Earth has entered the sixth mass-extinction event thanks to activities of humans and this extinction event can be seen as a parallel to the one that caused extinction of dinosaurs, scientists have said.

According to International Union for Conservation of Nature (IUCN) as many as 41 percent of all amphibian species and 26 per cent of all mammals are at risk of extinction due to a number of reasons – most of them because of human activities – including habitat loss, overexploitation, invasive organisms, pollution, toxification and climate change.

The new study saw scientists map ranges of 27,600 species of birds, amphibians, mammals and reptiles – a sample representing nearly half of known terrestrial vertebrate species – and analyzed population losses in a sample of 177 well-studied mammal species between 1990 and 2015. Scientists determined that more than 30 percent of vertebrate species are declining in population size and range. Of the 177 mammals for which the researchers had detailed data, all have lost 30 percent or more of their geographic ranges and more than 40 percent have lost more than 80 percent of their ranges.

The study’s maps suggest that as much as 50 percent of the number of animal individuals that once shared Earth have disappeared, as have billions of animal populations. This amounts to “a massive erosion of the greatest biological diversity in the history of Earth,” the authors write.

Decline in population of species and their extinction will effectively rob us of the crucial ecosystem services such as honeybees’ crop pollination, pest control and wetlands’ water purification. We also lose intricate ecological networks involving animals, plants and microorganisms – leading to less resilient ecosystems and pools of genetic information that may prove vital to species’ survival in a rapidly changing global environment.

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