BIOL 101 Lecture Notes - Lecture 16: Population Bottleneck, Allele Frequency, Thomas Robert Malthus
Document Summary
Does evolution occur: unambiguous answer: yes, we can watch it happen in the lab whenever we want , see examples in nature. Variance in reproductive success: when females invest more, sexes look different, when males invest parental care look the same. Observing evolution in the lab: fruit flies die after 20 hours without food. Selecting for flies that live longer over generations shift survival from 20 160 hours. Antibiotic resistance: spontaneous mutation (~1 of billion, plasmid gene transfer. Common descent with modification: a single common ancestor lies at the base of evolutionary tree. Darwin and his big idea: before darwin, most people believed: Earth 6,000 yrs. old: two important patterns: Fossils resembled not identical living organisms in same area. Thomas malthus: economist, essay on the principle of population (1798-1926, populations potentially grow faster than food supplies. Darwin : variations: best win" worst lose", struggle for existence favorable variations preserved.