Define evolution. How does it occur ? Describe how fossils provide us evidences in support of evolution.
Answers
Answered by
4
The slow change in the body design of an organism over a long period of time is termed as evolution. It helps an organism to survive in its surroundings.
Evidences of Evolution
Fossils − They represent plants and animals that lived millions of years ago and are now extinct. Different aged rock sediments contain fossils of different life-forms, which probably died during the formation of the particular sediment.
Comparative anatomy and morphology − It shows evidences of the similarities and differences between living forms of today and that of the prehistoric times. Some of the examples of comparative anatomy and morphology are:
Homologous organs − All mammals share the same pattern of forelimbs. Though they perform different functions, they are anatomically similar. This is called divergent evolution and the structures are called homologous structures (common ancestors).
Analogous organs − The pair of organs is not anatomically similar, but performs the same function (e.g., the wings of butterflies and birds). This is called convergent evolution .
Evidences of Evolution
Fossils − They represent plants and animals that lived millions of years ago and are now extinct. Different aged rock sediments contain fossils of different life-forms, which probably died during the formation of the particular sediment.
Comparative anatomy and morphology − It shows evidences of the similarities and differences between living forms of today and that of the prehistoric times. Some of the examples of comparative anatomy and morphology are:
Homologous organs − All mammals share the same pattern of forelimbs. Though they perform different functions, they are anatomically similar. This is called divergent evolution and the structures are called homologous structures (common ancestors).
Analogous organs − The pair of organs is not anatomically similar, but performs the same function (e.g., the wings of butterflies and birds). This is called convergent evolution .
Answered by
1
☆ Evolution is the process of change from simple life forms to complex life forms by gradual change. It is generating diversity and shaping the diversity.
☆ It occurs over the course of time and generations by variation, speciation, natural selection, genetic drift etc. Fossils are preserved traces of living organisms.
☆ It helps us to find the intermediate forms in between two classes etc. For example fossils of archaeopteryx helps us to know better about the intermediate form between reptiles and aves.
☆ It tells about the extinct species through the fossil or their retained body impressions.
☆ It helps us to know the evolutionary relationships.
☆ This also shows the line of development from primitive to complex organisms.
Similar questions