BZ 220 Quizzes

Gregor Mendel

Darwin was inspired and guided by the work of many scientists when formulating his ideas about evolution and natural selection. Which thinker did NOT influence Darwin?

Option 2

Large female meadow voles living in a stable environment with very few predators are able to produce larger offspring with a higher chance of survival compared to small female voles. Which of the following graphs predicts the energy allocation that would be favored by selection?

Genetic drift can lead to descendent lineages retaining different subsets of the alleles present in the most recent common ancestor.

Lineage sorting can result in gene trees that conflict with species trees because:

F = 0.80, so the population experiences a lot of inbreeding First, you have to find the expected frequency of heterozygotes (AB) in the population, which is 2pq, p= 0.40 + (0.5)(0.10) = 0.45 q = 1 - 0.45 = 0.55 2pq = 2(0.45)(0.55) = 0.495 Now that you have both the observed and expected frequencies for the heterozygotes in the population (AB), we use calculation for finding the breeding coefficient (F), F = 1 - (obs./exp.) --> 1 - (0.10/0.495) = 0.8 F = 0.8 Since F is large, we expect a high frequency of inbreeding within this population.

Little brown bats can fly, but for some reason they tend to mate in the same cave as their parents and hence have a higher likelihood of inbreeding compared to species that have greater dispersal distances. A researcher found that at one particular locus there were two alleles (A and B), and that the genotype frequencies were as follows: f(AA) = 0.40 f(AB) = 0.10 f(BB) = 0.50 Calculate the inbreeding coefficient, F, for little brown bats. What do you conclude about the frequency of inbreeding in the population? hint: start by asking what information you are looking for, then find the equation and variables that let you do that.

Females positively respond to the song of male 3 > response to the song of male 1 > response to the song of male 2

Male song sparrows (Melospiza melodia) exhibit variation in the quality of their songs. A scientist hypothesizes that song quality is under sexual selection such that female song sparrows prefer to mate with males that sing high quality songs. To test this hypothesis the scientist plays 4-minute song recordings of three male song sparrows to females. Male 1 sings moderate quality songs, Male 2 sings the low quality songs, and Male 3 sings high quality songs. Which of the following findings would most strongly support the scientist's hypothesis?

- increase - decrease - stay the same - stay the same

Many species of monkeyflowers (genus Mimulus) are able to self pollinate, which is the strongest form of inbreeding. In a population of individuals that primarily self-pollinate, one would expect the frequency of homozygotes (AA and aa) to __________, and heterozygotes (Aa) to ________ over time. One would expect the frequency of the A-allele to __________, and the a-allele to _______

Homogenization should occur and the two populations should have similar average depths of the root system.

There are two populations of the same species of tree. - Population 1 occurs along a river where water is plentiful and limited selection occurs for shallow root systems. - Population 2 occurs further away from the river where limited selection occurs for deep root systems. With very high levels of migration, what would you expect root depth to look like in each of the two populations?

- Out of Africa - Multiregional

Under the _____ hypothesis both Homo erectus and Homo sapiens evolved in Africa and then migrated throughout different parts of the Old World independently of each other, whereas under the ______ hypothesis only Homo erectus migrated out Africa and then Homo sapiens evolved from Homo erectus in different parts of the Old World.

- A: 1 - B: 3

Using the character matrix and inferred tree below, answer the following 2 questions: A) Which character provides a synapomorphy for the clade consisting of charmander and vulpix? B) Which character(s) are homoplasious (i.e., show convergence and/or reversals) on the tree?

3 species

Using the character matrix below and the Phylogenetic Species Concept, how many species are identified?

- Variation can occur in the genome and selection can act on this variation - Expression of a genotype - A genotype which can store information

What are the defining characteristics of life we used in class? Pick all that apply

- Differential extinction of the alleles in the ancestral species in the extant descendant species - Polymorphism in the most recent common ancestral species to the extant species in question

What are the two components needed for lineage sorting to occur? Select the two best answers.

A forest found in the middle of two fields is logged and now no longer exists. Individuals from two separate populations of deer found on each of the two fields now travel back and forth between each population, but only breed in their native population range.

What is NOT an example of gene flow?

Principle of Faunal Succession

What piece of evidence allows us to reject Hypothesis 2 (no change but extinction occurs) and supports Hypothesis 3 (extinction occurs and lineages change over time).

An individual's traits can evolve during their lifetime

What was Lamarck's largest misconception about evolution?

Genetic drift

When a population is formed by a very small group of individuals, sometimes alleles that are rare in other populations can become very common or even fixed. For example, Martha's Vineyard was settled by a relatively small group of people, some of whom carried an allele for deafness. Several generations later, deafness was much more common, with 25% of the population being deaf. What process creates these "founder effects"?

The alleles that treefrogs and fire-bellied toads have for the cytochrome oxidase gene are more similar to one another than either is to that of tailed frogs.

When comparing the cytochrome oxidase gene between treefrogs, fire-bellied toads, and tailed frogs, it is found that there are only 9 differences between treefrogs and fire-bellied toads, 15 differences between treefrogs and tailed frogs, and 12 differences between fire-bellied toads and tailed frogs. From this information, in a cladistic (parsimony) analysis without assuming a molecular clock we can confidently conclude that:

Closely related species share an evolutionary history.

When using the comparative method, why can't all species be considered independent data points?

Phylogeny 2

Which of the above phylogenies is more parsimonious based on the characters diet, size, and ears?

Pangenesis

Which of the answer choices best describes this scenario: Elephants in Amboseli National Park had their tusks sawed off by rangers to discourage poaching. The next year, none of the baby elephants had tusks.

Knucklewalking was likely present in the most recent common ancestor of the African great apes. There was a later apomorphy from knucklewalking to walking on the rear limbs in the human lineage.

Which of the following best describes the trait knucklewalking in the apes?

A computer program that has an unchangeable code.

Which of the following examples is NOT alive based on the definition given in lecture?

Independent Assortment generates variation

Which of the following is NOT a tenet of Darwinism as presented in the Origin of Species?

Natural selection is the only means that leads to modification within populations

Which of the following is NOT included in the modern synthesis?

Buttercup, rose, carrot

Which of the following is a paraphyletic group based on the phylogeny?

Female gray treefrogs choose males with long call durations because it is associated with increased foraging capabilities.

Which of the following is an example of female choice?

A female komodo dragon becomes permanently separated from its original population. This Komodo Dragon undergoes obligate parthenogenesis to reproduce and the new population increases up to 20 within 5 years of being separated. parthenogenesis = asexual reproduction in which the offspring develop from unfertilized gametes (eggs in this case).

Which of the following situations would you expect to produce the largest inbreeding coefficient?

Novel traits can arise in a population via mutation, which selection can then act upon.

Which of the following statements about evolution by natural selection is TRUE?

The most parsimonious phylogeny has the fewest number of character state changes, thereby minimizing the number of hypothesized reversals and/or convergences.

Which of the following statements about parsimony is TRUE?

Sexually reproducing species that have overlapping geographic distributions

Which of the following would you most likely be able to effectively apply the biological species concept to?

Phylogeny B

Which of the phylogenies above shows stronger evidence for coevolution between the parasite and host lineages?

C

Which of the trees below shows different relationships than tree A?

The parents are saving and investing energy for future reproductive events

Which of these hypotheses have been put forth to explain why birds do not produce theoretically optimal clutch sizes as predicted by Lack?

All bird species are characterized by the presence of feathers. This character state is genetically-encoded and independent of other characters. Therefore, the presence of feathers is an appropriate character to include in an analysis of bird species.

Which scenario does not include an appropriate character for a phylogenetic analysis?

The common jackal lives in the deserts of Africa but not in the deserts of N. America

Which statement below best provides support for Buffon's Law?

Sexual selection can act differently on males than it does on females

Why is sexual dimorphism (such as a male peacock's brightly colored tail) seen in many species?

5 million years old Species 2 & 3 have 4 differences Species 1 & 2 have 1 difference MRCA of 2 and 3 = 10mya 10/4 = 2.5

You are given the nucleotide sequences shown below. Based on its combination of synapomorphies and symplesiomorphies, a 10 million-year-old fossil appears to be an ancestor of species 2 and 3. Using a molecular clock, what is the inferred age of the most recent common ancestor of species 1 and 2?

No, there is an excess of heterozygotes in the population than expected based on HWE.

You are studying a population of 152 montane shrews in Colorado. You discover that coat coloration in completely controlled by one gene. At this particular gene, the W allele exhibits complete dominance over the w allele. Given the information below, is this population in Hardy-Weinberg equilibrium? f(WW) = black = 0.23 Counts for ww = 31 shrews

Neutral due to the fact that most mutations are neutral or nearly neutral

You are studying a population of Common Goldfish and discover a mutation in a specific sequence of DNA from both the living individuals and preserved museum specimens from the population. What is the effect on fitness likely to be and why?

The difference in their environment led to the change in the phenotype between the two groups.

You have 30 water fleas and they are all clones of one another. You raise half of them with predators in their tank and half of them in a tank without predators. After they fully develop, you take pictures of the water fleas and you notice that the group that developed with predators have what look like helmets (right in photo below) whereas the other group just have normal smooth heads (left in photo below). What's the best explanation for this?

4 million years old

You have the following nucleotide sequences shown below of 3 species of plants. The most recent common ancestor of the shrubs and of the climbers are 2 million-years-old. Using the molecular clock, what is the age of the most recent common ancestor of the shrubs, climbers, and creepers?

No; the expected frequencies do not match the observed frequencies.

You observe a population of northern flickers (a bird in the woodpecker family, common in Fort Collins) in your backyard. They all have patches of color at the corner of their beaks - some of the birds have a black patch, while others have a red patch. When you look into the literature about northern flickers, you find that the black patches are produced by the genotypes BB and Bb, while the red patches are produced by the genotype bb. You capture 20 birds and sequence their DNA to determine the following observed numbers: 3 birds with BB 12 birds with Bb 5 birds with bb. Are these birds in Hardy Weinberg Equilibrium for patch color?

f(AA) = 0.13, f(Aa) = 0.46, f(aa)= 0.41

You observe a population with allele frequencies at a particular locus of f(A) = p = 0.36, f(a) = q = 0.64. What are the expected genotype frequencies if the population is in Hardy-Weinberg equilibrium (rounded to two decimal places)?

Catastrophism

The Chicxulub meteorite impact resulted in massive planet-wide extinctions, but also deposited a layer of rare-element clay across the planet within months. This layer is visible in the geologic record.

D

The best-supported phylogeny of the great apes is:

Both parties are harmed

spite

Males attempt to deceive females; females attempt to deter the males' deception.

An evolutionary "arms race" between the sexes can occur within a given species because:

Cladogram A is more consistent with the prosecution's charge than is cladogram B.

A drug-using defendant in a court case is charged by the prosecution with deliberately infecting other IV (intravenous; needle-using) drug users with his West Nile Virus. Which of the following cladograms of virus strains isolated from the defendant, an alleged victim, and other members of the community who are not drug users, but are infected with the West Nile Virus, would be more consistent with the prosecution's charge?

Use of multiple alternative hypotheses

An important component of Strong Inference is:

Because giraffes and pangolins are distantly related to each other, their alleles are analogous to each other.

A friend of yours is researching DNA sequences in all mammals. Your friend discovers that a pangolin species has the same allele in a gene as a giraffe species. That allele is unique to those two species and not seen in any other mammals. Giraffes are part of the Artiodactyla order while pangolins are part of the Pholidota order, as seen in the image below. Giraffees are highly supported as members of Artiodactyla based on both morphological and other genotypic data. Likewise, pangolins are highly supported as members of the Pholidota order based on both morphological and other genotypic data. Based on this information, what is the best explanation for why the giraffe and pangolin species share the same allele?

Mice reproduce sexually

A group of researchers are studying the Mc1r gene, a gene associated with melanin deposition, in a population of mice. They test for Hardy-Weinberg equilibrium (HWE) and find that this population is in disequilibrium at this particular gene. In other words, the observed genotype frequencies do not match the expected genotype frequencies at the Mc1r gene. Which of the following could NOT be an explanation for disequilibrium (lack of HWE)?

System of mating approach that uses observed and expected heterozygote frequencies

A group of researchers is interested in determining the level of inbreeding in a population of 120 tortoises. Which of the following methods would be most appropriate for these researchers to use?

Yes, because E and F represent a monophyletic group nested within the paraphyletic group of D, G, and H

A member of the janitorial staff developed a terrible bacterial infection that caused him to miss many days of work (without pay!). He believes that a laboratory latex glove that he picked up on the floor of a microbiology lab while on the job might be the culprit. Hoping to get compensation from his employer, the janitor asks for the help of a microbiology researcher to determine if he has a case against his employer. The researcher determines that the janitor possesses bacterial strains represented by E and Fin his bloodstream. The glove (which thankfully he saved!) possessed strains represented by D, G, and H. Does the janitor have a case against his employer? (Essentially, is there evidence to suggest directionality from the glove to the janitor?)

Both Relative and Radiometric dating

A paleontologist was working at a dig site in Southeast Africa and discovered the fossil of an unknown mammal 10 meters deep in the soil. The next day, while digging deeper, she finds the fossil of an unknown reptile. Upon further analyzing isotope data, she determines that the mammal fossil is 300 million years old whereas the reptile fossil is 450 million years old. What process(es) allowed for her to determine that the reptile fossil was older than the mammalian fossil?

- directional - reduce

A population of Island Scrub-Jays live on Santa Cruz Island, off the coast of southern California. This year has been a particularly dry with minimal rainfall and limited seed production for the spring. The smaller-sized jays are able to consume enough food and reproduce, whereas the larger jays with higher biomass are unable to collect enough nutrition to mate this year. Body size has been shown to be heritable in this population. This type of _____ selection will _______ the variation in the population.

- Environmental effects - Multiple alleles

A population of diploid (2n) cutthroat trout exhibits a lot of variation in size. A study shows that trout length is affected by one gene with following alleles: L1, L2, L3, L4, L5, L6, L7, L8, L9, as well as by the temperature of the water. Based on this information alone, which of the following mechanisms could be contributing to the continuous variation in trout size? Select all that apply.

There is not enough information to determine if this will evolve by natural selection

A population of flying squirrels has the ability to glide from tree to tree. A recent fire destroyed about 50% of the trees used by flying squirrels in this region. Some squirrels have larger patagia (see below) that allow them to glide for longer distances. In this generation, the squirrels with larger patagia are able to defend a larger territory and reproduce more resulting in a higher relative fitness compared to squirrels with smaller patagia. With respect to the size of the patagia, is this population likely to evolve by natural selection? [HINT: Consider all of the postulates of natural selection.]

She can reject the rate of living theory because some mosquitoes evolved longer lifespans.

A population of mosquitoes has females that can lay up to 100 eggs per clutch and can have up to 3 clutches in their lifetime (~50 days). Males fertilize multiple clutches of eggs in a single night and have a life span of ~10 days. There is variation in lifespan in both males and females with longer-lived individuals having lower metabolic rates. A scientist tested one of the hypotheses underlying the rate-of-living theory of aging in this population. Here was her experimental design: She interbred offspring from the 3-clutch females for 20 generations to generate a long-lived line. She interbred offspring from the 1-clutch-only females for 20 generations to generate a short-lived line. After the 20th generation she compared the lifespans. Here were her results: Females from the long-lived line had significantly longer life spans from the short-lived line females. However, there was no significant difference in males between the two lines. What can the scientist conclude from her experiment?

16.0mm h^2 = 0.4 R = ? S = Zparents - Zpopulation = 100mm - 60mm = 40mm h^2 = R/S R = h^2 x S = 0.4 x 40mm = 16mm

A population of parrot fish has a heritability value of 0.4 for body length. If the mean phenotypic value for tail length is 60mm, but you select a subpopulation with a mean value of 100mm to breed in the next generation, what will be the response to selection?

- 2 - 3

A researcher is interested in the evolution of body size among the 5 related species of frog shown above. Phylogenetic trees A and B are identical to each other with respect to showing relationships among the five extant species. They only differ in whether small (phylogeny A) or large (phylogeny B) body sizes are inferred to be present in the most recent common ancestor of the five extant species. Based on parsimony, what are the least number of changes that can occur to describe how body size evolved for phylogenies A and B? NOTE: make sure to consider the state (small or large body size) that has been assigned to the most recent common ancestor of these 5 species. PHYLOGENY A: ________ PHYLOGENY B: ________

No, it can only be observed between two or more unlinked genes (such as on different chromosomes).

A scientist is conducting a monohybrid cross to examine the laws of inheritance in a butterfly. They are examining the trait of brown or black wing spots, which is controlled by a single gene. The scientist crosses Parentals (a BB black spot with a bb brown spot), then crosses two Bb F1 offspring and evaluates the results in the F2 offspring. Can they observe the Law of Independent Assortment in action with this cross? Why/Why not?

Island 1 will have higher genetic variation than island 2

A species of lizard exists on the mainland and occasionally migrates to islands offshore. The islands are approximately the same size as each other (can support the same size population) but are smaller than the mainland. Given what you know about migration, how do you expect the genetic diversity to compare between the two islands?

No, because the Biological Species Concept requires evidence of reproductive isolation

According to the Morphospecies and Phylogenetic Species Concepts, Baymax and Wall-E are members of two different species. Does this mean that they must also be recognized as members of two different species according to the Biological Species Concept?

True

Across species A-E, we can infer that presence of enlarged eyes is not an adaptation to a subterranean lifestyle.

Runaway sexual selection

African long-tailed widowbirds are sexually dimorphic. The males have very long tail feathers, even though those feathers may hinder their ability to fly. Research has shown that females preferentially mate with males that have long tail feathers. Which hypothesis below could be supported by these observations?

Although this trait has no genetic basis, it persists due to causing increases in their individual fitness.

All of the following are reasons infanticide would be favored by natural selection except:

RNA strands are less stable than DNA strands

All of the following provide evidence that RNA most likely originated before both DNA and proteins, EXCEPT:

- dispersal - vicariance

Allopatric speciation occurred to a species (species A) that live on a big island illustrated below. Over time (progressing from left to right on the map), a new, smaller island is formed very closel to the big island where species A lives. Some adventurous individuals decided to swim to the new island. This newer island gradually grows bigger as time goes by and is pushed further away from the big island. A huge earthquake then occurs on the big island and the island is split in half. The individuals living on the big island can no longer travel from one side of the island to the other as the split has grown larger and the distance is too far for the individuals to swim. Over time, the populations on the left side of the island become species C, the populations on the right side of the island becomes species D, and the populations on the small island becomes species B, as these populations diverge from each other because of novel mutations and lack of gene flow. The panthers swimming to the little island is an example of __________ while the earthquake occurrence and the separation of the panther species is an example of _________.

The actor is harmed and the recipient benefits

Altruism

- sperm competition - male-male combat

Among apes, chimpanzees and bonobos have large testes relative to their body size. Males with larger testes produce more sperm and have an increased chance of fertilizing an egg after mating with females. In contrast, gorillas have small testes relative to their body size, but there is more pronounced sexual dimorphism among gorillas. Male gorillas exhibit variation in body size, and larger males are more successful at acquiring mates. Based on this information, chimpazees and bonobos likely rely on ________ to increase fitness, whereas gorillas likely rely on _______ to increase fitness.

High frequency

An island is recently inhabited by its first vertebrate species: a skink (lizard). There are no predators on this island for the skinks, and there is endless food and resources: a perfect environment. A mutation arises in the population of skinks that leads to a slight reduction in the number of eggs a female lays (14 eggs instead of 15 eggs). This mutation is fairly common (it's a point mutation in a region of the genome with a high mutation rate). Over time, what would you expect the relative frequency of this gene to be?

0.3021 pt = 0.7 using this info, we can find qt 1-p=q qt=1-0.7 = 0.3µ = 0.003 changing A->a It is asking for the f(a) after 1 generations, or qt+1. We know that the mutations are reducing the frequency of A and increasing the frequency of a. Therefore: qt+1 = qt +qtµ = 0.3 + (0.7)(0.003) = 0.3 + 0.0021 = 0.3021 or pt+1 = pt -ptµ = 0.7 - 0.0021 = 0.6979 qt+1 = 1- pt+1 = 1-0.6979 = 0.3021

At time t, the frequency of the dominant A allele in a population is 0.7. The mutation rate changing this dominant allele to the recessive allele at this locus is 0.003. If mutation alone is affecting allele frequencies in this population, what would the allele frequency for the a allele be after one generation (t+1)?

- G - D - I - H - B - A - E

Based on the character matrix below, mark all characters that are parsimony informative (where the numbers in the table represent different character states).

Homology

Based on the information given in the following phylogeny, loss of legs in both snakes and legless lizards is an example of all of the following EXCEPT:

- Trout, Bass, Rockfish, Herring, Cap, Catfish - Salmon, Sturgeon - Bass, Rockfish - Herring, Cap, Catfish - Cod, Sturgeon, Salmon - Cap, Catfish

Based on the phylogenetic tree, mark all monophyletic groups.

- Paraphyletic - Monophyletic

Based on the phylogeny shown above, fill in the following blanks. A group consisting of only turtles, lizards, snakes, and crocodiles ("herpetofauna") is an example of a _______ group. A group consisting of only crocodiles, birds, lizards, and snakes is an example of a _________ group.

The phylogeny in the context of the geological history provides evidence for dispersal.

Based on the phylogeny shown together with the geological history and map of the Hawaiian Islands, which of the following statements can we infer? Each letter (A - R) in the phylogeny indicates a different species.

Phylogeny II is most well-supported tree based on the characters sampled in this study.

Below are three hypothesized phylogenies to explain the relationship among some pine species. Researchers applied the bootstrap method to determine the support for each phylogeny. They found that 90% bootstrap support for Phylogeny II, 8% bootstrap support for Phylogeny I, and 2% bootstrap support for Phylogeny III. What can the researchers confidently conclude based on these results?

- symplesiomorphy - reversal

Below are two tree hypotheses for the evolutionary history of a character. In Tree 1, the character state shared by species 1 and 4 is an example of a _______. In Tree 2, the character state in species 4 is an example of a ________

- Natural Selection - Mutation

Biometricians argues that _________ is the primary mechanism of evolution and whereas Mendelians argued that ________ is the primary mechanism of evolution.

Likely evolved by direct selection rather than by kin selection.

Black-Tailed Prairie Dogs are also known to give warning calls in the presence of mammal predators. However, in this species, individuals call at the same rate when surrounded by family as they do when surrounded by unrelated individuals. Moreover, individuals who call tend to get eaten less frequently. This suggests that calling behavior in this species:

0.125

Calculate the relatedness (r) between diploid individuals A and B. Squares = males; Circles = females

Vestigial eyes could be exhibiting homoplasy because of convergence

Cave salamanders (Proteus anguinus) and northern cavefish (Amblyopsis spelaea) both live in dark caves and have reduced/vestigial eyes. Most other salamander species have [functioning] eyes, as do most other fish that are closely related to the cavefish. Based on this distribution of species that have functioning and reduced/vestigial eyes, what can we infer about the evolution of reduced/vestigial eyes?

Microevolution is concerned with the processes that lead to changes in allele frequencies within a population. This may lead to speciation and thus differences among species at the macroevolution level.

Choose the answer that best describes the relationship between microevolution and macroevolution.

- D: Attack - B: Retreat - C: Retreat - A: Retreat - E: Attack

Consider the experiment to test the function of the wing markings and wing-waving display in tephritid flies (Zonosemata). If our hypothesis is that only the wing-waving display, but not the markings, deter jumping spiders, what behavior would we expect to see in jumping spiders that encounter flies with each of the following treatments: - D. Housefly with Zonosemata wings. - B. Zonosemata with own wings cut and reglued. - C. Zonosemata with housefly wings. - A. Zonosemata untreated. - E. Housefly untreated.

Yes, because both ancestral polymorphism and differential extinction is demonstrated.

Consider the following gene tree. Is this an example of lineage sorting?

Non-synonymous Nonsense mutation

Consider the following two sequences: Original: CUU CCC AAA GGG UGG ... Mutated: CUU CCC AAA GGG UGA ... This is an example of what kind of mutation? You may use this genetic code to help you answer the question.

1

Consider the graph below. Which slope represents the trait with more variation controlled by genes?

Uniformitarianism

Evidence suggests the Grand Canyon formed million of years ago, and has been gradually shaped due to forces such as erosion to this day.

Gradualism

Fossil evidence shows that species in the horse lineage have increased in size from about the size of a dog to the size of modern horses over the course of about 50 million years.

Genetic linkage

Gene 1 encodes for claw length (short; long) and body size (big; small) while gene 2 encodes for dorsal coloration (brown; white). These genes are adjacent to each other on chromosome 3 in the focal species. This species lives in the Arctic, and selection favors white individuals because they can escape predation through camouflage. Selection also favors large body sizes, which have an increased capacity for thermoregulation. A population is sampled and most individuals are in that population are found to be white and small. What could best explain these observations about color and size?

All of these can influence evolution by genetic drift.

Genetic drift is completely random, although some factors can affect the outcome. Which of the factors listed below could contribute to the evolutionary impact genetic drift has on a population?

Sexual selection is stronger in females than in males. Males should be more choosy, and females should be more competitive

Given the graphs below, what can you predict about sexual selection in this population?

f(black) = 0.615, f(orange) = 0.385

Halloween is coming up, and you decide to buy a bag of orange and black candies. You've never had this candy before, so you decide to eat some pieces for quality control purposes. You take out two pieces at a time and note whether the combination you eat is black-black, black-orange, or orange-orange. Before you know it, you finish the entire bag of candy! You counted 39 black-black, 45 black-orange, 16 orange-orange. What are the frequencies of the two colors? Hint: The individual colors are analogous to alleles and the combinations are analogous to genotypes

Flash flood avoidance is a preadaptation in Abedus herberti because it increases fitness, but evolved in their ancestors in response to a different selective pressure.

Heavy rainfall can result in flash floods that kill up to 90% of aquatic insects. During heavy rainfall the giant water bug Abedus herberti travels away from streams. This behavior reduces the mortality caused by flash floods of Abedus herberti to 15%. An examination of species closely related and ancestral to Abedus herbertithat inhabit regions without flash floods reveals that they use heavy rainfall as a signal to move temporarily out of the river to search for food. Which of the following statements is most strongly supported by these observations?

- Ribozymes have a phenotype without the use of proteins. - Ribozymes simultaneously have a genotype and a phenotype.

How do ribozymes support the hypothesis that RNA came before DNA or proteins? Select all that apply.

- not evolving - the same

If observed allele frequencies are equal to expected allele frequencies, then the population is in Hardy-Weinberg equilibrium, and is therefore ________. Under the assumptions of Hardy-Weinberg, in 20 generations, the allele frequencies will be ________.

4

Imagine a New York City rodent population in which a 5-year-old female rat can rear 6 offspring in a breeding season without any help. If she receives help from her 3-year-old sister, she can rear a total of 15 offspring in a breeding season. What is the maximum number of offspring that the sister can give up for this altruistic behavior to be favored? Assume these are full-sibs and diploid; only consider this single generation.

- 0.75 - 20 - 20 - No - Because B < C/r

In a haplodiploid population of wasps, a female individual can either help her sister rear offspring, or set off to rear her own offspring. If she helps her sister, she rears no offspring of her own, but her sister can rear 40. If she sets out on her own, she can rear 20 offspring of her own, but her sister only rears 20. Calculate the following values from Hamilton's rule. Relatedness of the haplodiploid sisters, r = _________. Benefit to the recipient, b = _______ Cost to the actor, c = _______. According to Hamilton's rule, would we expect the allele for helping to increase in frequency? ______ Why? ________

Genetic drift due to a bottleneck could cause the litter size to become fixed at 2 bunnies per litter by chance alone.

In a rabbit population, individuals vary in how many bunnies they have per litter - ranging from 2 to 10 with an average of 5. The optimal litter size is 7 bunnies (according to Lack's Hypothesis). Domestic cats move into the area one year and the rabbit population experiences a drastic reduction in population size. What pattern of evolutionary change in the life-history trait of litter size might we expect in this scenario?

False

In a system in which females are the choosier sex, sexual selection acts only on the male traits that the females use to choose between males.

The rate of increase for allele "A" would occur faster in population 2

In population 1, selection favors the dominant allele "A" with the following relative fitnesses for each genotype: AA=1; Aa=1; aa=0.5 In population 2, selection factors the dominant allele "A" with the following relative fitnesses for each genotype: AA=1; Aa=1; aa=0.3 How would the rate of change in allele frequencies differ in population 2 compared to population 1?

Selfishness

In spadefoot toads, when occupying densely populated ponds, some individuals may develop cannibalistic morphologies (e.g., enlarged keratinized oral sheath). Cannibalistic individuals have been shown to preferentially prey on tadpoles that are more unrelated to them (i.e., eat cousins over siblings). What would you hypothesize this to be an example of?

4

In the table below there are 6 populations of individuals and you have information on the alleles present at three genes from each individual in those populations. Based on the phylogenetic species concept as presented in class, how many species are there based on this information?

Extinction

Irish elk fossils occur across Europe and Britain. Anatomical analysis shows that these fossils are not elk, moose, reindeer, or any other extant ungulate. Irish elk fossils provide evidence that best supports what aspect of evolutionary change evolution?

Yes, because the gene tree shows that allele A and B are more closely related than either are to alleles C or D. By contrast the species that has allele B is more closely related to the species that has allele C.

Is there a conflict between the gene tree (in red) and the species tree (in black) below?

Antagonistic Pleiotropy Hypothesis

Mutation at a gene responsible for growth results in strong competitive ability, which increases mating success. However, individuals with this mutation also have an increased susceptibility to disease later in life and, consequently, early senescence. This provides evidence for which of the following hypotheses?

It generates genetic variation on which selection can act.

Mutation is an important evolutionary process because:

Both parties benefit

Mutualism

- common descent - vestigial traits

Olms, a kind of cave-dwelling salamander, have skin-covered eye-spots, that do not aid in sight. Closely related salamanders have functional eyes. Select the two answers that best fill in the blanks for the statements below: This is an example of [____], thus providing evidence of [____].

Allopatric speciation via vicariance

One tailed frog species used to inhabit the entire western half of the northern USA prior to the formation of the Rocky Mountains. With the uprising of the Rocky Mountains, populations from the eastern side of the mountains became isolated from populations on the western side. Over ~5 million years, these frogs evolved without gene flow across the Rocky Mountains, and they are now considered two separate species. What kind of speciation event occurred?

Religious beliefs exist on a continuum with Evolution. They are not mutually exclusive.

Please select the answer that best describes the relationship between Evolution and Religious beliefs.

The effect of the mutation depends on the environment.

Rabbits are normally brown, but there is a mutation that can make some rabbits white. It is observed that brown rabbits are preyed upon less - so they have higher survival - for most of the year. But when snow is on the ground during the winter months, the white rabbits are preyed upon less and their survival is higher than the more common brown rabbits. The observer notices this cycle every year. This observation illustrates that...

No, because the phylogenetic relationship among species has not been accounted for in their graph (i.e., the species may not be independent points)

Researchers are interested in the relationship between wing size and and windy habitats in species of damselflies. They hypothesize that larger wing sizes enable individuals to fly in windy environments where smaller wings would not. The authors collect data on six different species of damselflies and find the results below. Based on these results, can the authors conclude that wing size is an adaptation to windy environments?

D

Researchers hypothesize that species of aphids coevolved with the species of plants they inhabit. Below are hypothetical trees showing the plant tree (i.e., the plant phylogeny) on the left, the aphid tree on the right, and a dotted line indicating which species of aphid occupy which species of plants. Based on these trees, which node does not support the coevolution hypothesis. Select all that apply.

- The additional data provided increased support for the close relationship between Species G and Species H - The additional data provided increased support for the close relationship between Species E and Species F - The additional data provided increased support for the close relationship between the monophyletic group of Species A and B and the monophyletic group of C and D.

Researchers used four characters to construct the phylogenetic tree in Analysis 1 that is shown below. Realizing that many of their clades had low bootstrap support, the researchers re-ran the analysis after collecting more data on the same species as in Analysis 1. The results from this second analysis are shown in Analysis 2. Based on this information, which of the following statements is/are TRUE (select all that apply)?

Shave polar bears and re-attach their own fur back on

Researchers wish to conduct an experiment to test for an adaptive function of a polar bear's fur. They want to compare the fitness of polar bears possessing naturally white fur with fur coloration of grizzly bears that have adapted to live in warmer environments. To make this comparison, they capture a number of polar bears so that they can manipulate their fur. For their treatment group, they shave the polar bears and attach a coat of grizzly bear fur. An appropriate control for this treatment would be to:

The scientists reject the hypothesis that sugar has no effect on singing rate in zebra finches.

Scientists are studying the effect of sugar on singing behavior in male zebra finches. They find a significant difference in singing rate between birds that receive a high sugar diet versus birds that receive a low sugar diet. Which of the following is a valid conclusion from this study?

The most recent common ancestor of all extant organisms was not necessarily the first life form.

Select the most accurate statement about the most recent common ancestor of extant organisms.

The actor benefits and the recipient is harmed

Selfishness

0.39 The 7% refers to f(ss). F(ss)= 0.07=q^2 q= sqrt(0.07)=0.265 Rearrange equation: p+q=1 p=1-q=1-0.265=0.735 We now have the values for p and q and can solve for f(Ss) F(Ss)=2pq=2*(0.735)*(0.265)=0.39

Sickle cell anemia occurs in individuals with a homozygous recessive genotype in the sickle cell locus (ss). The sickling of the red blood cells can cause severe illness, but also prevents infection by the malaria parasite. Homozygous dominant individuals (SS) have normal red blood cells, but are susceptible to malaria. Heterozygous individuals (Ss) can have more mild sickling of the red blood cells, but still maintain some resistance to malaria. In order to predict malaria dynamics, we would like to estimate the proportion of the population that is heterozygous. If we know that 7% of the population has sickle cell anemia and we assume the population is in Hardy-Weinberg equilibrium, what proportion of the population is heterozygous?

Homologous structures

Some scientists believe that the rock hyrax (Procavia capensis) is one of the closest living evolutionary relatives to the elephant! Some evidence for this includes the fact that they share many reproductive characteristics, including testes that remain in the retroperitoneal abdomen, mammary glands located closer to the front legs, and relatively long gestation periods. Additionally, the incisors of hyraxes are more similar to elephant tusks than to rodent teeth. If hyraxes are indeed a close relative to the elephant, then these characters would be examples of _______________.

The atmosphere of early Earth when life arose is no longer believed to have been primarily of composed ammonia and methane

Stanley Miller's 1953 experiment produced organic compounds capable of forming the building blocks of DNA from an approximation of early Earth using methane, ammonia, water, and an energy source. Why must these impressive results be interpreted with caution?

Population B is larger

The plot above shows how the frequency of an allele changes over time in two populations. If we assume that drift is the only force acting in these populations, what is the most likely scenario that could produce these patterns?

False

The primordial life form is the same as LUCA (the last universal common ancestor of extant life)

The female is choosy because she has a larger parental investment.

The reproductive behaviors of the common Suriname toads (Pipa pipa) are unusual. During amplexus (i.e., frog mating), female toads will release eggs for external fertilization, which males toads will fertilize. Males will then perform swimming maneuvers until the eggs become embedded onto the females' backs. The mother will then carry the fertilized eggs on her back, protecting her clutch from predators and ensuring that they receive sufficient oxygen, until the eggs hatch. Based on this information and the lecture material, which sex would be expected to be choosy and why?

The models that resembled yellow-eyed Ensatina had significantly fewer attack marks than the other models.

The salamander Ensatina eschscholtzii xanthoptica (yellow-eyed Ensatina) has a color pattern that very closely resembles a brightly colored poisonous newt that co-occurs in the same habitat. A scientist hypothesizes that this color pattern is an adaptation (because predators will avoid the salamander if it looks poisonous) and performs the following experiment to test his hypothesis: 25 clay models of salamanders are painted to mimic the yellow-eyed Ensatina. Another 25 were painted to mimic a drab-colored salamander. These models are then placed within the range of the yellow-eyed Ensatina and left for 25 days. The clay models are then collected and the number of attack marks recorded. Which of the following results would provide evidence that supports the scientist's hypothesis?

0.25 Relative fitness = # offspring individual produces / maximum offspring produced = 3/12 =0.25

There are four male elephant seals in this population and the number of offspring that each male has is provided below. Based on this information, what is the relative fitness of Seal 3? Seal 1: 7 offspring Seal 2: 5 offspring Seal 3: 3 offspring Seal 4: 12 offspring

Sympatric speciation

There are many populations of blackbirds that together form a contiguous (that is, uninterrupted) geographic range. A mutation arises in a population of blackbirds such that the mutated individuals produce a blue band rather than a red band on their wings. Through strong assortative mating, over time this population of blue-band blackbirds diverges and becomes a new species. This is an example of:

Frog species B

There are two frog species (A and B) living in a pristine, montane environment. Thirty individuals of each species are captured and moved to a polluted, urban stream. The mutation rate in functional genes of Species A is 7 * 10^(-8). The mutation rate in functional genes of Species B is 3*10^(-5). They both have the same number of functional genes. The species that is more likely have a beneficial allele arise and adapt to the new environment is

The population that is farther from Wyoming as there is no migration and strong genetic drift.

There are two populations of Boreal Toads in northern Colorado. Both are very small in size and undergo strong genetic drift. One population has been relocated further north and some individuals from a much larger population in Wyoming are now migrating to that population. Which population do you expect to have more fixed alleles after 50 generations?

The Oak Population does not violate any assumptions of Hardy-Weinberg principles while the Pine Population does

There are two populations of Island Scrub Jays - one that lives in oak habitat and one that lives in pine habitat. A researcher is studying a gene that she thinks may be under selection for beak shape. She runs Hardy-Weinberg analyses and reports the results below. Why could the populations show different results for the same gene?

11.5 Use equation = h^2 = R/S = (Zoffspring - Zpopulation) / (Zparents - Zpopulation) h^2 = 0.75 R = Zoffspring - Zpopulation = Zoffspring - 16mm S = Zparents - Zpopulation = 10mm - 16mm = -6mm h^2 = R/S = (Zoffspring - Zpopulation) / (Zparents - Zpopulation) 0.75 = (Zoffspring - 16mm) / -6mm -4.5mm = Zoffspring - 16mm 11.5mm = Zoffspring

You've been working in a fish husbandry lab, and you notice that some of the fish have a much larger dorsal fin than others. The mean dorsal fin size in this population is 16 mm. Previous research found the heritability for this trait to be 0.75 based on a midparent-offspring regression. What is the mean dorsal fin size of the offspring if the mean dorsal fin size of the breeders is 10 mm?

They fail to reject the null hypothesis that there is no relationship between the number of worms on the hook and the number of bites they get.

Your fishing partner is interested in determining whether increasing the number of worms on their hook influences the number of bites they get. They find no significant difference in the number of bites they get when they have one worm versus when they multiple worms. What can your fishing partner conclude about the relationship between the number of worms and the number of bites they get?

- An amniotic egg - a lack of four limbs

_________ is an example of a synapomorphy for just primates, rodents and rabbits, crocodiles, and birds and ______ is an example of a symplesiomorphy for just sharks and ray-finned fish.