Page 312 - Environment: The Science Behind the Stories

TABLE 11.5 Major Types of Animals at Risk That
The world’s biodiversity holds a still-greater treasure Offer Potential Medical Uses
chest of medicines yet to be discovered. It can truly be said
that every species that goes extinct represents one lost oppor- SPECIES AT RISK POTENTIAL MEDICAL USES
tunity to find a cure for cancer or AIDS. A recent international Amphibians • Antibiotics, alkaloids for
survey highlighted animals that show particular promise yet 30% of all species are painkillers, chemicals for treating
may be lost to extinction before we can profit from what they threatened with extinction. heart disease and high blood
have to offer (Table 11.5). We lost such an opportunity in the pressure
two species of gastric brooding frogs recently discovered in • Natural adhesives for treating
tissue damage
the rainforests of Queensland, Australia (see top photo in • Ability to regenerate organs and
Table 11.5). Females of these bizarre frogs raised their young tissues could suggest how we
inside their stomachs, where in any other animal, stomach might, too.
acids would soon destroy them! Apparently the young frogs • “Antifreeze” compounds that
exuded substances that neutralized their mother’s acid produc- allow frogs to survive freezing
tion. Any such substance could be of immense use for treating might help us preserve organs
human stomach ulcers, which affect 25 million U.S. citizens. for transplants.
Sadly, both frog species went extinct in the 1980s, taking their Sharks • Squalamine from sharks’ livers
medical secrets with them forever. Overfishing has reduced popula- could lead to novel antibiotics,
tions of most species. Some risk appetite-suppressants, drugs
extinction. to shrink tumors, and drugs to
Biodiversity boosts economies through fight vision loss.
tourism and recreation • Study of salt glands is helping
address kidney diseases.
Besides providing for our food and health, biodiversity can
generate income through tourism, particularly for developing
countries in the tropics that boast impressive species diver-
sity. Many people like to travel to experience protected natural
areas, and in so doing they create economic opportunities for Horseshoe crabs • A number of antibiotics are
residents living near those areas. Visitors spend money at local Overfishing is sharply being developed.
businesses, hire local people as guides, and support parks that diminishing populations. • The compound T140 may treat
employ local residents. Ecotourism (p. 88) can thereby bring AIDS, arthritis, and several
cancers.
jobs and income to areas that otherwise might suffer poverty. • Cells from blood can help detect
The parks and wildlife of Kenya and Tanzania are prime cerebral meningitis in people.
examples. Ecotourism brings in fully a quarter of all foreign
money entering Tanzania’s economy each year. Leaders and
citizens in both nations recognize biodiversity’s economic ben-
efits, and as a result they have managed their parks and reserves Bears • An acid from bears’ gallbladders
diligently. Ecotourism is a vital source of income for nations Nine species are at risk of already treats gallstones and
such as Costa Rica, with its rainforests; Australia, with its Great extinction. liver disease, and prevents bile
Barrier Reef; and Belize, with its reefs, caves, and rainforests. buildup during pregnancy.
The United States, too, benefits from ecotourism; its national • While hibernating, bears build
parks draw millions of visitors from around the world. bone mass. If we learn how, we
Ecotourism can serve as a powerful financial incentive could treat osteoporosis and hip
for nations, states, and local communities to preserve natu- fractures, which lead to 740,000
ral areas and reduce impacts on the landscape and on native deaths per year.
species. Yet as ecotourism increases, an overabundance of • Hibernating bears excrete no
visitors to natural areas can degrade the outdoor experience waste for months. Learning how CHAPTER 11 • Bi odiv ER si T y A nd Cons ER vAT i on Bi ology
could help treat renal disease.
and disturb wildlife. Anyone who has been to Yosemite, the
Grand Canyon, or the Great Smoky Mountains on a crowded Cone snails Compounds from these snails
summer weekend can attest to this. As ecotourism continues Most live in coral reefs, which are include one that may prevent
to grow, so will debate over its costs and benefits for local threatened ecosystems. death of brain cells from head
communities and for biodiversity. injuries or strokes, and a
painkiller 1000 times more
People value connections with nature potent than morphine. So far
just a few hundred of the
70,000–140,000 compounds
Not all of biodiversity’s benefits to people can be expressed these snails produce have been
in the hard numbers of economics or the day-to-day practi- studied.
calities of food and medicine. Some scientists and philoso-
phers argue that people find a deeper value in biodiversity. Adapted from Chivian, E., and A. Bernstein, 2008. Sustaining life: How
Harvard University biologist Edward O. Wilson has popu- human health depends on biodiversity. Oxford Univ. Press.
larized the notion of biophilia, asserting that human beings 311

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