Part 1 of Essay
Evolution is the process by which living organisms originated on earth and have changed their forms to adapt to the changing environment. The earliest known fossil organisms are the single-celled forms resembling modern bacteria; they date from about 3.4 billion years ago. Evolution has resulted in successive radiations ....

Part 2 of Essay
.... as inheritable traits. This generalized hypothesis of evolution by acquired characteristics was not tested scientifically during Lamarck's lifetime. A successful explanation of evolutionary processes was proposed by Charles Darwin. His most famous book, On the Origin of Species by Means of Natural Selection (1859), is a landmark in human understanding of nature. Pointing to variability within species, Darwin observed that while offspring inherit a resemblance to their parents, they are not identical to ....