Evolution Questions and Answers

Choose all of the following situations below that are examples of pre-zygotic barriers to reproduction. (Choose all that apply) a. The embryo dies due to a lethal combination of genes b. Incompatibility of sperm and eggs (sperm cannot fertilize the egg) c. Behavioral isolation d. Lions and tigers produce hybrid offspring, but all hybrids are sterile e. Two species of ants are capable of breeding under laboratory conditions, but do not because one species is only found in association with white pines and the other ant species is only associated with willows, thus the two ant species never occur together in nature to breed f. Ecological isolation

Red touch yellow, kill a fellow. Red touch black, venom lack. This is a short rhyme that was written to make it easy to tell apart two very similar looking North American snakes, the coral snake and the king snake. The coral snake is very venomous while the king snake is harmless. However, if you don't remember the order of the stripes, it can be very difficult to tell the two snakes apart. This is an example of: a. Evolutionary arms race b. Endosymbiosis c. Batesian mimicry. d. Müllerian mimicry e. Mutualism

A population of Daphnia in a crystal clear lake (Lake A) has genetic variation that increases melanin production and helps with the very high UV light exposure at this particular lake. But when members of this Daphnia population are transplanted to another lake (Lake B) with similar conditions except UV radiation is much reduced, the Lake A Daphnia are out competed by the Daphnia that are native to Lake B. Which of the following best explains this? a. The UV exposure in the Lake A Daphnia made them less fit. b. This isn't possible because the Lake A Daphnia will always be more fit. c. Evolutionary changes can be advantageous under some environmental conditions but disadvantageous under others d. UV resistant phenotypes always out-compete non-resistant phenotypes e. Evolution always maximizes the improvement or progress of a species

Which of the following is not an assumption of the Hardy-Weinberg theorem? a. There is no migration or gene flow from outside of the population. b. There is no mutation in the population. c. There is no selection in the population. d. The population size is effectively infinite and thus not undergoing genetic drift. e. Mating is non-random.

Several decades ago, research into human evolution and the coalescence theory when applied to human genomes resulted in dubbing a woman who lived long ago "Mitochondrial Eve." What does this mean? Mitochondrial Eve was the first human woman. Each gene in humanity can be traced back to a single gene copy that existed in one of our ancestors. "Mitochondrial Eve" is the woman whose mitochondria was the ancestral mitochondrial copy for all surviving humans today. Each gene in humanity can be traced back to a single gene copy that existed in one of our ancestors. "Mitochondrial Eve" is the woman whose genes were all the ancestral gene copy for all surviving humans today. "Mitochondrial Eve" was the first eukaryotic organism to capture the bacteria that eventually became the mitochondria.

Which of the following events can be the origin of a new gene in a species? (select all that apply) a. The fixation of a new mutation through genetic drift b. A nonsynonymous mutation in an existing gene c. A chromosome mutation that join together exons from different genes d. A synonymous mutation in an existing gene e. The acquisition of a gene from a different species through horizontal gene transfer f. The duplication of an existing gene

Some populations of Tiger Salamander have the ability to not undergo complete metamorphosis. Some individual salamanders will retain tadpole like characteristics like gills throughout their life if they live in water body with good environmental conditions. Despite remaining tadpole-like they develop sexually and can breed. However, if environmental conditions in the water are not favorable, they will undergo metamorphosis and become terrestrial, avoiding bad conditions in the water. The above paragraph includes explicit examples of... (choose all that apply): a. Evolvability b. Heterochrony c. Phenotypic Plasticity d. Canalization e. Disruptive selection f. Paedomorphosis g. Genetic Assimilation h. Purely genetically determined phenotypic variation

If chimpanzees and humans are each other's closest relatives, how do you explain the fact that chimpanzees have an opposable hallux (big toe) like gorillas, but unlike humans? (Pick the most parsimonious answer) a. Gorilla and chimpanzee lineages independently evolved an opposable hallux b. The opposable hallux is an ancestral character that has been modified in the human lineage c. Chimpanzees are more closely related to gorillas than to humans d. In young gorillas and chimpanzees, the hallux becomes opposable as they climb trees, and this trait is passed on to their offspring e. Chimpanzees and gorillas have a developmental constraint that prevents the hallux from resembling the human morphology

The Dobzhansky Muller model provides an explanation for why hybrids have low fitness. Which description below accurately represents this explanation? a. Two populations diverge at a single locus, such that one population is fixed for the ancestral homozygous genotype (AA) while the other population is fixed for a derived genotype (aa). The "Aa" hybrids, however, are low fitness and therefore the populations are reproductively isolated by underdominance at a single locus b. Two populations diverge, such that their hybrids have an unfit combination of alleles at two or more loci. Divergence at these loci does not require underdominance, but rather an epistatic interaction that renders hybrids low fitness c. Two populations converge, such that hybrids have numerous recombinations of alleles at various loci. This results in hybrids with low fitness d. None of these statements correctly describes the Dobzhansky Muller model

Imagine a hypothetical population of 100 individuals that is completely isolated from other populations. This population has two alleles (A and a) at a particular locus and there are are no fitness differences between the AA, Aa, and aa genotypes. Assume no mutation can occur in this population. Given these conditions, what will happen to genetic variation at this locus? a. Increase through genetic drift b. Become lost due to genetic drift c. Become a stable polymorphism d. Be maintained due to the absence of selection e. Become lost due to lack of selection

An individual is heterozygous for a chromosomal inversion that lowers fertility while individuals that are homozygous do not experience lower fertility. Which model of selection best describes fitness variation for this locus? a. incomplete lineage sorting b. overdominance c. stabilizing selection d. directional selection e. heterozygote advantage f. underdominance

There are two species of omnivorous crab in the same genus. When these two crab species occur sympatrically one crab will evolve larger claws that are useful for breaking the shells of small snails, while the other crab tends to evolve smaller and sharper claws that are useful for tearing apart pieces of macroalgae. Despite both crabs being omnivorous, they will eat different food when they co-occur on the same shore. These two crabs are responding to competition by exhibiting: a. Character displacement b. Sympatric speciation c. Ecological release d. Competitive exclusion e. Allopatric speciation

Research looking at the genetic differences in human populations resulted in a calculated Fst value of approximately 0.12. Based on this value, which of the following statements are supported? a. Humans have genomes that are 12% different from each other on average. b. People from different parts of the world have genomes that are 12% identical. c. Only 12% of the genetic variance we see between human individuals is likely to be due to differences on the group level. d. Approximately 12% of the original early Homo sapiens population left Africa. e. The genetic variation between humans within a group tends to be higher than differences between the groups.

Bowhead whales are the only species of large whales that live their entire life in the icy water of the Arctic Ocean. They have a couple adaptations that help them do this. First, bowhead whales have a thick layer of fat under their skin called blubber that helps keep them warm. The blubber of bowhead whales is 18 inches thick, which is thicker than any other whale. Second, bowhead whales have a remarkably thick skull. This allows them to break thick ice in order to get air to breathe. No other whales have such thick skulls. Available evidence shows that bowhead whales evolved from ancestors that lived in the warm waters of the Pacific Ocean and did not have either thick blubber or thick skulls. Which of the following is the best description of the role cold water played in the evolution of thick blubber? a. It forced all the whales to change so they could survive and reproduce. b. It made the whales work to stay warm and these efforts caused whales to change. c. It caused mutations that gave whales thicker and thicker blubber. d. It helped determine which whales each generation survived and which did not. e. It directly influenced the growth and development of the whales.

Organisms become more complex over time, therefore it isn't possible for an organism to reverse this and become more simplified. This applies to both morphology and genome content. True False

In a population the offspring produced tend to be 60% female and 40% male. This bias in sex ratio was investigated and it was found that an allele of a gene in the Y chromosome caused sperm that carried this allele to be less effective at fertilizing eggs. This led to sperm that carried Y chromosomes to be slightly less effective at fertilization compared to sperm cells with the X chromosome, explaining the uneven sex ratio. This is an example of: a. Good genes model b. Meiotic drive c. Reinforcement d. Genetic hitchhiking e. Pre-zygotic barrier to speciation

9. Biogenesis was supported by... A. Redi B. Spallanzani C. Pasteur D. All of the above E. None of the above

What happened after plants first became able to live on land? A. Photosynthesis evolved as a way to produce energy. B. They adapted by developing cuticles. C. Adaptive radiation spread them into many land niches. D. Plants evolved into multicellular organisms.

Imagine that you wanted to know if speciation is more rapid in plant groups pollinated by bees or hummingbirds. To do this, you identified 20 genera of angiosperms that contained species pollinated by both types of animals. There were substantially more species in the groups that were pollinated by bees. What conclusions can you draw from your data? A) Each genus should be split into two new genera. B) The rates of speciation were similar in groups pollinated by hummingbirds and bees. C) Hummingbirds promoted speciation more than did bees. D) Hummingbirds promoted speciation less than did bees.

The Brazil nut tree, Bertholletia excels (n-17), is native to tropical rain forests of South America. It is a hardwood tree that can grow to over 50 meters tall, a source of high-quality lumber, and a favorite nesting site for harpy eagles. As the rainy season ends, tough-walled fruits, each containing 8-25 seeds (Brazil nuts), fall to the forest floor. Brazil nuts are composed primarily of endosperm. About $50 million worth of nuts are harvested each year. Scientists have discovered that the pale yellow flowers of Brazil nut trees cannot fertilize themselves and admit only female orchid bees as pollinators. The agouti (Dasyprocta spp.), a cat-sized rodent, is the only animal with teeth strong enough to crack the hard wall of Brazil nut fruits. It typically eats some of the seeds, buries others, and leaves still others inside the fruit, which moisture can then enter and allow the remaining seeds to germinate. Orchid bees are to Brazil nut trees as A) squirrels B) seed-eating birds C) rain droplets D) breezes are to pine trees.

Yeasts are members of which of the following? Ascomycota Basidiomycota imperfect fungi Chytridiomycota Zygomycota

How did he address the ongoing slave revolt in St. Domingue (later Haiti)? A. He issued a peace treaty to the leadership of St. Domingue. B. He sent French troops to overpower the rebels and capture L'Ouverture. C. He granted the colony's independence as it became the island of Haiti. D. He traveled there himself and met with the rebel leaders.

Discuss an adaptation of animals you learned about this week, or previously knew about (please limit it to invertebrates), that you think would be a useful adaptation for humans to "harness" for our own purposes. Things you may want to include in your discussion: What is the adaptation? What could we use it for? What would be some challenges in 'harnessing this adaptation for our own use? Which question would you ask your classmates that might generate further discussion? This document will be checked for plagiarism, so do not copy your answers from anywhere. Each answer MUST have at least 150 words (To count words, highlight your answer and click on Review then Word count). Write your answer in a WORD DOCUMENT AND UPLOAD IT TO THIS DROPBOX.

According to the concept of punctuated equilibrium, the "sudden" appearance of a new species in the fossil record means that speciation occurred rapidly in geologic time. the species is now extinct. the species will consequently have a relatively short existence, compared with other species speciation did not occur speciation occurred slowly in geologic time.

Rocky Mountain juniper (Juniperus scopulorum) and one-seeded juniper (J. monosperma) have overlapping ranges. If pollen grains (which contain sperm cells) from one species are unable to germinate and make pollen tubes on female ovules (which contain egg cells) of the other species, then which of these terms is applicable? reduced hybrid viability mechanical isolation behavioral isolation hybrid breakdown

Over evolutionary time, many cave-dwelling organisms have lost their eyes. Tapeworms have lost their digestive systems. Whales have lost their hind limbs. How can natural selection account for these losses? Under particular circumstances that persisted for long periods, each of these structures presented greater costs than benefits. Natural selection accounts for these losses by the principle of use and disuse. Natural selection cannot account for losses, only for innovations. The ancestors of these organisms experienced harmful mutations that forced them to find new habitats that these species had not previously used.

To apply parsimony to constructing a phylogenetic tree, base phylogenetic trees only on the fossil record, as this provides the simplest explanation for evolution choose the tree that assumes all evolutionary changes are equally probable choose the tree that represents the fewest evolutionary changes, either in DNA sequences or morphology choose the tree in which the branch points are based on as many shared derived characters as possible

Charles Darwin was the first person to propose that population growth can outpace the growth of food resources. a mechanism for evolution that was supported by evidence. that evolution occurs. a mechanism for how evolution occurs. that Earth is older than a few thousand years.

The upper forelimbs of humans and bats have fairly similar skeletal structures, whereas the corresponding bones in whales have very different shapes and proportions. However, genetic data suggest that all three kinds of organisms diverged from a common ancestor at about the same time. Which of the following is the most likely explanation for these data? Humans and bats evolved by natural selection, and whales evolved by Lamarckian mechanisms. Forelimb evolution was adaptive in people and bats, but not in whales. Whales are not properly classified as mammals. Genes mutate faster in whales than in humans or bats. Natural selection in an aquatic environment resulted in significant changes to whale forelimb anatomy.

Why do we say that populations evolve but not individuals? What is actually changing when a population evolves?

Given a population that contains genetic variation, what is the correct sequence of the following events, under the influence of natural selection? 1. Well-adapted individuals leave more offspring than do poorly adapted individuals. 2. A change occurs in the environment. 3. Genetic frequencies within the population change. 4. Poorly adapted individuals have decreased survivorship.

Which of the following statements would be accurate? YOU MAY SELECT MORE THAN ONE ANSWER. Evolution is not taking place whenever all of the conditions for the Hardy- Weinberg equilibrium are met. Evolution only affects individual organisms and does not take into account the population. Evolution will still occur even when a population is well-adapted to its environment. Evolution always causes populations to be better suited to their habitat.

Of the following anatomical structures, which is homologous to the bones in the wing of a bat? chitinous struts in the wing of a butterfly bones in the flipper of a whale cartilage in the dorsal fin of a shark Obony rays in the tail fin of a flying fish Obones in the hind limb of a kangaroo

In order for a population to evolve, natural selection must promote mutations to fit organisms' DNA all members of the population must have identical genotypes its members must have heritable genetic variation all members of the population must have identical phenotypes

Which of the following processes can result in the evolution of populations? genetic drift gene flow non-random mating natural selection all of the above

It has been observed that organisms on islands are different from, but closely related to, similar forms found on the nearest continent. This is taken as evidence that island forms and mainland forms descended from common ancestors. island forms and mainland forms have identical gene pools. the island forms and mainland forms are converging. common environments are inhabited by the same organisms.

In seedcracker finches from Cameroon, small- and large-billed birds specialize in cracking soft and hard seeds, respectively. If long-term climatic change resulted in all seeds becoming hard, what type of selection would then operate on the finch population? stabilizing selection disruptive selection No selection would operate because the population is in Hardy-Weinberg equilibrium. directional selection

Dog breeders maintain the purity of breeds by keeping dogs of different breeds apart when they are fertile. This kind of isolation is most similar to which of the following reproductive isolating mechanisms? hybrid breakdown gametic isolation habitat isolation mechanical isolation reduced hybrid fertility

You are confronted with a box of preserved grasshoppers of various species that are new to science and have not been described. Your assignment is to separate them into species. There is no accompanying information as to where or when they were collected. Which species concept will you have to use? phylogenetic ecological morphological

To begin, design a solar model that meets the given criteria: projected lifespan of the sun based on its initial mass location of nuclear fusion within the sun based on its star age and mass types of energy released due to nuclear fusion approximate ratio of hydrogen and helium in the sun's core based on its current age. Your model can be an illustration or diagram of the given criteria. You may choose to draw it freehand and photograph the drawing for your instructor, or you may use a computer program to digitally create your model. You will add your illustration/diagram to your Stars and Elements Worksheet. Be sure your model includes the items listed in the checklist below. Checklist Your model should include:

Which of the following is the BEST way for a population to maintain its genetic diversity so it can survive a change in the environment? Select one Remove mutations immediately by forcing the organism with them out. Prevent individuals living in other areas from moving into this area. Develop new beneficial traits by adapting to changes rapidly. Maintain a large number of individuals within the population.

Which of the following would ensure that two populations remain as the same species? O gene flow AND genetic bottlenecks O gene flow O genetic drift O genetic bottlenecks O vicariance events

Males and females from two different finch populations can mate with each other and produce viable, fertile offspring. The finches in both populations are blue with green spots on their wings. The finches are in different clades on a phylogenetic tree. Which species definition could be used to argue that the two populations are DIFFERENT species of finch? Phylogenetic species concept Both the morphological AND the phylogenetic species concept could be used as species definitions in this example None of the species concepts can be used to argue that they belong to different species. Any of these species concepts could be used Biological species concept Morphological species concept

Hydra, a freshwater worm-like animal related to corals, has two HOX genes. Humans have 39 HOX genes. Which of the following best explains the difference in HOX gene number between hydra and humans? A. Gene flow B. Gene loss C. Genetic drift D. Gene duplication

Which of the following was the first of the human species to roam the earth? A. Turks B. Neanderthals C. Homo erectus D. Homo rhodesiensis

What does "nomadic" mean? A. to live in a village or settlement B. living a mobile lifestyle C. relying on farming to live

What was the purpose behind the Egyptian practice of mummification? A. To prevent the deceased from achieving eternal life. B. To preserve Egyptian goods for posterity. C. To preserve a physical form to accompany the deceased's soul to the afterlife.

How many city-states made up Sumer in ancient Mesopotamia? A. 3 B. 6 C. 9 D. 12

In Athens, citizenship was reserved for those who were native-born and over the age of what? A. 15 B. 20 C. 25 D. 30