Answer the following question.
Explain with suitable examples the importance of anatomical evidence in evolution.
Anatomical evidences help us to study how species have evolved over a period of time. Analogous structures support the theory of evolution and explain the fact that how species build up adaptations in order to fit in an environment whereas homologous structures help us to understand common ancestry. For example, if we compare the hands of humans with cat’s foreleg, flipper of whale and patagium of bat, we see that each of these organism use these structures are differently. But still there is a similarity between the structure of bones and joints which indicates that somewhere or the other these animals may have originated from common ancestors. This is an example of homology. Another example which explains analogous features is the arctic fox and the ptarmigan bird, Both of them change colours from dark brown to white during seasonal changes. They do not show common ancestry in way but since, they are found in the same habitat they are adapted to colour change.
Anatomical evidence is important as a physical proof for evolution. The anatomical evidence are majorly of two kinds:
Analogous structures: These are structures that have similar functions and appearance but have different biological make-up. This is a proof for evolution that unrelated species, when forced to live in similar conditions, adapted to this- but differently. examples- Body shape, size, and colour in sharks and dolphins
Homologous structures: these are structures with similar biological make-up but different functions. This supports evolution that related species when exposed to different environments, adapted accordingly. examples: Wings of birds and bats.