3 Version: Redo 12. There is a population of beetles that typically have black wings. A scientist studying these beetles knows that their eggs hatch in early spring, the young insects grow through the late spring and summer, they lay eggs in the early fall, and they die in the early winter. Recently some beetles have been born with white wings. Early in life, the black- and white-winged beetles seem to be very similar in number of mating events, eggs laid, and survival rates, but shortly after laying their eggs the white beetles die and there are only black-winged beetles during the late fall. Which of the following is a true statement about the beetles?
13. The Hardy-Weinberg model makes assumptions that never happen in real populations, yet the model is useful because:
14. Three-spined stickleback fish (Gasterosteus aculeatus) show substantial heritable variation in gill-raker length related to differences in their diets. Longer gill rakers appear to function better for capturing open-water prey, while shorter gill rakers function better for capturing shallow-water prey. Which of the following types of selection is most likely to be found in a large lake (open water in the middle and shallow water around the sides) with a high density of these fish?
15. Over long periods of time, many cave-dwelling organisms have lost their eyes. Tapeworms have lost their digestive systems. Whales have lost their hind limbs. How can natural selection account for these losses? A. Natural selection cannot account for losses, but accounts only for new structures and functions. B. Natural selection accounts for these losses by the principle of use and disuse. C. Under particular circumstances that persisted for long periods, each of these structures presented greater costs than benefits. D. The ancestors of these organisms experienced harmful mutations that forced them to lose these structures.