Exam 3 Flashcards
Which of the following is considered a scenario leading to sexual dimorphism in animals?
A) different life histories and ecological relationships of males and females
B) sexual selection mediated by contests among males for access to females
C) sexual selection mediated by direct exercise of female mate choice
D) all of the above
D) all of the above
You are studying a species of bird that is often monogamous but sometimes exhibits polygyny. You have the choice of studying this species in several different habitats. Which of the following will you choose if you want the highest likelihood of finding polygyny?
A) a habitat in which territory qualities are nearly identical
B) a habitat in which territory qualities vary somewhat
C) a habitat in which territory qualities are highly variable
D) a habitat unsuitable for the formation of territories
C) a habitat in which territory qualities are highly variable
In species with separate sexes, which sex can enhance more its evolutionary fitness by mating with many partners of the opposite sex?
A) males B) females C) Neither sex has an advantage in this respect.
A) males
Of the two possible kinds of polygamy, which is by far the more common in animals?
A) polygyny (one male forms long-term bonds with more than one female)
B) polyandry (one female forms long-term bonds with more than one male)
A) polygyny (one male forms long-term bonds with more than one female)
What happened when the tails of male widowbirds were artificially elongated?
A) These males were more successful in attracting mates than males with normal tails.
B) These males were less successful in attracting mates than males with normal tails.
C) These males were about equally successful in attracting mates as males with normal tails.
A) These males were more successful in attracting mates than males with normal tails.
American woodcocks have a promiscuous mating system. Male woodcocks gather in a communal display ground called a “lek”. They engage in an elaborate and conspicuous display flight called “winnowing,” as they vie for matings with their female spectators. This mating ritual performed by the males is likely the result of sexual selection, but which kind of sexual selection is it?
A) direct exercise of mate choice by females
B) contests among males for access to females
A) direct exercise of mate choice by females
Flocking behavior in European goldfinches has costs and benefits. Which of the following would be considered a cost associated with increasing flock size?
A) fewer head jerks per minute for individuals
B) increased total vigilance rate for the entire flock
C) reduced food handling time for individuals
D) increased flight time between food plants for individuals caused by more rapid resource depletion
D) increased flight time between food plants for individuals caused by more rapid resource depletion
A crow attacks a red-tailed hawk flying nearby. Which of these two birds is the donor of the attacking behavior?
A) the crow
B) the red-tailed hawk
A) the crow
Which of the following kinds of behavior is least likely to be favored by natural selection under any circumstance? A) cooperative B) altruistic C) selfish D) spiteful
D) spiteful
If C is the cost of a particular behavior for the donor, B is the benefit of the behavior to the recipient, and r is the coefficient of relationship, what does the relationship C
C) conditions under which an altruistic behavior will increase in the population
The famous evolutionary biologist J. B. S. Haldane said the following one evening while drinking at a pub: “I would jump into a river and risk my life to save two brothers, but not one. I would jump in to save eight cousins, but not seven.” To what important concept was he alluding?
A) An altruistic behavior does not begin to make evolutionary sense until the inclusive fitness associated with the behavior (from the donor’s perspective) is at least zero.
B) His rambling comments were clearly the product of intoxication and had no meaningful evolutionary interpretation.
A) An altruistic behavior does not begin to make evolutionary sense until the inclusive fitness associated with the behavior (from the donor’s perspective) is at least zero.
Effective population size (Ne) is almost always lower than actual population size (N) because, for example:
A. sex ratios are equal
B. breeding systems are typically monogamous
C. family sizes vary, with some parents contributing more offspring
D. environmental conditions are constant
C. family sizes vary, with some parents contributing more offspring
The number of alleles per gene, for example the number of MHC alleles in human populations, describes a measure of:
A) different life histories and ecological relationships of males and females
B) sexual selection mediated by contests among males for access to females
C) sexual selection mediated by direct exercise of female mate choice
D) all of the above
A) different life histories and ecological relationships of males and females
The number of alleles per gene, for example the number of MHC alleles in human populations, describes a measure of: A. inbreeding B. natural selection C. genetic diversity D. outbreeding depression
C. genetic diversity
Why are cheetahs an example of how low genetic diversity does not necessarily mean the population is headed for extinction?
A. While the genetic diversity continues to decline, there is no evidence of inbreeding depression.
B. The genetic diversity, while low, is not declining in part because females mate with many males.
C. They evolved with low genetic diversity to begin with, so they have adapted to it.
D. none of the above
B. The genetic diversity, while low, is not declining in part because females mate with many males.
What is an extinction vortex?
A. the random decline of a population even if they have high genetic diversity
B. the inevitable trajectory of all species
C. a description of the self-reinforcing decline of large populations
D. the loss of genetic diversity, lowering fitness, which further reduces the population size
D. the loss of genetic diversity, lowering fitness, which further reduces the population size
In the absence of natural selection, genetic drift will cause alleles to become fixed or lost most rapidly in the population(s) of which size? A. 4 B. 40 C. 400 D. 4000 E. all of the above
A. 4
In experiments with the plant Banksia spinulosa, Australian researchers Glenda Vaughton and Susan Carthew showed that individual plants:
A) can make distinctions among developing embryos on the basis of their genotypes.
B) cannot make distinctions among developing embryos on the basis of their genotypes.
A) can make distinctions among developing embryos on the basis of their genotypes.
A small population of wolves founded by a single breeding pair on the Scandinavian peninsula in 1983 showed little vitality until 1991, when the population began to grow exponentially. What event in 1991 led to the increased vitality of the population?
A) several years of unusually mild winters
B) infusion of new genes into the pack by a single immigrant male
C) cessation of hunting by humans
D) recovery of the Scandinavian caribou herd
E) all of the above
B) infusion of new genes into the pack by a single immigrant male
As illustrated in the research conducted by Price and Wasser on Delphinium nelsoni, (Figure 13.15, above) outbreeding is always desirable, even if matings occur between individuals separated by great distance.
A) True B) False
B) False
