BIOL 115 Lecture Notes - Lecture 10: Nuclear Transfer, Dairy Cattle, Genetic Variation
Document Summary
Describe the concept of punctuated equilibrium in evolution and how it differs from the gradual process proposed by darwin. Darwin"s gradualism: darwin proposed that populations changed slowly and gradually over time. Yet fossil records show periods where the environment doesn"t change, the population also remains stable. Only when there is a change in the environment does natural selection apply. Punctuated equilibrium: the fossil records suggest that organisms evolve suddenly, and remain stable for millions of years. The theory of punctuated equilibrium proposes that, instead of gradual change, there have been periods of rapid evolution followed by long periods of stability or equilibrium. Analyse information from a secondary source to outline the evidence that led to beadle and tatum"s one gene-one protein" hypothesis and explain why this was altered to one gene-one polypeptide" hypothesis. Beadle and tatum studied bread mould mutations brought about by x-rays, known as mutants.
