Q18 of 43 Page 1

Darwin on his voyage to Galapagos Islands had observed finches having different varieties of beaks. Write the explanation he gave for his observations and the conclusions he arrived at.

On his voyage to the Galapagos Islands, Darwin saw many varieties of finches in the same island. There were the original seed eating finches but some among them had altered beaks and they became insectivorous while others became vegetarian finches. He concluded that different groups of finches had adapted to their geography and hence developed traits that best suited survival in that given geographical area. This process of evolution starting from a point and radiating to other area of geography or habitat is called adaptive radiation.


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OR


Answer the following questions based on the experiment conducted by S.L. Miller in 1953:


(a) Name the gases present in the closed flask.


(b) Why was the flask fitted with electrodes?


(c) Write the observation he made.


(d) State the significance of the observation made by him.