"Without noncovalent bonds, such vital life activities as metabolic reactions, duplication of DNA, and movement of materials within cells could not occur." Cell and Mole Bio, Karp Knowing how key noncovalent bonds are to every aspect of life how could it begin with covalent bonds instead? Doesn't it make sense that the origin of life was variants of noncovalent bonds? And just a side note. To get variants to select from, you would have to have variant conditions in the environment - correct? The alternative of never changing conditions would NOT produce variants. Thus to get variants you would have to have an environment with variatable conditions - a heat cycle.