of those goods. One square meter (1.2 square yards) of Denmark pasture, for instance, is populated with approximately 50,000 earthworms, 50,000 insects and mites, and nearly 12 million roundworms. A single gram of soil has about 30,000 protozoans, 50,000 algae, 400,000 fungi, and billions of individual bacteria. These life-forms perform complex natural cycles that are critical to human life.

Without birds and other insect predators, pesticides alone could not control agricultural pests. Without pollinators, plants would not produce food. But many of our ecosystem “soldiers” are in trouble. Nearly twenty thousand species of animals and plants are presently considered at high risk of extinction. A study in
Nature
concluded that if all the species that were considered threatened were lost in this century, and if the rate of extinction continued, we would be on track to lose three-quarters or more of all species within the next century. The International Union for Conservation of Nature has evaluated more than
fifty-two thousand animal and plant species for their ability to survive. Their conclusion is that 25 percent of mammal species are threatened, as well as 13 percent of bird species, 41 percent of amphibian species, 28 percent of reptile species, and 28 percent of known fish species.

Yet we are dependent upon these species for our own survival. Ecosystems of multiple species interact with one another and their environments, and those interactions are essential for human life. They represent the genetic diversity of life, providing the raw ingredients for new medicines, new crops, and new livestock.

Forests store more carbon from carbon dioxide if they have a greater variety of tree species. Streams clean up more pollution if they have a greater variety of microbes. Increasing the diversity of fish means there are greater fishery yields. Increasing plant diversity means they can better fend off invasive plants. Natural enemies better
control agricultural pests if they are composed of a variety of predators, parasites, and pathogens. And ecosystems with a greater biodiversity can better withstand stress such as higher temperatures.

On the other hand, less diversity means less carbon capture, more polluted streams, fewer fish, more invasive plants, more agricultural pests, and more of the species that do poorly under stress.

There is a cultural aspect to ecosystem services as well. Madhav Gadgil of the Indian Institute of Science, Bangalore, and Kamaljit Bawa of the University of Massachusetts Boston divide the consumers of the world into two categories: there are ecosystem people who include forest dwellers, herders, fishers, and peasants who rely on local ecosystems to fulfill most of their needs; and there are biosphere people who extract ecosystem products over a larger international range for commercial purposes. Their rewards are uneven. Even when ecosystem people extract local products for biosphere people, they often do so for low wages because they don’t own the land or the trucks, trains, and airplanes to get the products to commercial markets.

Communities relying on local goods have an incentive to conserve the products so they are there tomorrow. But what happens, says Gadgil and Bawa, is that local people without a controlling interest in the ecosystems nearby aren’t as involved or committed to the long-term survival of these ecosystems. Approximately fifty million people in India live in proximity to forested areas and derive the majority of their living from forest products. But they often don’t have ownership of the lands or the goods.

According to Gadgil and Bawa, if restoration of the environment is to be paramount in economic decisions, then some of that locally controlled, locally extracted, and locally used philosophy has to rub off on the biosphere people. Just because one enjoys blueberries in the middle of winter doesn’t mean that it’s a good or healthy idea to buy produce that comes from the other side of the globe. Next time
you see food that is shipped more than a hundred miles to your door, think about all the pollutants that are coming out of the back of that truck or the fuselage of that plane to get to where you are in winter. It may be benefiting some corporation, the biosphere people, but it’s not beneficial for local economies or local health. And with climate change, local health and local economy are vitally connected with international health and economies.

Training our tongue to enjoy foods that are local and in season is healthier for us all. Says Julia Kornegay, a horticulturalist at North Carolina State University, “Trying to have strawberries and raspberries 365 days a year and expecting them to taste good isn’t sensible.”

Consider also the ecosystem services we derive from diverse tropical plants through the development of medicines. Fifty percent of all medicines owe their origins to species of either plants or animals. Those include tranquilizers, diuretics, analgesics, antibiotics, and more. Aspirin owes its origination to the willow tree. The contraceptive pill originally comes from the wild yam, which grows in the Mexican forests. The bark of the yew tree in the US Pacific Northwest contains the biological compound for Taxol (paclitaxel), which attacks cancer cells that don’t respond to other drugs. Madagascar’s rosy periwinkle has fostered two different drugs that have altered the outcome of a child with newly diagnosed leukemia from one chance in ten of remission in the 1960s (before these medicines) to nineteen chances in twenty today (after their discovery).

Anticancer drugs derived from plants save about thirty thousand lives each year, with an economic savings of $370 billion in terms of lives saved, suffering reduced, and work hours maintained. Many recent anticancer drugs have been found in the tropics, but unfortunately this is also where the majority of plant species extinctions have occurred.

Norman Myers at Oxford points out that Eli Lilly, a global pharmaceutical company, exploiter of the rosy periwinkle for
two anticancer drugs, has profited with over $100 million a year in sales going
back to the 1960s. Madagascar, where the plant was taken, hasn’t received any of that. This gives that country little incentive to protect the remaining tropical forests even though they may contain the seeds of discovery for a host of other important pharmaceuticals.
Homo sapiens
evolved from an ancestor who hunted for a living, going to each new area, killing the animals, and using the plants. Though our technology has rapidly expanded, our primary instincts are back in the Stone Age.

The forest itself is part of our treasure chest of natural resources, one that has many ecosystem services to offer, but again one that we fail to appreciate. If there are trees by the road or in our neighborhood, then all is well. But if deforestation occurs off the road, in other states, or other countries, we object less forcefully. Out of sight, out of trees.

A prime example of man’s selective values can be found in the forests of Central America. I met Dalia Amor Conde, an assistant professor at the Max-Planck Odense Center, in Odense, Denmark, at Flores, a city in the northern department (province) of Petén, Guatemala. The city is located on an island in Lake Petén Itzá, just outside Tikal National Park, famous for its Mayan ruins and its wildlife. Conde was born in Mexico and got her PhD at Duke University, where she began
studying jaguar movements in the tropical forest of Central America to determine their habitat and how roads and other infrastructure planned for the region might affect them.

Her goal is to save enough contiguous land to allow jaguars to migrate between isolated populations, keeping the gene pool of the animal mixed and vital. In the process, this encourages the preservation and vitality of a host of plants and animals that reside in the same ecosystem. It is known as the umbrella effect. By saving this charismatic species, Conde hopes to also save the multitude of animals, plants, and birds that reside under the jaguar’s umbrella.

On a misty tropical morning, she took me to a local zoo in the middle of Lake Petén Itzá. The zoo had a spotted jaguar whose head
and muscular body looked quite regal. We both squatted down to get an eye-level look at the animal, though the jaguar ignored our presence while it paced around its enclosure. This cat is the third-largest feline in the world after the tiger and the lion, and the largest in the western hemisphere. Conde had been on a number of expeditions in the tropical forest whose purpose was to capture jaguars and then release them into the wild with radio collars so biologists could track their movements.

She described to me one hunt in the rain forest surrounding the Mayan ruins of Calakmul in the Yucatán, where birds filled the air with their calls and howler monkeys roared from the treetops. She’d accompanied a caravan of vehicles filled with four biologists, two trackers, five dogs, and a veterinarian to check bait stations along a dirt road through Calakmul National Park. The bait consisted of large chunks of sterilized goat meat spiked with enough drugs to slow the animals down. They were placed every mile at seven spots along a dirt road.

The tracker was Tony Rivera, a former jaguar hunter and now director of EcoSafaris. He got out of his car and announced that the big cat had taken the bait, and the frenzy of dogs in the back of the truck told him the animal was near. Though the group had been up since 3 a.m., everyone suddenly came alive, piled out of the cars, and readied for the hunt.

Rivera let the dogs go, and they took off into the jungle—the biologists doing their best to keep up. As the sound of the dogs’ barking changed, Rivera quickened his pace, approaching a tree in which the jaguar had taken refuge. The dogs were pulled back. Rivera raised his rifle, took aim, and fired a tranquilizer dart into the animal’s side. Soon the drug took effect, and the biologists were assessing the cat’s health and attaching a radio collar to its neck to follow the animal’s movements.