Question

What is the main cause of extinction of wildlife?
A. Urbanisation
B. Poaching
C. Falling of trees
D. All of the above

Answer 1

Extinction is the termination, usually a species, of a kind of organism or of a set of kinds (taxon). In general, the moment of extinction is known to be the death of the last person of the species, but before this stage, the potential to reproduce and recover may have been lost.

Complete Answer:
- The possible range of a species can be very wide, it is difficult to assess this moment, and typically done retrospectively. This challenge leads to phenomena such as Lazarus taxa, where after a time of apparent absence a species presumed extinct suddenly "reappears" (usually in the fossil record).
- More than 99 percent of all the animals that have ever lived on Earth are believed to have died out, amounting to over five billion animals. It is estimated that there are currently about 8.7 million eukaryote species worldwide, and maybe several times more if microorganisms, such as bacteria, are included.
- Relatively rare events are mass extinctions; individual extinctions, however, are very common. Extinctions have been reported only recently and scientists have become alarmed at the current high rate of extinctions. The degradation of natural ecosystems by human activities, such as cutting down forests and turning land into agricultural fields, is the key cause of extinctions.

So the answer is “Option D”.

Note: Most animals are never scientifically known whether they become extinct. Some scientists predict that by 2100, up to half of the current species of plants and animals could be extinct. A 2018 study suggested that it will take 5 to 7 million years to restore the phylogenetic diversity of 300 mammalian species erased during the human period since the Late Pleistocene.