Define:(i) Vestigial organs (ii) Variations (iii) Neo-Darwinism

1.	Define:(i) Vestigial organs (ii) Variations (iii) Neo-Darwinism
Answer» (i) Vestigial organs are the organs which are non-functional in the possessor but were functional in their ancestors and in related animals. It is evidence of organic evolution. e.g. in human eye, nictitating membrane, vermiform appendix. (ii) Variation is a process by which closely related organisms come to differ amongst them-selves. Genetic drift, mutation, recombination, gene flow, migration, selection are some sources of variation. (iii) According to Neo-Darwinism adaptations are caused due to many forces, natural selection being one of them and that characters are not inherited as such but there are character determiners which control their development.

Answer»

(i) Vestigial organs are the organs which are non-functional in the possessor but were functional in their ancestors and in related animals. It is evidence of organic evolution. e.g. in human eye, nictitating membrane, vermiform appendix.

(ii) Variation is a process by which closely related organisms come to differ amongst them-selves. Genetic drift, mutation, recombination, gene flow, migration, selection are some sources of variation.

(iii) According to Neo-Darwinism adaptations are caused due to many forces, natural selection being one of them and that characters are not inherited as such but there are character determiners which control their development.

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