Question

why is biodiversity important to the survival of all life on Earth? Describe at least two ways that biodiversity contributes to our survival.

Answer 1

Biodiversity plays an important role for the survival of mankind because of following reasons.

1. Source of food
• Of over 3000 species of food plants only 150 species have been commercialized. It can be seen that 85% of the food output is produced by less than 20 species.
• Two third of food is being produced by only three crops rich in carbohydrates -wheat, corn (maize) and rice. • Utilisation of more and more food plants has to be made.
2. Source of fats and oils
• The major oil seed plants are soybean, coconut, cotton seed, peanut and sunflower, sesame, safflower, mustard and oil palm.
• Some newer species of oil are being investigated for obtaining high performing lubricants. E.g. Bitter colocynth, jojoba seed.
3. Fibres
The major sources of fibre are cotton, jute, flax, hemp, sun hemp, rosella, coir and agave. Search is continually on for new superior fiber yielding plants.

4. New varieties
• Domesticated commercial species are improved for various traits, especially disease resistance by crossing them with wild relatives.
• Rice has been made resistant to four main diseases by crossing it with wild species ( Oryza nivara) from India. • Potato has been made resistant to late blight ( trait from Solanum demissum), Potato Mosaic Virus Y ( trait from Solanum stoloniferum), Fusarium and five races of cyst nematodes ( trait from Solanum spegazzini)
5. Drugs and medicines
• A number of drugs are based on plant products. • Rosy periwinkle (Charanthus roseus = Vinca rosea) yields alkaloids (Vincristine and vinblastine) which are useful for treatment of leukaemia. The same are now being synthesized chemically.
• Other drugs derived from plants are Morphine (Papaver somniferum for pains), quinine (from bark of Cinchona ledgeriana for malaria), taxol (from bark of Yew; Taxus brevifolia and Taxus baccata for treating cancers), reserpine (from Rauvolfia serpentine for treating blood pressure and schizophrenia) etc.
• 25% of all drugs are currently sourced from 120 species of plants. • Traditional systems of medicine world over use thousands of local/ wild plants for treating various maladies. It is possible to manufacture innumerable synthetic products from plant chemicals. These are called botanochemicals.
6. Aesthetic value
Biodiversity has a lot of value in terms of aesthetics and attraction of people towards a particular place. Aesthetic value of biodiversity can be utilized for ecotourism, bird watching, wildlife, pet keeping and gardening. 7. Cultural benefits