Question

Explain importance of fossils as proof of evolution.

Answer 1

1. Carbon consumption of animals and plants stops after death and only the decaying processes of C-14 take place continuously.
2. The ratio of C-14 to C-12 changes constantly with time as C-12 is non-radioactive in dead plants and animals.
3. The time passed since the death of a plant or animal can be calculated by carbon dating i.e. by measuring the radioactivity of C-14 and the ratio of C-14 to C-12 present in the remains of the dead organism.
4. The oldest fossils are buried deep in the Earth’s crust, while the younger ones occupy the upper surfaces. Hence, fossils of invertebrates are found buried deep as they are very old and belong to the Palaeozoic era. The fossils of Pisces, Amphibians, and Reptiles were obtained in consecutive layers. The Mesozoic era was dominated by reptiles, while the Cenozoic era showed the presence of mammals and birds.
5. Thus, the study of fossils is an important aspect of evolution since it can be used in paleontology and anthropology for determining the age of the fossils and deducing information about their ancestors.