BIO 115 Lecture Notes - Lecture 28: Housefly, Coalescent Theory, Last Universal Common Ancestor
Document Summary
Scientists use genetic tools to understand steps towards domestication. Gradual increase in cob size documented by archaeologists. Domestic dog diversity created in last 15,000 years. Pesticides and herbicides act as agents of selection. Weed reduction insecticide and herbicides are gaining resistance. Creation of refuges can slow the evolution of resistance. Comes at a cost when bt is not present. Bt crops select for resistance in pests. Creation of bt-free refuges favours bt-susceptible insects. How humans can impose selection pressures on the environment. Urbanization can impact the traits under selection in certain species. Creepus species of flower: selection for the dispersal seed mechanism is much lower in city environments. Much more fragmented landscape that this plant thrives in. Evolution of shorter male horns due to hunting. Horn length in this species has declined dramatically from the mid 70"s till now. Reason for this pattern hunters prefer the longer and larger horns. These large males aren"t leaving offspring this is selection.
