Exam 3 questions

Question 1

In which game are players strategies fixed?

• Hawk-Dove
• Tit for Tat
• Prisoner’s Dilemma
• Raider’s Dilemma

Answer 1

Hawk-Dove

Question 2

A species interaction in which two organisms live in close association with each other is:

• Symbiosis
• Mutualism
• Cooperation
• Holobiont

Answer 2

Symbiosis

Question 3

If you were playing Tit-for-Tat, and your partner cheated, what would be your next move and why?

• Betray, because you are “provocable”
• Betray, because you forgive
• Cooperate, because you forgive
• Cooperate, because you are “provocable”

Answer 3

Betray, because you are “provocable”

Question 4

Calculate relatedness in a diploid system of an offspring to their paternal aunt:

• 0.050
• 0.250
• 0.125
• 0.350

Answer 4

0.250

Question 5

Eusociality is always driven by a haplodiploid genetic system.

• True
• False

Answer 5

False

Question 6

In a haplodiploid system, calculate the relatedness of a son to a maternal aunt.

• 0.25
• 0.375
• 0.5
• 0.75

Answer 6

0.375

Question 7

If the Geographic Mosaic of Co-evolution is occurring, what would you expect to see when you looked at populations of two interacting species:

• All populations act as parasites at all times
• All populations are acting as mutualists at one point in time, and all populations are acting as parasites at the next point in time
• At any given point in time some populations are acting as mutualists, and some populations are acting as parasites
• All populations act as mutualists at all times

Answer 7

At any given point in time some populations are acting as mutualists, and some populations are acting as parasites

Question 8

Co-evolution can be driven by:

• Antagonistic interactions
• Neutral interactions
• Both antagonistic and mutualistic interactions
• Mutualistic interactions

Answer 8

Both antagonistic and mutualistic interactions

Question 9

In a haplodiploid system, calculate a) the relatedness of a maternal aunt (sister to the mother) to a focal daughter , b) the relatedness of a paternal aunt (sister to the father) to a focal daughter , and c) determine which aunt (answer maternal or paternal) is most likely to help raise the focal daughter .

Answer 9

A. 0.375 B. 0.25 C. Maternal

Question 10

Is the following statement true or false about Evolutionary Stable Strategies (ESS)? ESS can be beaten when it is a common strategy and a new strategy enters the system.

• True
• False

Answer 10

False

Question 11

When is Hamilton’s Rule NOT likely to be true?

• Relatedness is low
• Relatedness is high
• Costs of altruism to the altruist are low
• Benefits of altruism to the recipient are high

Answer 11

Relatedness is low

Question 12

What type of mutualism do ectomycorrhizal fungi and plant roots have?

• Defensive mutualism
• Trophic mutualism
• Dispersive mutualism

Answer 12

Trophic mutualism

Question 13

In game theory, which of the following makes the “prisoner’s dilemma” game different from the “hawk-dove” game?

• Identifies an optimal strategy
• Strategies are fixed
• Strategies are dynamic (not fixed)

Answer 13

Strategies are dynamic (not fixed)

Question 14

True or False. HOX genes within a species rapidly acquire and fix mutations each generation to ensure the greatest phenotypic diversity and responsiveness to dynamic external conditions.

Answer 14

False

Question 15

The characteristics identified in the figure are examples of

• homeotic transformations
• evo–devo.
• homeobox genes.
• ontogeny.

Answer 15

homeotic transformations.

Question 16

According to the two major discoveries of evolutionary biology which of the following are true?

• Small genetic changes can have big phenotypic consequences
• Regulation of the expression of genes involved in development rarely affect phenotype
• Genetic changes that alter protein sequence(s) are generally beneficial
• Highly phenotypically distinct organisms show incredible levels of functional conservation in gene products that direct development
• None of the available answers

Answer 16

Small genetic changes can have big phenotypic consequences

Highly phenotypically distinct organisms show incredible levels of functional conservation in gene products that direct development

Question 17

MADS-box genes affect

• segmentation in animals.
• lateral lines in fish.
• fruit fly development.
• plant leaves, roots, and flowers.

Answer 17

plant leaves, roots, and flowers.

Question 18

Which of the following cell types would you expect to be totipotent?

• blood stem cells that can become various types of blood cells
• germ line cells
• embryonic cells early in development
• brain cells

Answer 18

embryonic cells early in development

Question 19

Based on the Davidson and Erwin paper that we read in class, match the gene regulatory network component with the correct description A.) Kernals B.)Plug-Ins C.) Differentiation gene batteries

Small subcircuits of the GRN that have been repeatedly coopted to diverse developmental purposes.

evolutionarily inflexible subcircuits that perform essential upstream functions in building given body parts.

protein coding genes under common regulatory control, the products of which execute cell type-specific functions.

Answer 19

Kernels - evolutionarily inflexible subcircuits that perform essential upstream functions in building given body parts.

Plug-ins - Small subcircuits of the GRN that have been repeatedly coopted to diverse developmental purposes.

Differentiation gene batteries - protein coding genes under common regulatory control, the products of which execute cell type-specific functions.

Question 20

Based on the Davidson and Erwin paper that we read in class, is it true that the most frequent and least constrained kinds of change will occur in the peripheral regions of the “gene regulatory netowrk” (i.e., within differentiation gene batteries themselves and the apparatus that controls their deployment)?

• True
• False

Answer 20

True

Question 21

Evolution of Darwin’s finches and their beaks

Date:February 11, 2015

Source:Uppsala University

Darwin’s finches are a classical example of an adaptive radiation. Their common ancestor arrived on the Galapagos about two million years ago. During the time that has passed the Darwin’s finches have evolved into 15 recognized species differing in body size, beak shape, song and feeding behaviour. Changes in the size and form of the beak have enabled different species to utilize different food resources such us insects, seeds, nectar from cactus flowers as well as blood from iguanas, all driven by Darwinian selection.

“We have now sequenced 120 birds including all known species of Darwin’s finches, as well as two closely related species in order to study their evolutionary history,” explains Sangeet Lamichhaney PhD student and shared first author on the paper. Multiple individuals of each species were analyzed and for some species birds from up to six different islands were sampled to study variation within and between islands.

One important insight was that gene flow between species has played a prominent role throughout the evolutionary history of the Darwin’s finches. The scientists could even trace clear signs of hybridization between a warbler finch and the common ancestor of tree and ground finches that must have occurred about a million year ago.

The most striking phenotypic diversity among the Darwin’s finches is the variation in the size and shape of the beaks. Charles Darwin was struck by this biological diversity, and compared it with the variety he was accustomed to among European birds such as the hawfinch, the chaffinch and warblers, as documented in his book “The Voyage of The Beagle.” The team investigated the genetic basis for variation in beak shape by comparing two species with blunt beaks and two species with pointed beaks. Fifteen regions of the genome stood out as being very different in this contrast, and as many as six of these contained genes that previously have been associated with craniofacial and/or beak development.

“The most exciting and significant finding was that genetic variation in the ALX1 gene is associated with variation in beak shape not only between species of Darwin’s finches but also among individuals of one of them, the medium ground finch,” explains Leif Andersson, Uppsala University, Swedish University of Agricultural Sciences and Texas A&M University, who led the study.

“This is a very exciting discovery for us since we have previously shown that beak shape in the medium ground finch has undergone a rapid evolution in response to environmental changes. Now we know that hybridization mixes the different variants of an important gene, ALX1,” says Rosemary Grant.

The ALX1 gene codes for a transcription factor with a crucial role for normal craniofacial development in vertebrates, and mutations that inactivate this gene cause severe birth defects including frontonasal dysplasia in humans.

“This is an interesting example where mild mutations in a gene that is critical for normal development leads to phenotypic evolution,” comments Leif Andersson.

“I would not be surprised if it turns out that mutations with minor or minute effects on ALX1 function or expression contribute to the bewildering facial diversity among humans,” says Leif Andersson.

• Polymorphisms in ALX1 giving rise to adaptive beak morphologies have occurred prior to the emergence of reproductive isolating mechanisms
• Gene duplication in ALX1 resulted in an expansion of the gene regulatory network involved in beak morphologies
• ALX1 is a likely a ‘kernel’-level component of the gene regulatory network involved in beak morphology
• ALX1 is likely present in all finches

Answer 21

Polymorphisms in ALX1 giving rise to adaptive beak morphologies have occurred prior to the emergence of reproductive isolating mechanisms

ALX1 is likely present in all finches

Question 22

Which of the following is not true about the field of Evo Devo (aka Evolutionary Developmental Biology)

• Evo devo has discovered extensive similarities in gene regulation among distantly related species with fundamentally different body plans
• Evo Devo utilizes a population genetic approach to studying evolution
• Evo Devo investigates the evolution of the genetic machinery of development
• A large part of Evo Devo research is focused on the evolution of genetic toolkits

Answer 22

Evo Devo utilizes a population genetic approach to studying evolution

Question 23

True or False: Modern evolutionary biologists still accept Haeckel’s “Biogenetic Law” from the mid-1800s that claims developing animal embryos undergo a chronological replay of their species’ past evolutionary forms (ontogeny recapitulates phylogeny) and that evolution only occurs on features that manifest in the later developmental stages.

Answer 23

False

Question 24

In the field of Evo Devo, biologists have discovered strong conservation of gene order and coding DNA sequence in certain gene families involved in development (e.g., HOX genes) among widely divergent taxonomic groups (e.g., fishes vs. birds). The conservation of these genes is due to which of the following:.

• strong pleiotropic effects associated with changes in these developmental genes
• weak pleiotropic effects associated with changes in these developmental genes
• no pleiotropic effects associated with changes in these developmental genes

Answer 24

strong pleiotropic effects associated with changes in these developmental genes

Question 25

According to the concept of punctuated equilibrium:

• Many new species arise rapidly followed by a long period of none to little species diversification
• Species change gradually and continually over millions of years
• The most common evolutionary trend is an increase in size
• Life has become progressively more complex

Answer 25

Many new species arise rapidly followed by a long period of none to little species diversification

Question 26

Chlamydomonas are _______ while Volvox are ________.

Answer 26

unicellular / multicellular

Question 27

A somatic cell is

• a cell that has four membranes around it.
• one of the cells that produces spores in slime mold–fruiting bodies.
• a cell specialized for reproduction.
• a body cell that is responsible for growth and maintenance.

Answer 27

a body cell that is responsible for growth and maintenance.

Question 28

Which of the following statements regarding complexity is true?

• Highly complex structures, like eyes or limbs, can be gained or lost as species evolve
• Eukaryotic organisms (e.g. penguins) are no more complex than marine sponges
• Modern bacteria and archaea are vastly more complex than their ancestors.
• Evolution always progresses toward greater complexity.

Answer 28

Highly complex structures, like eyes or limbs, can be gained or lost as species evolve

Question 29

True or False. All life has a tendency to progress towards greater complexity

Answer 29

False

Question 30

Which of the following major transitions proposed by John Maynard Smith and Eörs Szathmary (1997) most likely occurred first?

• the evolution of groups, including complex societies
• the origin of the first cells
• the emergence of eukaryotic cells
• the evolution of sexual reproduction

Answer 30

the origin of the first cells

Question 31

What is the earliest known catalytic and information transmitting biomolecule?

• Proteins
• DNA
• Deoxynucleotides
• Ribozyme

Answer 31

Ribozyme

Question 32

Looking at the figure, how many times has multicellularity evolved?

• twice
• at least six times
• three times
• once

Answer 32

at least six times

Question 33

Fill in the blanks to correctly complete this sentence

____________________asserted that all life has a ‘tendency’ to become more complex, which moves them ‘up’ a ladder of progress and towards greater complexity, which______________ rejected, stating that ‘there is no theoretical reason to expect evolutionary lineages to increase in complexity with time, and no empirical evidence that they do so.’

Answer 33

Lamarck / Maynard smith

Question 34

You are studying four lineages of frogs and find that all of these lineages arose during the Cenozoic. Only one of the four lineages contains some species adapted to temperate regions. What species richness pattern hypothesis does this support?

• Diversification Rate Hypothesis
• Climatic Stability Hypothesis
• Time and Area Hypothesis
• Climatic Harshness Hypothesis
• Species Energy Hypothesis

Answer 34

Time and Area Hypothesis

Question 35

What discoveries in the K-T boundary soil led to our understanding of how the K-T extinction event occurred?

• Iridium and shocked quartz indicated a large impact and/or volcanic activity
• High levels of CO2 that suggests elevated sea levels
• Large amounts of soot suggested the atmosphere was clear

Answer 35

Iridium and shocked quartz indicated a large impact and/or volcanic activity

Question 36

Which of the following is not a proven method of increasing your likelihood of going extinct?

• Having a low trophic position
• Having a low genetic diversity
• Having a specialized diet
• Having a small population size

Answer 36

Having a low trophic position

Question 37

Which of the following arguments about the validity of resurrecting extinct species (e.g., dodo bird, Tasmanian tiger, passenger pigeon) makes the least sense using principles from evolutionary biology?

• The effective-population size of the resurrected species would likely be low, which would constrain future adaptations because random genetic drift has a chance of being a stronger evolutionary force than natural selection.
• The resurrection of extinct species is risky because other ecologically-associated species have not stopped evolving (e.g., wooly mammoth and the plant species that they feed on) and therefore the resurrected species may no longer be well adapted to these ecological associations.
• Hybridization with other closely related species can lead to massive introgression (swamping) of non-adaptive genetic variation into the resurrected species.
• Hybridization with other closely related species will always result in a decrease of genetic variation in the hybrid offspring.

Answer 37

Hybridization with other closely related species will always result in a decrease of genetic variation in the hybrid offspring.

Question 38

Which of the following arguments about the conservation value of human-mediated environments (urban or agricultural) makes the least sense using principles from evolutionary biology?

• Human-commensal species have unique adaptations that allow them to live successfully around humans
• Urban environments are fragmented from each other by agricultural lands or natural areas, which may limit gene flow in species that are strictly adapted to an urban environment.
• Urban environments don’t possess novel ecological niches or novel ecological interactions that can lead to new adaptations by species.
• The rapid pace that human-mediated environments are expected to change threatens species because new advantageous mutations may not arise fast enough that would allow species to adapt.

Answer 38

Urban environments don’t possess novel ecological niches or novel ecological interactions that can lead to new adaptations by species.

Question 39

What physical features of the first hominins are more like the panin lineage rather than the hominin lineage?

• skull orientation, dental anatomy
• small cranial capacity, opposable big toe
• larger cranial capacity, fully bipedal locomotion
• smaller braincase, dental anatomy

Answer 39

small cranial capacity, opposable big toe

Question 40

In the figure, each horizontal box represents a separate species. Based on this figure,

• Homo sapiens was a contemporary of Paranthropus boisei
• Homo sapiens and H. floresiensis were not contemporaries
• Homo habilis and Paranthropus robustus were likely contemporaries
• Australopithecus platyops preceded Sahelantropus tchadensis

Answer 40

Homo habilis and Paranthropus robustus were likely contemporaries

Question 41

In the figure, each horizontal box represents a separate species. Based on this figure,

• the multiregional hypothesis is supported.
• there has been only a single hominin species for most of the evolutionary history of humans.
• the out-of-Africa hypothesis is supported.
• many hominin species coexisted during most of the evolutionary history of humans.

Answer 41

many hominin species coexisted during most of the evolutionary history of humans.

Question 42

Which is NOT true of lactose tolerance in humans?

• It is thought to be an adaptation to the domestication of large mammals
• It is the result of the persistence of the enzyme “lactase”
• It is caused by mutations in the genetic “switch” MCM6
• It is only present in individuals with (at least some) European ancestry

Answer 42

It is only present in individuals with (at least some) European ancestry

Question 43

How do Neanderthals physically differ from modern humans?

• Neanderthals were lighter and faster, with a more pronounced brow ridge and larger eyes.
• Neanderthals were significantly shorter and stockier, with large feet that lacked a raised arch.
• Neanderthals were heavier, stronger, and stockier, with a more pronounced brow ridge and larger eyes.
• Neanderthals were significantly shorter, with large feet that lacked a raised arch and a flat face with reduced dentition.

Answer 43

Neanderthals were heavier, stronger, and stockier, with a more pronounced brow ridge and larger eyes.

Question 44

Which of the following arguments about human evolution makes the least sense using principles from evolutionary biology?

• All geographically distinct human populations share a common ancestor at some point in their evolutionary past.
• Admixture (genetic mixing) between different human groups is known to have occurred throughout human evolution and thus many human groups have not evolved in complete isolation.
• Modern humans have an effective-population size that is at least an order of magnitude larger than their census-population size.
• Even though there are some adaptive genetic differences between geographically distinct human groups (e.g., lactase gene), a majority of the human genome does not differ between human groups.

Answer 44

Modern humans have an effective-population size that is at least an order of magnitude larger than their census-population size.

Question 45

The physical size difference between most multicellular hosts and their pathogens results in which of the following evolutionary advantages for the pathogen?

• Pathogens have lower mutation rates than hosts, resulting in more stable populations.
• Hosts evolve more rapidly due to mutations induced by the pathogen.
• Pathogens have larger population sizes and shorter generation times than hosts, allowing for increased rates of adaptation.
• Host population sizes increase in the presence of a pathogen, providing more potential hosts for infection.

Answer 45

Pathogens have larger population sizes and shorter generation times than hosts, allowing for increased rates of adaptation.

Question 46

In the survivorship curve shown in the figure, imagine an early acting mutation that increases survivorship between days 0 and 30 and a late-acting mutation that increases survivorship between days 150 and 180. Natural selection will act

• more strongly on the late-acting mutation.
• on both mutations the same.
• on neither mutation.
• more strongly on the early acting mutation.

Answer 46

more strongly on the early acting mutation.

Question 47

The fact that both endothermic and exothermic vertebrates induce fever, by different mechanisms, in response to infection supports which of the following hypotheses?

• Fever evolved by genetic drift.
• All vertebrates are susceptible to infection by the same pathogens.
• Fever is adaptive; it may somehow be advantageous in dealing with infection.
• Vertebrates do not experience a coevolutionary arms race with pathogens.

Answer 47

Fever is adaptive; it may somehow be advantageous in dealing with infection.

Question 48

All of the following are evolved immune defenses that attempt to isolate pathogens, minimize the harm they cause, and remove them from the body of the life form (any species), EXCEPT ________ systems.

• bacterial restriction modification
• viral reverse transcription
• vertebrate adaptive immune
• plant innate immunity

Answer 48

viral reverse transcription

Question 49

How can age-specific antagonistic pleiotropy account for senescence?

• An allele that confers benefits at a young age might be favored even if it is deleterious at a later age.
• Mutations that occur early in life are likely to produce more mutations later in life.
• Early acting mutations are acted on more strongly by selection than late-acting mutations.
• Alleles that confer benefits early in life also tend to confer benefits later in life.

Answer 49

An allele that confers benefits at a young age might be favored even if it is deleterious at a later age.

Question 50

Which of the following arguments about applying evolutionary biology to human health and disease makes the least sense using principles from evolutionary biology?

• Evolutionary medicine asks why natural selection has left humans with traits that make them vulnerable to disease
• Diseases are adaptations shaped by selection.
• Sexual selection shapes traits that result in different health risks between sexes.
• Any of the following evolutionary forces (natural selection, genetic drift, mutation, and migration) can potentially be important for understanding traits and disease.
• Coevolution among species can influence health and disease (e.g. evolutionary arms races and mutualistic relationships such as those seen in the microbiome).

Answer 50

Diseases are adaptations shaped by selection.