Blog

*Refer to the previous question (32) for prompt* Compute the Frequency of this schedule. Please show your work: (3 points)

Based on the biological definition of sex, what is the single character that distinguishes males from females?

Which statement is true about sexual selection?

Which of the following are required for the evolution of reciprocal altruism? Select two correct answers.

Following selection, 80% of individuals with the “AA” genotype survive, all “Aa” individuals survive and 40% of “aa” individuals survive. Their respective relative fitnesses are…

Blue-headed wrasse fish are born as biological “females”, but change into biological “males” when they grow to a certain size. This switch is the result of fitness differences between “males” and “females” at different stages of development. Large individuals are better able to defend nesting sites from competitors, so fitness is higher in “males” that are larger. Which of the following graphs illustrates the relationship between size and fitness in the two sexes of blue-headed wrasse?

Some dinosaurs had small, fluffy feathers called “downy” feathers (similar to down feathers in a pillow), but lacked the type of feathers necessary for flight. These dinosaurs are believed to be the ancestors of modern birds, which have several types of feathers that allow them to fly.  How can we explain the evolution of an “intermediate” trait such as downy feather, if they were functionally useless for flight?

Origin of life experiments by Miller, Urey, and others (Miller-Urey Experiments) involved circulating a mixture of simple gases (a simulated reducing atmosphere) past an energy source such as a spark in an enclosed glass apparatus. Results of these experiments showed that

Prior to European colonization, tens of thousands of whooping cranes lived in North America. By 1938, due to overexploitation and habitat loss, whooping cranes were virtually extinct, with a total population of only 15 individuals. Since then, careful conservation efforts have increased the North American whooping crane population to over 800 today. From a genetic standpoint, as a result of this catastrophe, whooping cranes experienced a “population bottleneck”, which is a severe form of [answerA]. The current population of whooping cranes should be expected to have [answerB], relative to the pre-colonial population.

Which of the following is NOT one of the hypotheses that underly Darwin’s theory of Evolution by natural selection?