Abstract:  The development of evolutionary theory, from the original Darwinism through Neo-Lamarckism, Mendelism, Neo-Darwinism to the modern synthetic theory, is herein reviewed. The synthetic theory is again challenged by the new information from molecular investigations and new significant fossil discoveries. As a result, the neutral mutation-random hypothesis and the Threeepisode Cambrian Explosion hypothesis have been proposed.

Key words: Darwinism, Neo-Lamarckism, Mendelism, synthetic theory, molecular biology, fossil investigation, challenge