Earth is the only spaceship with life on it. Animals, Plants and microorganisms maintain a delicate balance with a variety of life forms we call Biodiversity. Individual species and ecosystems have evolved over millions of years into a complex ofinterdependence. It is like a jigsaw puzzle of inter-locking of spieces. Among the all life form, it is only we; the Homo sapiens, have the ability to change our immediate surroundings and adjust with it quickly due to its ability to use tools. This is one of the reasons, the man, on the top of the evolutionary ladder; consider himself to be on top of all species rather than one amongst many species. Each species, which has evolved on this earth has to play a specific role in an ecosystem and also depends on other species for its existence. We know that life has continued to evolve on this earth over millions of years adapting to changing environment. And only those species have survived that have adapted to the changing environment. This change could be due to natural causes like earthquakes, eruption of volcanoes, cyclones, and so on. It even could be due to climate change. The major mass extinction of species in the past was the results of some natural causes. These natural causes of extinctions proved blessings in disguise as same opened up the gates for the evolution of new species like the extinction of Dinosaurs gave way to the evolution on higher forms of mammalians.
But, today environment is changing very fast and species are finding very difficult for itself to adjust with this change. As aresult, the rate of extinction has become very fast. Since the age of modern industrialization, the demand of energy has increased many folds, which we have been obtaining by burning natural resources like firewood, coal and petroleum. There is no denial to the fact that human activities like burning of fossil fuels, deforestation and consequent pumping of gases like carbon dioxide into atmosphere have been responsible for the earth getting hotter and hotter. This has causes a great reduction in the amount of carbon dioxide taken in by plants for photosynthesis and secondly, burning releases huge quantities of carbon dioxide into the atmosphere. This fact is important because carbon dioxide is one of the main greenhouse gase implicated in the current global warming. Average global temperatures have been showing a steadily increasing trend. Snow and ice cover have decreased, deep ocean temperatures have increased and global sea levels have risen by 100 – 200 mm over the last century. If current trends continue, scientists predict that the earth could be on average 1oC warmer by 2025 and 3oC warmer by 2100. These changes, while small, could have drastic effects on the earth’s dynamic system as a whole.
Today, there are threats to our planet arising not only from climate change but the degrading environment, declining availability of fresh water, rivers running dry before they can reach sea, loss of fertile land due to degradation, depleting energy sources and exponentially growing population are the other factors which are posing serious threats to the fragile ecosystem of earth. The pressure on the natural resources is so large as the amount of resources needed to sustain it exceeds what is available. In short, we are, consuming much more than what the earth can sustain. All this has posed a serious challenge to the very existence of life on the earth. If the current rate of exploitation of the natural resources of the earth continues, then it will be dangerous for 12,000 species of wild life and vegetation on earth. If the temperature rises by 1.5-2.7 degree Celsius by the end of the century, then nearly 20-30% of the flora and fauna will become extinct.
In a conference on bio-diversity held in Bann city (2008), International Union for Conservation of Nature (IUCN) has estimated that approximately three species are being extinct every hour due to increasing pollution. Due to the destruction of their natural habit, one out of every four mammalian species is facing the problem of extinction. It includes Chimpanzee and Elephant. One out of every eight species of bird; every third amphibian and 70% of the plants are facing the extinction. According to an estimate, there would be no surviving frog species by 2038.