Write an account on the loss of biodiversity in the world.

(N/A) The biological wealth of the Earth is declining rapidly,and human activities are the major reasons for it. For example,the colonization of tropical Pacific Islands by humans has led to the extinction of more than $2,000$ native bird species.
The International Union for Conservation of Nature and Natural Resources $[IUCN]$ was founded in $1948$ and is headquartered in Switzerland. It works in the field of nature conservation and the sustainable use of natural resources.
The $IUCN$ Red List of Threatened Species is an inventory of the global conservation status of biological species,compiled in the Red Data Book,which was initiated in $1964$.
Some examples of recent extinctions include:
$(i)$ Dodo (Mauritius),Quagga (Africa),Thylacine (Australia),Steller's Sea Cow (Russia),and three subspecies of tiger (Bali,Javan,and Caspian).
$(ii)$ About $27$ species have disappeared in the last $20$ years globally. More than $15,500$ species are currently endangered. Presently,$12\%$ of all bird species,$23\%$ of all mammal species,$32\%$ of all amphibian species,and $31\%$ of all gymnosperms face an extinction threat,with amphibians appearing most vulnerable.
$(iii)$ The $2012$ Red List contains $132$ plant and animal species from India. Some endangered species include the Asiatic lion,Bengal tiger,Lion-tailed macaque,Nilgiri langur,and Ganges river dolphin.
Fossil records reveal that large-scale loss of species occurred even before humans appeared. There have been five episodes of mass extinction over the last $3$ billion years due to natural calamities (e.g.,extinction of dinosaurs). Currently,the Earth is heading towards the sixth extinction,which differs from previous episodes in its rate. Current extinction rates are estimated to be $100$ to $1,000$ times faster than pre-human times,driven by human activities. If this continues,$50\%$ of species might be wiped out within the next $100$ years.
Effects of loss of biodiversity include:
$(i)$ Decline in plant production.
$(ii)$ Lower resistance to environmental perturbations such as drought.
$(iii)$ Increased variability in ecosystem processes such as plant productivity,water use,and pest and disease cycles.