Early and modern conceptual history of
Earth’s biodiversity – Central theme in natural science.
‘Adam’ was asked not to eat fruit of a tree.
Gr. Phil. Aristotle. (384-322BC) recognized 500-600 spp.= modern folk classification.
19th century folk biology got redundant.
20th century our knowledge dominated by evolution.
Fig: An illustration from an old herbal, illustrating the Doctrine of Signatures. Note the resemblance between the human teeth and the cone scales of pine and pomegranate seeds.
Thinking Biodiversity: Main themes in texts from the conceptual origin of biodiversity in 1980.
|1||Inventory||Global total species, habitat total, specific total,
knowledge gaps, etc.
|2||Loss rates||Deforestation, settlement, agriculture, over
exploitation, habitat loss, etc.
|3||Value||Food, energy, medicine, chemical raw materials,
ecosystem services, etc.
|4||Economics||Ecosystem functioning valuation, timber production,
economic products, cloths, foods, etc.
|5||Conservation||Gene bank, botanical gardens, ecoparks, rare spp.,
|6||Attitudes||Philosophical, psychological, ethical, moral, religion, etc.|
Environmental campaigning started since mid century.
Formation of conservation bodies, research funding, political lobbying & increasing public awareness.
World bodies taking care: WWF, Greenpeace, individual efforts, e.g., famous TV presenter Peter
Scott, Brigid Bardot as activists for anti-whaling, anti-seal, anti-fur posters, etc.
Media impact– Rain forests deeply photogenic, wild life has ancient history.
TV as strong media to fulfill appetites e.g., BBC Wildlife, Geo, Discovery, ANZ animal planet, Planet Earth, The Blue Planet, Canal D, CNN, Da Vinci
Learning, Encuentro etc.
Wildlife media developed After World War II.
BBC natural history unit founded in 1957.
Global Threats-Late 1980’s public supports were excellent.
Green Peace-Activists made familiar with wildlife, threats to it & planetary health, oil spill, ozone.
- Tropical forests treasure for medicine & food.
- Lulo (Solanum quitoense) yields juice in Colombia and Peru.
- Amaranthus sp., healthy food in USA.
- Crop improvement by using wild genes.
- Maize discovery, Mexico, from wild Teosinte (wild grass), 1970’s.
- Peru, 1972, genes from weedy tomato increased tastes of conventional tomato, benefited US tomato industries by making million of $ profit.
- Wild crop strains useful to make disease resistant crops.
Biodiversity through time: importance of time
At present threats to Biodiversity taken very seriously because we know many plants & animals got extinct.
We hear & see tales of dinosaurs, mammoths, living fossils, etc. of past plants & animals we share today in planet not same spp. as in past.
Biodiversity not static, has evolved over huge time period known as ‘deep time’ , 100’s & 1000’s & millions of years.
In those periods- ecosystems, habitats, all were different, only present life intimately linked with them via evolutionary processes, so every one has an ancestor.
Present spp. may be different but many of their life-styles now a days significantly similar to those extinct creatures.
Many dead, many changed but as a whole today’s diversity, a continuation of past biodiversity.
Extinction of biodiversity over ‘deep time’ can provide good lesson to us for future conservation.
Past history can solve many questions e.g., extinction rate whether qualitatively different, if current losses qualitatively different, if more spp. lost at faster or slower rate, over larger or smaller area.
History may help us to know:
- Causes of extinction.
- Vulnerability of spp.
- Useful tactics, strategies of conservation by studying ancient spp., survived despite of all threats.
Biodiversity’s future based on knowing past.
This Article is completely based on by the lecture of Dr. Azmal Hossain Bhuiyan, Professor, Department of Botany, University of Dhaka.
Some info and pictures have been added by author.