Question

Adaptive radiation is
A) Evolution of different species from a common ancestor
B) Adaptation due to geographical isolation
C) Migration of members of a species to different geographical areas
D) Power of adaptation of an individual to a variety of environments

Answer 1

Hint: Adaptive radiation takes place when a new habitat is formed. It was first observed by Darwin.

Complete Answer:
- To solve this question, we must know about Adaptive radiation.
- Adaptive radiation refers to the adaptation of an organism which helps it to spread or radiate into other environments. It is characterised by a large amount of divergence in phenotypes and lineage diversification. It starts with a single ancestor. It results in the phenotypic adaptation of species showing different morphological and physiological traits.
- As the population begins to flourish, intra-specific competition becomes a factor. The resources decrease to sustain a population. Only those species can survive which has adapted to the niche. This adaptation is by the process of natural selection which allows species to survive in the longer term.
- For example, evolution of Homo sapiens from its ancestors. The modern bipedal human evolved for better adaptation to do tasks, the melanin of the skin-it is adapted according to the climatic condition we live in. These adaptations in the long run have changed the genome.

Thus the correct answer is (A) Evolution of different species from a common ancestor is called adaptive radiation.

Note: Ancestral species change into new forms due to environmental factors. This results in change of morphology as well as physiology in the species.