Question

Given below is the diagrammatic representation of a key concept from Darwinism. Identify the correct option.

• A. Natural selection
• B. Branching descent
• C. Saltation
• D. Mutation

Answer 1

The correct option is B Branching descent

Darwin proposed the theory of natural selection. According to him, every organism has a tendency to produce more offspring than actually that can survive. This leads to competition and development of variations in the offspring. Favourable variations (characters that help the organism to face the environment successfully) will be transmitted to the next generation and they will establish whereas the other ones (unfavourable) will die or be eliminated from the environment.

Branching descent and natural selection are the two key concepts of the theory of natural selection. According to him, organisms better suited for the environment with favourable characters will be selected by nature and they will reproduce more offspring. This is called natural selection.


He believed in the origin of new species from a common ancestor due to natural selection. Like branches originating from a trunk of a tree, many species can be evolved from a common ancestor. It is called branching descent. The given diagram represents branching descent from a common species. Example: Darwin's finches (varieties of finches arose from seed eaters) and Australian marsupials (evolved from common marsupials).


Mutation theory was proposed by Hugo de Vries. According to him, new species originated as a result of large discontinuous variations called saltation or mutation that appear suddenly. He believed that mutations lead to evolution but Darwin believed that evolution is a gradual process that occurs due to the accumulation of small variations that are favoured by nature.