Question

Fossils are the **, traces or impression of the ** animals and plants of geological past. Fossils are formed layer by layer in the earth' crust. Fossils of prokaryotes were found in older rocks than those of eukaryotes. Invertebrates were formed before vertebrates. Among vertebrates, fishes appeared earlier than amphibians and amphibians appeared earlier than reptiles, which are earlier than birds and mammals. Thus, fossils provide evidence for evolution.

(i) What is the main factor on which formation of fossil depends ?

(ii) What is fossil dating ? Why the study of fossils important ?

Answer 1

(i) Decomposition of organisms.

(ii) The age of fossils can be estimated by fossil dating.

The study of fossils is important because :

(i) It helps to analyze the ** history of plants and animals.

(ii) It helps to measure the geological time.