Question

Explain the original idea of tracing evolutionary relationship.

Answer 1

Paleontology is study of past life based on the fossil records. it furnishes most direct and most reliable evidence for evolution

Answer 2

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evolution does not occur because of single change in DNA or mutation.

organs are complex both structurally and functionally and are genetically regulated by many genes working together.

evolution occurs in many stages by slow changes in DNA or mutation.

the stages occurring during evolution can thus be identified by the different structures formed from common ancestor.

the original Idea behind tracing such relationship was to identify the changes occurring in DNA during reproduction.

the idea at present is called molecular phylogeny.

comparing the DNA of different species helps to give a direct account of changes that occurred in DNA during the formation of a specific species.

these changes accumulate and pass on to the following next generation.

they can be used to trace back and identify the time of their initial occurrence.

this approach is based on the idea that organisms distantly related will accumulate greater number of differences in their DNA.