1)Below are two histograms showing guppy coloration in two different streams, Stream North and Stream South. Use these histograms to answer the first two questions.
Q1. Which spot brightness level is most heavily represented in Stream North?
Q2. In which stream is average spot brightness highest: Stream North or Stream South?
Stream North.
Stream South.
Q3. Darwin's theory of natural selection is based on which of the following assumptions? (Check all that apply.)
Variability
Inheritance
Differential survival
Sexual reproduction
Q4. Which of the following options best summarizes Endler's greenhouse pond experiment? Variation in adult male coloration among ponds was due to:
The populations initially having different coloration.
Differences in the hunting patterns of predators.
The loss of spots in some populations due to a mutation.
Variable preferences by female guppies causing divergent sexual selection.
Q5. Fill in the blanks in the following sentence by selecting an option from below. Cichlids tend to prey on ______________ guppies, while Rivulus mainly prey on _____________ guppies.
Adult; juvenile
Juvenile; adult
Male; female
Female; male
Q6. Which of the following locations was not indicated as part of the natural range of guppies, Poecilia reticulata?
Venezuela.
Trinidad.
Tobago.
Columbia.
Q7. In Endler's study, after 20 months, what was the average number of spots on fish in the control pond?
10
11
12
13
Q8. Which of the following best describes the change in coloration observed in male guppies?
A mutation in the male guppies occurred when predators were present.
The male guppies change their coloration when they see a predator.
Male guppies with more showy coloration tend to be eaten more often.
When females are in the presence of predators, they tend to give birth to less showy male guppies.
Q9. Imagine a different system in which toads had a wide range of variation in color. In some ponds, most of the toads are light in color. In other ponds, the average color is fairly dark. From the options below, select which represent TESTABLE hypotheses that could explain this difference in coloration. (Check all that apply.)
A predator that is present in some ponds prefers one color to the other.
Female toads in some ponds prefer darker toads, while females in another pond prefer lighter toads.
Toad color is determined by food quality, which varies pond to pond.
Toads can change their color, based on their stress level.
Q10. An evolutionary biologist studying the toads in Question 9 hypothesizes that female toads prefer like-colored mates, and this preference maintains observed variation in toad color among ponds. Such mating is called assortative; in this case it would mean that light-colored females prefer light-colored males, and dark-colored females prefer dark-colored males.
The biologist has already determined that color is highly heritable for these toads. She rears toads in experimental tanks with no predators, over many generations, holding food quality constant. Which observation below best REFUTES her hypothesis?
A tank initially containing light and dark toads of both genders eventually contains only dark toads.
A tank initially containing light-colored females and males of both colors eventually contains only dark toads.
A tank initially containing dark-colored females and males of both colors eventually contains only dark toads.
A tank initially containing light-colored females and dark-colored males eventually contains toads of intermediate coloration.