BIOL 1070 Lecture Notes - Lecture 2: Dna Replication, Heritability, Allele Frequency
Evolution through natural selection happens in thousands and thousands of years. Population doesn"t evolve if the allele frequencies does not change from one generation to the next. Components of evolution by natural selection: heritability, overproduction. Evolution involves a change in the proportion of variants (alleles) in a population. Evolution can only occur if there is variation in a population. Mutations (errors in dna replication) are the primary source of new variation. Good, bad and neutral mutations happen with equal probability. Beneficial mutations increase in frequency and deleterious mutations decrease in frequency under natural selection. This principle of preservation he called natural selection. Start with two populations of mussels (one group with allele a and other with allele b) With time alleles are passed on multiple generations. Those species are now surviving-idea of natural selection.