Mother Nature has been creating weird and wonderful chemicals for more than three billion years; and we are only beginning to sift through these hidden treasures. New technologies enable us to find, analyze and manipulate molecules as never before. While today's laboratory scientists can synthesize new molecules from scratch at a pace unimaginable just a few decades back, promising compounds produced by nature's most creative creatures increasingly provide the optimum starting points.
Indiscriminate logging and killing of wild life in our little known forests especially the mangrove forest of the Sunderbans, Rangamati, Sylhet etc. signal a catastrophic extinction of these vast untapped wealth and resources. Given the voracious appetite for land and wild life such as the Royal Bengal Tiger and spotted deers in the Sunderbans, elephants in the forest of Chittagong and precious wood, these forests of mystical beauty will one day remain in the history books only. As the forest area shrinks, the majestic Royal Bengal Tigers disappear from our sight. The plight of tigers only symbolises the tragic fate of the whole country's wild life to-day. To be sure, some 40 years ago, forests draped the country like an elegant green gown covering at least one fourth of the land area -- nourishing and protecting wildlife. To-day this very gown is in tatters, slashed by human interests, covering only about seven per cent of the country.
Human beings are the only ones who possess the power to snuff life out of all other species in the world. But that power can very often turn malevolent and that is where we have to be cautious. Unfortunately for us Bangladeshis, we've been more than malevolent -- we've been natural born killers of wild life and plunderers of forest resources. We've failed to understand that the earth is one intricate ecosystem of links by which all life is shaped. Lose one specie and a thousand others will be on the brink, eventually threatening our survival. Not only in our own region, far in the African plain elephants, giraffes and lions and elsewhere some rare species like the Javan rhinoceros, Philippine eagle lechwe, the Kudu and lilac breasted roller seem to be disappearing fast. Scientists are worried that in a few generations' time they could be lost even to the children of Africa and Asia.
One thing is very certain. As we enter the 21st century, a new global economy draws nations ever closer. But our growing interdependence hinges on much more than technology and trade. For we are linked intrinsically by the physical and biological webs that sustain life on planet -- and increasingly, by the threat of their unraveling. Indeed, unless we reach across borders and face this threat in an united effort, the next century may dawn on an Earth in ecological crisis, with half of the species gone and our children and grand children enduring deadly floods, drought and disease brought on by global warming more frequently. Protecting the environment to-day is a sacred human obligation, as important to us as safe neighbourhoods and good schools. What is needed now for the government as well as individual is to look beyond our own cities and countryside, and provide the leadership needed to put all nations on a cleaner, and more sustainable path to prosperity.
But there are obstacles on the way. Desperate shortages of human and financial capital impoverish both the people and their land in Africa and Asia. Bangladesh situation is much more critical. The country has now a population figure of 130 million with a per capita income of 270 U.S dollars. Most obviously with limited factors of production and negligible technological progress, the population growth is unsustainable. Policies to improve the state of the environment as such has to be linked with population control mechanisms.
Although book analysis says total forest land in Bangladesh is about 2.6 million hectares or 18 percent of the country's surface land, shockingly the actual forestry now stands about 7 percent of the land area. But unquestionably, forestry contributes to both economic and ecological stability of the country. The preservation as well as conservation of wild life and other forest resources was being depleted at an alarming rate due to poaching, deforestation, and loss of habitat. Mostly located in the Chittagong Hill Tracts, Sylhet, Tangail and Mymensingh, large sections of the forests are felled illegally every day, where forest officials in league with other timber mill owners have caused this destruction of national wealth with no money going to state coffers. Apart from the financial loss the resulting loss of bioderversity either here in Bangladesh or elsewhere in the world carries a price for us all. For instance, the rosy periwinkle, a plant native to Madagascar,has proved potent against childhood leukemia. Yet other rare species on this island nation, most found nowhere else on Earth are disappearing faster than scientists can catalogue. But this biodiversity and its wonderful efficacy seem stranger than fiction. At the dawn of the 21st century, with technology evolving at an ever increasing rate, many people mistakenly believe the natural world has nothing left to offer us in the way of new medicines. This could not be further from the truth. Mother Nature has been creating weird and wonderful chemicals for more than three billion years; and we are only beginning to sift through these hidden treasures. New technologies enable us to find, analyze and manipulate molecules as never before. While today's laboratory scientists can synthesize new molecules from scratch at a pace unimaginable just a few decades back, promising compounds produced by nature's most creative creatures increasingly provide the optimum starting points.
Time and again, we find that plants and animals make strange molecules that chemists would never devise in their wildest dreams. For example, researchers could not have invented the anti-cancer compound "taxol" taken from the Pacific Yew tree. "It is too fiendishly complex a chemical structure", says natural-products chemist Gordon Cragg, of the U.S. National Cancer Institute. Some of the most promising natural wonder drugs come from compounds not usually associated with healing: poisons. Merck is marketing a blood thinner based on venom of the deadly saw-scaled viper. A protein from another Asian pit viper is being studied because it appears to inhibit the spread of melanoma cells related to skin cancer and a compound called SNX-482 from the venom of the Cameroon red tarantula may lead to new treatments for neurological disorders.
Natural pharmaceuticals offered by biodiversity are still underutilized. Only a few hundred wild species have served to stock our antibiotics, anti-cancer agents, pain killers and blood thinners. For example, "fox gloves" (Shial Kata) mostly found in our region has been found to be so useful to millions of people with heart ailments. These flowers provide the digoxin which regulate the heartbeat. Many sufferers from hypertension and high blood pressure owe a debt to the "Indian snake root shrub" (Sharpamool) for its reserpine. And the search continues. Extracts from an Amazonian oak tree coagulate proteins, immensely helping scientists in their search for an AIDS vaccine. People sleep deeply and breathe easily during operations, thanks to scopolamine derived from mandrake and thorn apples. Women who take the contraceptive pill for granted would not be taking it at all were it not for the yam (Sweet potato). The large tuber is the source of the pill's active ingredient, diosgenin. Even the healthiest among us take compounds first discovered in fragrant meadow sweet and willow bark and now known as aspirin. Only about 13 plants so far known have healed and soothed millions of people. They're but the merest sample over a quarter of all prescribed medicines based on plants.
Yet, of the estimated 3,50,000 flowering plants believed to be in existence, tens of thousands remain undiscovered and only some 5,000 have been tested exhaustively for their pharmaceutical attributes. Now this vast store of known and potential medicines is under threat. Every species everywhere has the potential to teach us something new. How tragic then it is that just as innovative technologies give us the ability to take advantage of natural compounds as never before, we continue to threaten the world's species and the habitats on which they depend. The European leech source of a new blood thinner was almost wiped out by overzealous collectors. The same is true for poison dart frogs, producers of may intriguing chemicals. Tropical cone snails and sponges, known to harbour analgesic and anticancer compound respectively, live on coral reefs, one of the planet's most endangered maritime ecosystems. Known as Silphion to the Greeks and Silphium to the Romans as the most effective female contraceptive to the ancient Greeks and Romans, the plant is now extinct. Experiment on lab rats with common fennel (a close relative of Silphium's) these days did indeed show contraceptive activity. Unfortunately researchers in the sophisticated laboratories in the U.
S. were unable to test the efficacy of silphium itself. Because of the insatiable demand for it in the ancient world silphium went extinct about 1500 years ago.
Assuringly, the biochemistry of the vast majority -- millions -- of other species is an unfathomed reservoir of new and potentially more effective substances. The reason is to be found in the principles of evolutionary biology. Caught in an endless arms race, these species have devised myriad ways to combat microbes and cancercausing runaway cells. We have scarcely begun to consult them for the experience stored in their genes. True, it is difficult enough to assess an ecosystem but in these days of dire economic situation followed by climatic disruption, policy makers need to understand how various ecosystems interact. Deforestation in mountains can worsen floods in grasslands or agricultural lands below as was in the case of China and more recently in Madagascar. The same thing is being done in parts of Chittagong and Sylhet in our region. So humans have hurt coastal/marine ecosystems directly by draining wetland, cutting mangrove, trawling oceans for fish and destroying reefs and lagoons. But illegal logging of woods in the lush hill forest of Lathitilla, Sylhet, once home to wild elephants and other mammals and rampant killing of Royal Bengal Tigers and deers in the Sunderbans are indications that these little known forest areas will disappear fast in our country. On the other hand, by doing so we also damage the ecosystem indirectly as rivers transport to the coasts the effluents and byproducts of agriculture, industry, urban areas, logging and dams. It is tempting to put in the words of Bill Clinton, immediate past President of the U.S. when he visited China in 2000 and met environmentalists in the scenic city of Guilin. Clinton was fascinated at the growing awareness at the grassroots level. Clinton said, "Ultimately our best hope may be that even where governments lag, their people understand both the stakes and the urgent need for action". Here in Bangladesh we must also take hold and succeed. In the struggle against history's profound environmental challenges, we must participate for the sake of our children, our country and this planet.
Md. Asadullah Khan is Controller of Examinations, BUET
Source: The Daily Star, Dhaka, February 1, 2002