NEET BIOLOGY

Detailed explanation-1: -Homologous structures provide evidence for common ancestry, while analogous structures show that similar selective pressures can produce similar adaptations (beneficial features). Similarities and differences among biological molecules (e.g., in the DNA sequence of genes) can be used to determine species’ relatedness.

Detailed explanation-2: -Molecular similarities provide evidence for the shared ancestry of life. DNA sequence comparisons can show how different species are related. Biogeography, the study of the geographical distribution of organisms, provides information about how and when species may have evolved.

Detailed explanation-3: -To establish the age of a rock or a fossil, researchers use some type of clock to determine the date it was formed. Geologists commonly use radiometric dating methods, based on the natural radioactive decay of certain elements such as potassium and carbon, as reliable clocks to date ancient events.

Detailed explanation-4: -Using embryology, scientists can identify common ancestors through structures present only during development and not in the adult form. Biogeography offers further clues about evolutionary relationships. The presence of related organisms across continents indicates when these organisms may have evolved.