12/13/23, 5:43 PM Midterm Answer Key: BIO220H1 S LEC0101 20211:From Genomes to Ecosystems in a Changing World
Midterm Answer Key
Based on the results of Professor Marla Sokolowski’s research on fruit flies, which statement about
the rover/sitter polymorphism in fruit flies is FALSE?
A. There are genetic effects on foraging behaviour.
B. Foraging behaviour can be altered by environmental conditions.
C. Sitters show plasticity, but rovers show no plasticity in foraging behaviour.
D. If mated, a sitter male and a sitter female would produce all sitter offspring.
You want to perform a selection experiment on female traits associated with mating in an insect.
Which of the following treatments should INCREASE the strength of sexual selection in females?
A. Making sure the males and females are roughly the same age
B. Excluding any predators from the environment
C. Providing abundant resources in the environment
D. Skewing the adult sex ratio by including more females than males in groups
Based on the required reading, “Mating Systems in Sexual Animals”, which scenario would be MOST
LIKELY to lead to polygyny?
A. Females control resources
B. Males provide defense for females
C. Males provide substantial parental care to offspring
D. The sex ratio is heavily male biased (i.e., more males than females)
In which of the following examples from our lectures is it MOST LIKELY that female choice evolved
because of direct benefits to the female?
A. The peacock
B. The pipefish
C. The katydid
D. The bowerbird
Based on Brennan’s article, “Sexual Selection”, which of the following is NOT an example of
intersexual conflict?
A. Intimidation and sexual harassment in red deer
B. Morphological traits in female beetles that prevent sperm from contacting eggs directly
C. Traumatic insemination of bedbugs
D. Grasping traits of waterstriders
Azar’s family consists of (i) a genetically-identical twin, (ii) a younger sister, (iii) an uncle, and (iv) a
cousin. According to Hamilton’s Rule, if b = 3 and c = 1, Azar should cooperate with how many family
, 12/13/23, 5:43 PM Midterm Answer Key: BIO220H1 S LEC0101 20211:From Genomes to Ecosystems in a Changing World
members?
A. 1
B. 2
C. 3
D. 4
Based on what you have learned about the costs and benefits of provisioning, which of the following
is MOST LIKELY to DECREASE the strength of parent-offspring conflict?
A. Increased relatedness between siblings
B. Reduced mating opportunities for males relative to females
C. An increased probability that parents will survive to reproduce again
D. Female parental care rather than male parental care
Of the following four traits – (i) long tails of widowbirds, (ii) bee hives, (iii) ‘death grip’ behaviour of
Ophiocordyceps-infected ants, and (iv) turtle shells – how many would Richard Dawkins consider to
be ‘extended phenotypes’?
A. 1
B. 2
C. 3
D. 4
What is the key evolutionary conclusion from this figure, modified from Graham et al. (1990)?
A. Immune responses may have evolved to operate best under warmer (i.e., fever)
temperatures *
Midterm Answer Key
Based on the results of Professor Marla Sokolowski’s research on fruit flies, which statement about
the rover/sitter polymorphism in fruit flies is FALSE?
A. There are genetic effects on foraging behaviour.
B. Foraging behaviour can be altered by environmental conditions.
C. Sitters show plasticity, but rovers show no plasticity in foraging behaviour.
D. If mated, a sitter male and a sitter female would produce all sitter offspring.
You want to perform a selection experiment on female traits associated with mating in an insect.
Which of the following treatments should INCREASE the strength of sexual selection in females?
A. Making sure the males and females are roughly the same age
B. Excluding any predators from the environment
C. Providing abundant resources in the environment
D. Skewing the adult sex ratio by including more females than males in groups
Based on the required reading, “Mating Systems in Sexual Animals”, which scenario would be MOST
LIKELY to lead to polygyny?
A. Females control resources
B. Males provide defense for females
C. Males provide substantial parental care to offspring
D. The sex ratio is heavily male biased (i.e., more males than females)
In which of the following examples from our lectures is it MOST LIKELY that female choice evolved
because of direct benefits to the female?
A. The peacock
B. The pipefish
C. The katydid
D. The bowerbird
Based on Brennan’s article, “Sexual Selection”, which of the following is NOT an example of
intersexual conflict?
A. Intimidation and sexual harassment in red deer
B. Morphological traits in female beetles that prevent sperm from contacting eggs directly
C. Traumatic insemination of bedbugs
D. Grasping traits of waterstriders
Azar’s family consists of (i) a genetically-identical twin, (ii) a younger sister, (iii) an uncle, and (iv) a
cousin. According to Hamilton’s Rule, if b = 3 and c = 1, Azar should cooperate with how many family
, 12/13/23, 5:43 PM Midterm Answer Key: BIO220H1 S LEC0101 20211:From Genomes to Ecosystems in a Changing World
members?
A. 1
B. 2
C. 3
D. 4
Based on what you have learned about the costs and benefits of provisioning, which of the following
is MOST LIKELY to DECREASE the strength of parent-offspring conflict?
A. Increased relatedness between siblings
B. Reduced mating opportunities for males relative to females
C. An increased probability that parents will survive to reproduce again
D. Female parental care rather than male parental care
Of the following four traits – (i) long tails of widowbirds, (ii) bee hives, (iii) ‘death grip’ behaviour of
Ophiocordyceps-infected ants, and (iv) turtle shells – how many would Richard Dawkins consider to
be ‘extended phenotypes’?
A. 1
B. 2
C. 3
D. 4
What is the key evolutionary conclusion from this figure, modified from Graham et al. (1990)?
A. Immune responses may have evolved to operate best under warmer (i.e., fever)
temperatures *
