NEET BIOLOGY

Detailed explanation-1: -Structures which are reduced and are perhaps even nonfunctional, such as the human tail and the human appendix, are considered vestigial structures. The tail, of course, functions for balance in many mammals, and the human appendix may have served digestive functions in herbivorous ancestors.

Detailed explanation-2: -A vestigial structure is a biological structure that has lost a major ancestral function and is usually drastically reduced in size. Well-known examples include the eyes of blind cave fishes and blind cave salamanders, and the diminutive wings of kiwis and emus.

Detailed explanation-3: -Vestigial organs are organs, tissues or cells in a body which are no more functional the way they were in their ancestral form of the trait. It is authentication of evolution and hence, were helpful in explaining adaptation. Such a structure can arise due to gene mutation which causes a change in the proteins.

Detailed explanation-4: -The examples of human vestigiality are numerous, including the anatomical (such as the human tailbone, wisdom teeth, and inside corner of the eye), the behavioral (goose bumps and palmar grasp reflex), and molecular (pseudogenes). Many human characteristics are also vestigial in other primates and related animals.

Detailed explanation-5: -Often, these vestigial structures were organs that performed some important functions in the organism at one point in the past. However, as the population changed due to natural selection, those structures became less and less necessary until they were rendered pretty much useless.