Biology 121 Quiz B on evolution 1. Malthus's ideas were incorporated into the theory of evolution propounded by Darwin and Wallace. Assume this is a major river and no mouse ever crosses from one side to the other. If you cannot answer that question, state what other information you need to be able to give an answer. Biology 121 Quiz B on evolution - Key 1.
Variation is the result of sexual reproduction and mutation.
Mutations produce the alternative forms of genes, while sexual reproduction mixes the genes in new combinations. Meiosis and fertilization do the mixing, and in meiosis it is crossing over and independent assortment that mix up the genes in the gametes. A. Malthus said that population growth outstrips resources. B. Darwin and Wallace said that as the populations produce too many offspring for the environment to support, competition and natural selection result. 4. A. natural selection, because under different selective pressures, natural selection will probably move the gene pool faster than will drift and mutation.