Question

Study of history of life forms on earth is called
(a) Evolutionary biology
(b) Morphology
(c) Physiology
(c) Biogenesis

Answer 1

Hint: The study of various life forms by the scientists have proved that mutation or some heritable changes are responsible for the development of various life forms.

Complete step by step answer:
Evolutionary biology deals with the study of the history of various forms of life on the earth. 
Basic evolutionary theory
Charles Darwin had reported that the various life forms are not only similar amongst themselves, but it also shares similarity with life forms that existed many years ago. Some life forms become extinct while some new life forms arise. The variation in various life forms enables a particular living organism to survive better in a particular environment than the other variation. Also, some life forms outbreed others. All these are because of natural selection.
Natural selection: Those life forms that will fit better in a particular environment will have more progeny than other life forms and hence it is selected by nature.
Evolutionary evidence
- The fossil fuel which was sedimented in various rocks proves the existence of various life forms.
- According to morphology and anatomy, evolution has been divided into convergent and divergent evolution.
Convergent evolution: The structure has been evolved to perform the same function ((i.e,) the structure will be different and the function remains the same) is called convergent evolution. The wings of a butterfly and birds look different but they perform the same function. They do not have a common ancestor.
Divergent evolution: The structure remains the same and the function changes according to the environment of that particular life form. Forelimbs of whales, bats, and humans have similarities in the forelimb structure but they differ in the function. They have a common ancestor.
Furthermore, morphology deals with the study of the size, shape as well as the structure of plants and animals. Physiology deals with the study of the mechanism of all living things. It includes the study of cell functions at the molecular level, the behavior of the entire body, and the response of our body to various environmental factors. Biogenesis deals with the origin of one living form from the other living form. For example, a hen lays eggs and a new hen arises from the egg.
So, the correct answer is ‘(a) Evolutionary biology’.

Note: Hugo DeVries stated that a large single-step mutation known as saltation is responsible for the evolution of various life forms. On the contrary, Darwin believed that the mutations are small, gradual, and directional.