Medical Miracles Slipping Away as Extinction Claims Species

The core of the book explores seven threatened groups of organisms valuable to medicine, including amphibians, bears, cone snails, sharks, nonhuman primates, gymnosperm trees such as pines and spruces, and horseshoe crabs. It illustrates what is lost to human health when species go extinct.

But the authors stress that the book's conclusions should not be used as a license to harvest wildlife in a way that puts further pressure on already threatened, vulnerable and endangered species. Instead they should be a spur for greater conservation and improved management of species and the ecosystems they inhabit.

The book, "Sustaining Life," is published by Oxford University Press, and has been supported by the UN Environment Programme, UNEP; the Secretariat of the Convention on Biological Diversity; the UN Development Programme; and the International Union for the Conservation of Nature, IUCN.

The findings, announced today during the Business for the Environment Summit in Singapore, come in advance of the next meeting of the parties to the Convention on Biological Diversity set for Bonn, Germany in May. There, delegates from nearly 190 countries as well as business, scientific and NGO leaders will seek to accelerate actions that will cut the rate of loss of biodiversity by 2010.

Introducing the book, UNEP chief Achim Steiner said, "Habitat loss, destruction and degradation of ecosystems, pollution, over-exploitation and climate change are among the powerful and persistent impacts that are running down the planet's nature-based capital, including the medical treasure trove of the world's biodiversity."

But the experts warn that many of the life forms of economic and medical interest may disappear before we can learn their secrets, or before we even know they exist.

Co-author Jeffrey McNeely, chief scientist at the IUCN, says, "While extinction is alarming in its own right, this book demonstrates that many species can help save human lives. If we needed more justification for action to conserve species, this book offers dozens of dramatic examples of both why and how citizens can act in ways that will conserve, rather than destroy, the species that enrich our lives."

Rheobatrachus silus, the southern gastric brooding frog, is now extinct. (Photo courtesy Wikimedia)

A promising treatment for peptic ulcers has already been lost due to extinction of the southern gastric brooding frog, Rheobatrachus, which was discovered in undisturbed rainforests of Australia in the 1980s.

The frogs raise their young in the female's stomach where in other animals they would be digested by enzymes and acid.

Preliminary studies indicated that the baby frogs produced a substance, or perhaps a variety of substances, that inhibited acid and enzyme secretions and prevented the mother from emptying her stomach into her intestines while the young were developing.

The authors point out that the research on gastric brooding frogs could have led to new insights into preventing and treating human peptic ulcers which affect some 25 million people in the United States alone.

"But these studies could not be continued because both species of Rheobactrachus became extinct, and the valuable medical secrets they held are now gone forever," say authors Eric Chivian and Aaron Bernstein based at the Center for Health and the Global Environment, Harvard Medical School.

Nearly one-third of the approximately 6,000 known amphibian species are threatened with extinction.

Nine bear species are threatened with extinction including the polar bear; the giant panda, and the Asiatic black bear.

Many bears are at risk because they are killed for body parts, such as gall bladders, which can command high prices in black markets in China, Japan and Thailand.

Asiatic black bear (Photo courtesy IUCN)

Several medical benefits have been discovered from the study of bears, including the development of ursodeoxycholic acid, found in the gall bladders of some bear species such as polar and black bears.

The substance is used to prevent the build up of bile during pregnancy; dissolve certain kinds of gallstones; and prolong the life of patients with a specific kind of liver disease, known as primary biliary cirrhosis, giving them more time to find a liver transplant.

Cone snail species may produce as many as 70,000 to 140,000 peptide compounds, large numbers of which may have value as human medicines, yet only a few hundred have been characterized.

One compound, known as ziconotide, is thought to be 1000 times more potent than morphine and has been shown in clinical trials to provide significant pain relief for advanced cancer and AIDS patients. Another cone snail compound has been shown in animal models to protect brain cells from death during times of inadequate blood flow.

It could prove a breakthrough therapy for people suffering head injuries and strokes and may even contribute to therapy for patients with Parkinson's and Alzheimer's.

But almost 70 percent of the approximately 380 cone snail species surveyed have more than half their geographic range within areas where coral reefs, their main habitats, are threatened.

German Environment Minister Sigmar Gabriel said, "We are currently in the process of wiping nature's hard drive - at a tremendous pace and without any hope of restoring the data once it is lost. We have to comprehend the extent of the damage we are doing to ourselves so that we can bring about a change of course."

"In order to curb the ongoing destruction of biodiversity before 2010 and thus reverse the trend, we must finally adopt effective measures at international level. This is our overriding goal for the upcoming 9th Meeting of the Conference of the Parties to the Convention on Biological Diversity in Bonn."

Ahmed Djoghlaf, executive secretary of the Convention on Biological Diversity, said, "The Earth's biodiversity, much of which has yet to be discovered, provides a unique opportunity to improve not only the health of current but also that of future generations."

"However as species are lost so too are our options for future discovery and advancement," Djoghlaf said. "Thus 'Sustaining Life' provides poignant evidence that biodiversity loss is not merely an environmental issue but one which affects us on a very basic, fundamental and personal level."

Copyright Environment News Service (ENS) 2008. All rights reserved.