I’m stuck on a Psychology question and need an explanation.
Chapter 8 Questions:
Females of many African cichlid fish lay their eggs on lake bottoms in depressions made by males. The females brood their eggs and young fry in their mouths. A female picks up her orange eggs almost as quickly as she lays them. As this happens, the male cichlid that made the “nest” may move in front of her and spread his anal fin, which in many species is decorated with a line of large orange spots. The female may try to pick up the objects on the fin. As she does, the male releases his sperm, some of which swim into the female’s mouth, where they fertilize her eggs (Egger et al. 2011). If sensory exploitation explains the evolutionary origin of the female’s behavior, what prediction can you make about how female fish of a related species will respond to the normally unspotted anal fins of males that have been painted with colorful egg-like spots?
.2 In studying the courtship behavior of the empid flies, E. L. Kessel was amazed to find a species, Hilara sartor, in which males gather together to hover in swarms, carrying empty silken balloons, which females accept prior to mating with balloon-carrying males (Kessel 1955). Use the concept of a co-opted, preexisting sensory system to explain how this sort of behavior could have originated. You should know that many empid flies are predatory and that males often offer their mates a prey item as an inducement to mate. In one species of this sort, some males supply their mates with an inedible dandelion-like tufted seed (LaBas and Hockman 2005).
Chapter 9 Questions:
1. Female satin bowerbirds (Ptilonorhynchus violaceus) appear to favor males that give very intense, even aggressive, courtship displays. Perhaps that is why females are often “jumpy” when in the presence of a displaying male. Males differ in how they adjust their displays in response to the female’s reaction. Females that often flinch as the male displays tend to leave the site without mating, whereas females that crouch down in the male’s bower are more likely to stay and mate with the displaying male. Why might these observations have led Gerald Borgia and colleagues to hypothesize that the bower enables females to protect themselves against forced copulation attempts by displaying males (Patricelli et al. 2002)? How could males gain by making it harder for themselves to force females to mate? See Patricelli et al.
2. Male rats, sheep, cattle, rhesus monkeys, and humans that have copulated to satiation with one female are speedily rejuvenated if they gain access to a new female. This phenomenon is called the Coolidge effect, supposedly because when Mrs. Calvin Coolidge learned on a farm tour that roosters copulate dozens of times each day, she said, “Please tell that to the president.” When the president was told, he asked his guide, “Same hen every time?” Upon learning that roosters select a new hen each time, he said, “Please tell that to Mrs. Coolidge.” Provide a sexual selectionist hypothesis for the evolution of the Coolidge effect. Use your hypothesis to predict what kinds of species should lack the Coolidge effect.
3. Gene-centered thinking tells us that sexual reproduction is a Darwinian puzzle in and of itself. Why? Consider the fitness consequences for asexual (i.e., parthenogenetic) females in competition with sexual ones in a given population in which both types produce equal numbers of offspring. When you have dealt with this problem, you should be surprised to learn that in many aphids, females are perfectly capable of cloning themselves, which occurs in one generation after another before one group of females produces a generation of both sons and daughters; these males and females then engage in sexual reproduction before their descendants resume cloning themselves (Moran and Dunbar 2006). What is the Darwinian puzzle here?