- Define 6th Mass Extinction.
- Discuss the problem of extinction of species.
- Mention the causes.
The Holocene extinction, popularly called the 6th Mass extinction, is an ongoing extinction event of species and biodiversity during the present Anthropocene epoch due to human activities.
Problems of Extinction : evolution & extinction are intertwined. The Global Report on Biodiversity and Ecosystem Services (2019) by IPBES shows that the current rate & scale of extinction is unprecedented, being caused majorly by humans. It says, 1 million animal & plant species face extinction and will be extinct within decades. About 40% of amphibian species are threatened with extinction. Since 1900, number of native species in most habitats have declined by 20%. Another study suggests, the Earth has already lost between 7.5 – 13% of its 2 million known species – a staggering 150,000 – 260,000 species. The WWF’s Living Planet Report 2020 says that Asia Pacific region lost 45% of its vertebrate species in 4.5 decades, while the global average loss is 68%. The loss of vertebrates is highest in Caribbean & Latin America (94%), followed by Africa (65%).
For India, the loss can be higher than the global average with 12% wild animals, 19% amphibians, and 3% birds lost over the past 5 decades. Of about 0.1 million animal species recorded in the country, about 6800 are vertebrates, of which more than 550 species fall in critically endangered, endangered and vulnerable categories, according to ZSI.
Causes: the Living Planet Report 2020 points to 5 major reasons behind biodiversity loss across planet – (a) changes in land & sea use ; (b) overexploitation of species; (c) invasive species & diseases ; (d) pollution and (e) climate change.
Asia-Pacific, including India, is experiencing species loss at a rate higher than the global average with habitat degradation being the biggest trigger, followed by species overexploitation, invasive species & diseases. The role of pollution & climate change is higher at 16%.
Thus, large-scale species extinction is a grave threat to the planet’s biodiversity. Interdependence of intertwining species is what holds the existing system together. Each has a definite ecosystem service (ecological niche) of its own. If one fails, the entire rhythm falls disrupted. So, it is pertinent that expedient restrictive measures must be taken to curb destructive anthropogenic activities & preserve species diversity, if we are to pass a healthier planet to our coming generations.