List these by filling in the blanks 1-3 below. For 1-3 below, explain how each of these processes can cause evolution. Use an example such as changes in a group of red and green lizards to clarify your explanations. Natural Selection Explain how evolution by natural selection works by working through the numeric example for red and green lizards that was given in lecture. Thus both types of lizard could produce 2 offspring in a normal life span in the absence of predation.
Hawks are the main predator.
They kill more of the conspicuous than the inconspicuous lizards. Assume that the lizards with the conspicuous color live an average of only 1 year, so produce an average of one offspring in their lives, whereas lizards with the inconspicuous color live an average of 2 years, so produce an average of 2 offspring in their lives. Show what will happen to the population over time, in terms of the ratio of red to green lizards, if the environment stays the same for at least 4 generations. Show what will happen to the ratio of red to green lizards after this if a drought occurs that kills most of the green vegetation, leaving the lizards exposed on red dirt and red rock. Show what will happen if the drought continues for at least 3 generations.