Answer:
1. fossil record:
Fossils are organisms that get buried in sedimentary rocks. These are formed at different times. The study of fossils existing in the different rock layers indicates the time period when they existed. Thus different life forms have been formed at different times in the history of the earth.
fossil bird Archaeopteryx is considered as a connecting link between reptiles and birds indicating that birds evolved from reptiles.
2 comparative anatomy:
Homologous organs - such organs that have different embryonic origins but play different roles.
The forelimbs of whale, bat, deer, rabbit
Homologous organs - such organs that are the same in structure and embryonic origin but play similar roles.
wings of a bird and wings of the insect. The wings of the birds are modified
3. DNA sequence can be helpful in finding relations among organisms. Biogeography also helps in identifying the geographical distribution of organisms, to know how and when species may have evolved.
