Dr Abe V Rotor
ll living things, past and present, are progeny of evolution and are interconnected in one way or the other. And each one has a place in the phylogeny, the chart of evolution.
Imagine the organisms in countless numbers assigned in distinct groupings scientists call as “kingdoms,” with the ancient ones occupying the bottom, and the complex ones at the top. And each kingdom is divided into sub-groups arranged in the same pattern – from simple to complex members.
1. From the first Green Revolution – the transformation of man from hunter to farmer some 10,000 years ago – man has narrowed down the diversity of crops and animals according to his needs.
2. The loss of ecosystems all over the world as population and settlements continue to expand has not only predisposed species to extinction but caused permanent damage of these natural habitats, that it is virtually impossible to rebuild them back into their original states.
3. Life on earth is threatened by Global Warming which is causing sea level to rise and flood low lying area. On the hand polar ice and ice caps are melting. Global warming stirs climate change which is causing climatic disturbances. There is a increasing rate and intensity of typhoons, hurricanes, tornado, flooding, drought, and the like.
4. Pollution on land, water and air, in increasing levels brought about by industrialization, growing population and affluence of living, has triggered man-induced phenomena that threaten species and life itself.
5. Rapid population increase, industrialization and affluent living all lead to changing chemistry of the land, water and air. We do not only mix natural elements and compounds; we synthesize them into products foreign to nature. Plastics for example do not decompose, gases from car react to form acid rain, toxic metal run through the food chain and food web, and natural waterways are open sewers. These do not only disturb life; they maim, kill, annihilate; they turn productive areas into wastelands.
6. Man intrudes into the wildlife which continues to shrink. Gone is 80 percent of the rainforests of the world. Ninety percent of the coral reefs have been destroyed by over fishing and by reckless means. The grasslands are shrinking to give way to farming. The sea is being farmed. Islands are now owned by private persons and organizations.
7. Genetic engineering has broken down the barriers that separate species by directly combining genes of different organisms, thereby destroying the identity and integrity of species, and therefore change their behavior and interrelationships.
8. Evolution it seems is no longer a natural process, but one dictated by human intelligence that continues to build from the indulgence on the fruits of the “Tree of Knowledge that makes man as powerful as God,” the very thing that vanished his first ancestors from the biblical Garden of Eden.
Where have all the rice varieties gone?
There are more than 50,000 cultivars of rice presently stored in the Gene Bank of the International Rice Research Institute at UP Los Baños, Laguna. According to IRRI scientists this number represents but a fraction of the possibly rices (the plural of rice to denote distinct genetic variations) of the world since agriculture began some 5000 years ago or so.
Similarly at the Centro Internacional de Mejoramiento del Maiz y Trigo (CIMMYT) in Mexico the gene bank for wheat and corn faces the same problem as in rice, and if this is the case, it is logical that many varieties and cultivars of field crops we know today are but the selected few that man, the farmer, has intentionally preserved. In short, what these banks as well as those conserved by other organizations, are but the remnant of the world’s naturally occurring genetic pool on the one hand, and those genetically modified by man.
A cursory examination of rice sold in the market makes a short list of about a dozen misleading varieties as sinandomeng, wigwag, intan, which are pseudonyms to attract customers for the likeness of quality with those they have been named after.
To validate this observation through field survey one is likely to find even a simpler classification as upland and lowland rice, or aromatic, glutinous, red rice and the like. This is the same observation in the former prairies of North America, now the biggest cereal granary of the world extending across the Canadian border covering the provinces of Alberta, Saskatchewan and Manitoba. According to the Food and Agriculture Organization of the United Nations, there are only 10 major wheat varieties planted on the vast plains. For corn, the indigenous varieties are rare to find on the farm. Hybrid corn – a cross of two or more purified varieties – makes up the bulk of corn produced. Hybrids are unstable genetically. In the succeeding generations the lose hold on the genetic vigor of their parents, resulting in drastic decline in yield.
What is the implication of narrowing down the choice of varieties to be planted commercially?
First, it will result in indirect elimination of varieties in the bottom of the list, by displacement by the preferred ones and by neglect on the [art of the farmer in maintaining them.
Second, fewer varieties planted is food security risk. Severe damage to even only one major variety is likely to result in economic disaster.
Third, the narrowing down of genetic diversity disturbs the ecosystem, laying much on man’s care the survival not only of the cultivated crops but other living things in the area as well, thus leading to the further decrease in diversity and population. The loss of diversity in cereal lands applies as well in other areas as evidenced by the following:
• Vegetables sold in the market are limited to those that are salable, leaving out those that are not, and the so-called “wild vegetables” represented by such vegetables as bagbagkong, papait, sabawil, sword bean, and alukong or himbaba-o.
• The kinds of fruits may be counted by the fingers, and like vegetables, only those that are acceptable dominate the fruit stands. Today it is rare to find such indigenous fruits as tampoy, sapote, batocanag, anonang and the native counterparts of guapple and ponderosa.
• Industrial crops are also suffering of the same fate. Take the following:
1. Dipterocarp species of forest trees (narra family) are now endangered. These include apitong , yakal, tanguili, and guijo.
2. Fiber plants such as maguey (Agave family), ramie, kenaf, jute, abaca, have bee vastly neglected since the introduction of synthetics fibers.
3. Today bamboo groves occupy the fringes of wastelands and certain watershed areas. Traditional bamboo areas, like the Dipterocarp forests, are vanishing, so with many of the species and variety of this so-called giant grass.
4. The increasing demand for firewood has decimated many indigenous sources, what with the open exploitation for day-to-day gathering of firewood in marginal communities. These include madre de cacao, ipil-ipil, acacia, and aroma.
5. Even plants of medicinal value are being exploited severely such as quinine for malaria, banaba for kidney trouble, derris for insect control.
6. Seaweeds suffer the same fate as more resorts are put up, aquaculture selective only to those species of major importance are raised, deleterious effects of pollution, notwithstanding.
Agriculture, the Nemesis of Biodiversity Conservation
Whenever a land is cleared for agriculture five consequences are likely to happen. These are
• Direct elimination of plants and animals which interferes and does not constitute or conform with farming practices.
• Breaking up of the food chain and therefore, the disruption of the food web leads to the disorganization of the ecosystem. For example, a swamp converted into riceland will necessarily lose its natural biological and ecological properties. Loss of habitats results in migration or death of affected species.
• Modern agriculture, with the use of chemical pesticides and fertilizers, is destructive to the ecosystem.
Mismanagement leads not only to loss in productivity, as shown in this formula.
Carrying Capacity/Productivity = Biotic Potential divided by Environmental Resistance
The Carrying Capacity of an ecosystem is dependent upon favorable biological factors (biotic potential), which in turn is affected by the presence of factors that negate them (environmental resistance), among which are lack of water, poor soil condition, and destructive activities of man.
Decreasing productivity therefore, means decreasing biodiversity – which point to devolution of life as a biological phenomenon. x x x
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