Question

What factors could lead to the rise of a new species?

Answer 1

Hint: Any disruption in the genetic equilibrium can result in the formation of a new species.

Complete answer:
The process of formation of one or many completely new species from an existing species is known as speciation.

Several factors can be responsible for speciation or formation of new species, they are as follows:
- Genetic Drift: It can be described as variations that are introduced in a species accidentally and result in the formation of new species. It is a random accidental or chance process which results in variation. Genetic drift is also known as the Sewall Wright effect. It has two forms:
Founder Effect: The process of formation of a new species from a small isolated population of a species that is different genetically from the parent species population.
Bottleneck Effect: It is the formation of a new species, due to the separation or survival of a small group of the population from a large parent population due to natural calamities like earthquakes, floods, etc. This small population then goes on to become a different species.
- Natural Selection and Survival of the fittest: Fitness according to Darwin is reproductive fitness. Natural selection is of three types, stabilizing selection, directional selection, and disruptive selection.
- Genetic Mutations: Mutations can alter the genome of organisms and may lead to the formation of a new variant.
- Isolation: Isolation here refers to reproductive isolation which prevents interbreeding due to different physical and biotic barriers. It is of two types, geographical isolation (interbreeding can not occur as the population is isolated from each other due to geographical barriers) and reproductive isolation (include internal barriers which prevent interbreeding from being successful).
- Genetic Recombination
- Gene flow or gene migration: Flow of alleles between two populations through interbreeding.

Note: It has to be remembered that speciation is a natural process, but now new species of microbes and animals are being produced at a very fast rate by the methods of recombinant DNA technology. These organisms if released into the natural environment might disrupt several natural phenomena and cause ecological imbalances.