Question

Explain the 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 varies over time, as C-12 is non-radioactive in dead plants and animals.
3. The time elapsed 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 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, invertebrate fossils 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 was characterised by mammals and birds.
5. Thus, the study of fossils is an important aspect of evolution, as it can be used in palaeontology and anthropology to determine the age of fossils and deduce information about their ancestors.