Title: History of Life
Course: Question Banks

Q: According to ________, increased reproductive success is based on traits favored by a particular environment.
- evolution (Incorrect. Evolution is much more than just reproductive success in a particular environment.)
- sexual selection (Incorrect. Sexual selection involves mating choices based on variable characteristics in the opposite sex.)
- natural selection (Correct. The key idea here is favorable traits are situationally dependent (only matched to a particular environment).)
A: natural selection

Q: One of the foundational concepts of natural selection was an essay on ________.
- geological time scales (Incorrect. While Darwin had read works on geological time scales and knew the earth was very old, this was not as key to the development of his ideas on natural selection.)
- the Black Plague and rats (Incorrect. Darwin did not base his ideas on an essay about the Black Plague and rats.)
- human economic pressures (Correct. Thoma Malthus’ work led directly to one of the three principles of natural selection.)
A: human economic pressures

Q: One of the principles of ________ is that organisms will compete for resources.
- evolution (Incorrect. Evolution is much more than just competition for resources.)
- sexual selection (Incorrect. Sexual selection involves mating choices based on variable characteristics in the opposite sex.)
- natural selection (Correct. Competition for resources is a central principle of natural selection; this competition is a selective pressure.)
A: natural selection

Q: ________ is recognized as the father of evolution but ________ also helped develop the idea.
- Alfred Wallace; Thomas Malthus (Incorrect. Wallace is not the father of evolution.)
- Thomas Malthus; Peter Grant (Incorrect. Thomas Malthus was an economist, not the father of genetics.)
- Charles Darwin; Alfred Wallace (Correct. Darwin is the father of evolution; Wallace developed similar ideas and discussions between the two helped refine and hone the idea.)
A: Charles Darwin; Alfred Wallace

Q: A trait that increases the environmental fitness of an organism is called a ________.
- advantage (Incorrect. Scientists do not call such traits advantages.)
- asset (Incorrect. Scientists do not call such traits assets.)
- adaptation (Correct. Scientists use the term adaptation to describe a trait with a positive impact on environmental fitness.)
A: adaptation

Q: In order for organisms to change over generations, there must first be ________.
- environmental pressure (Incorrect. Environmental pressure can change what features of an organism give it an advantage but they are not the force behind the observed changes.)
- competition (Incorrect. Competition is a type of selective pressure, but not the source of observed changes.)
- genetic variation (Correct. Genetic differences generate changes in organisms; these changes can be adaptive or not, depending on selective pressures.)
A: genetic variation

Q: When two species evolve in unique directions from a common point, the process of ________ is at work.
- convergent evolution (Incorrect. Convergent means “together,” which indicates two species evolve in a similar direction.)
- selective pressure (Incorrect. While selective pressures are part of evolution, they are not a process.)
- divergent evolution (Correct. Divergent evolution results in two species evolving in different directions from a common point.)
A: divergent evolution

Q: Populations change over time by ________, while species arise by ________.
- microevolution; speciation (Incorrect. Speciation is the term for when a new species appears in the tree of life, but this is not the process.)
- macroevolution; microevolution (Incorrect. Microevolution is focused on a smaller scale than new species.)
- microevolution; macroevolution (Correct. Changes in populations over time are driven by microevolution, while macroevolution describes the process that gives rise to new species and higher taxonomic groups with divergent characteristics.)
A: microevolution; macroevolution

Q: Structures with no apparent function in a modern organism are ________.
- redundant (Incorrect. Redundant indicates a structure does have a function, which is shared by another structure.)
- leftover (Incorrect. Scientists do not call these structures leftover.)
- vestigial (Correct. Vestigial structures have no apparent, modern function.)
A: vestigial

Q: Fossil evidence allows scientists to determine ________.
- exactly when an organism lived (Incorrect. There is nothing “exact” about fossil evidence.)
- when an organism died (Incorrect. Scientists can suggest when an organism likely died but there is no way to determine when that actually happened.)
- when organisms lived relative to each other (Correct. Organisms can be sequenced (before, concurrent, after) using fossil evidence.)
A: when organisms lived relative to each other

Q: Typically, islands are ________ for increased evolutionary pressures.
- a neutral setting (Incorrect. Islands are not neutral in terms of evolutionary pressures.)
- a poor setting (Incorrect. The isolation of islands do not make them a poor setting for evolutionary pressures.)
- an ideal setting (Correct. Islands tend to have unique life forms not found elsewhere due to their isolation and unique selective pressures.)
A: an ideal setting

Q: Species that are ________ will have a lot of genetic similarities.
- have similar needs (Incorrect. Just having similar needs will not correlate with genetic similarities. We all need air after all.)
- located in the same habitat (Incorrect. Just living in the same habitat will not correlate with genetic similarities.)
- closely related (Correct. Genetic similarities will occur more often in closely related organisms and species.)
A: closely related

Q: A common misconception about evolution is that ________.
- genetic mutations are always passed on to the next generation (Incorrect. Genetic mutations are not always passed along to the next generation.)
- it does not have a goal (Incorrect. This is true, not a misconception.)
- environmental changes cause genetic mutations (Correct. Many people incorrectly believe that the environment can force genes to change in a directed fashion.)
A: environmental changes cause genetic mutations

Q: During ________, populations change over time.
- mutation (Incorrect. Mutations occur in individuals, not populations.)
- adaptation (Incorrect. Adaptations occur in individuals, not populations.)
- evolution (Correct. Populations change over evolutionary time.)
A: evolution

Q: Evolution is fundamentally a ________.
- change in the environment that cause genetic changes (Incorrect. This is a better definition of natural selection.)
- change in biological habitats (Incorrect. Changing biological habitats are selective pressures.)
- change in gene variation over time (Correct. Genes are the basis for the adaptations that natural selection works upon; over time these variations shift in relative abundance in a population. This is evolution.)
A: change in gene variation over time

Q: Rottweilers and poodles are members of the same ________ because they can interbreed and produce fertile, viable offspring.
- genus (Incorrect. Members of the same genus are not necessarily capable of producing fertile, viable offspring.)
- family (Incorrect. While technically true, this is not the best answer choice.)
- species (Correct. This is the biological species definition: the ability to interbreed and produce fertile, viable offspring.)
A: species

Q: The offspring of two different species is known as a ________.
- mutt (Incorrect. Mutt is a term used in dog breeding to describe a dog of unknown (or mixed) ancestry.)
- subspecies (Incorrect. A subspecies is a smaller population of a species that usually shows a fairly permanent geographical isolation.)
- hybrid (Correct. The offspring from reproduction between two different species is known as a hybrid.)
A: hybrid

Q: Ultimately, species remain separate because they do not share ________.
- geographical ranges (Incorrect. Some individual species do appear in multiple distinct geographical locations; consider humans for example.)
- physical features (Incorrect. Separate species may share a number of physical features; consider bald eagles and African fishing eagles.)
- gene pools (Correct. The basis to any change in a group or population must be genetic; organisms that can interbreed and produce fertile offspring will mix gene pools.)
A: gene pools

Q: After speciation occurs, populations ________.
- must no longer interact (Incorrect. Speciation can occur even when populations or groups continue to interact.)
- thrive under different environmental pressures (Incorrect. Speciation can occur when populations are exposed to the same environments; this happens often in plants in fact.)
- are incapable of interbreeding (Correct. In order for speciation to occur, two populations, from one original group, must evolve in such a way that it is impossible for them to interbreed.)
A: are incapable of interbreeding

Q: The basis of allopatric speciation is ________.
- reproductive isolation (Incorrect. Populations are reproductively isolated after speciation events, but this is not what generates allopatric speciation.)
- adaptative radiation (Incorrect. Adaptive radiation can occur as multiple species evolve from a single parental species, but this is not the basis of allopatric speciation.)
- geographic separation of populations (Correct. Allopatric speciation involves a parental species being physically divided into two separate populations and subsequent evolution of these populations.)
A: geographic separation of populations

Q: ________ occurs within populations that continue to inhabit the same space.
- Allopatric speciation (Incorrect. Allopatric speciation requires geographic separation.)
- Reproductive isolation (Incorrect. Reproductive isolation does not necessarily occur within cohabiting populations.)
- Sympatric speciation (Correct. Sympatric speciation occurs within populations that still cohabit.)
A: Sympatric speciation

Q: The process of ________ results in two species uniting into a single species.
- reinforcement (Incorrect. Reinforcement strengthens separation of species that continue to interbreed until hybridization is prevented.)
- stability (Incorrect. Stability occurs when fit hybrids can be produced by two interbreeding species yet the two remain distinct species.)
- fusion (Correct. Fusion describes the breakdown of reproductive barriers, resulting in two species combining into one.)
A: fusion

Q: In hybrid zones, two distinct species ________.
- unite into a single species (Incorrect. This does not necessarily happen. Sometimes the species reach stability or reinforcement.)
- produce fit hybrids that maintain separate lineages (Incorrect. This does not necessarily occur in hybrid zones. Sometimes the lineages join into a single species.)
- continue to produce offspring with one another (Correct. In hybrid zones two species may continue to produce offspring with each other. Usually this will eventually result in either fusion or stability.)
A: continue to produce offspring with one another

Q: ________ occurs when fit hybrids, which are produced by distinct species, maintain separate lineages.
- Reinforcement (Incorrect. Reinforcement strengthens separation of species that continue to interbreed until hybridization is prevented.)
- Fusion (Incorrect. Fusion describes the breakdown of reproductive barriers, resulting in two species combining into one.)
- Stability (Correct. Stability occurs when fit hybrids can be produced by two interbreeding species yet the two remain distinct species.)
A: Stability

Q: According to the ________ model, species diverge over long spans of time by incremental changes.
- punctuated equilibrium (Incorrect. Under the punctuated equilibrium model, a new species undergoes rapid changes from the parent species and then is largely unchanged for a long period.)
- sliding (Incorrect. There is no sliding model of speciation.)
- gradual speciation (Correct. The gradual speciation model argues for small steps leading to species divergence over time.)
A: gradual speciation

Q: Which model of speciation is shown in the following image?
- gradual speciation (Incorrect. The gradual speciation model argues for small steps leading to species divergence over time.)
- sliding (Incorrect. There is no sliding model of speciation.)
- punctuated equilibrium (Correct. Under the punctuated equilibrium model, a new species undergoes rapid changes from the parent species and then is largely unchanged for a long period.)
A: punctuated equilibrium

Q: The main driver behind changes in the rate of speciation is ________.
- the rate of genetic mutations (Incorrect. Genetic mutations generally occur at the same rate in different organisms, leading to no change in the rate of speciation.)
- an organism’s lifespan (Incorrect. Speciation occurs by “generational” time, not lifespan time.)
- environmental stability (Correct. Environmental stability, or changes, provide the main pressures that select for different characteristics which may result in speciation. Therefore the rate at which an environment changes can cause changes in the rate of speciation in that environment.)
A: environmental stability

Q: Population genetics focuses on studying changes in ________.
- epistatic genes (Incorrect. Epistatic genes may be examined in population genetics, as can other types of genes.)
- species diversity (Incorrect. Population genetics usually focuses within a single species, not across species.)
- allele frequencies (Correct. Population genetics focuses on changes in allele frequencies that in turn will drive changes in populations.)
A: allele frequencies

Q: The ________ is the sum of all the alleles in a population.
- genotypic frequencies (Incorrect. This is a measure of the relative percentages of individual alleles.)
- gene bank (Incorrect. This is a scientific repository of DNA samples.)
- gene pool (Correct. The gene pool is the sum of all the alleles (genes) in a population.)
A: gene pool

Q: A ________ may occur with no obvious selective pressures at work.
- founder effect (Incorrect. A founder effect is a specific event that results in a portion of a population becoming isolated; isolation generates unique selective pressures.)
- mutation (Incorrect. Mutations always occur independent of selective pressures; selective pressures then work on those genetic variations in inherited traits.)
- genetic drift (Correct. Genetic drifts are random changes in allele frequencies that convey no advantage (or disadvantage) to the population.)
A: genetic drift

Q: According to the Hardy-Weinberg principle, allele frequencies ________.
- in constant flux (Incorrect. The Hardy-Weinberg principle does not state allele frequencies are constantly changing.)
- have no impact on speciation (Incorrect. The Hardy-Weinberg principle does not address speciation at all.)
- are stable unless exposed to an evolutionary force (Correct. The Hardy-Weinberg principle emphasizes allele frequencies will not change unless “pushed” by an evolutionary force.)
A: are stable unless exposed to an evolutionary force

Q: Population geneticists are most interested in ________.
- allele frequencies (Incorrect. Allele frequencies are simply a way of studying the genetics of a population.)
- genetic sequences (Incorrect. Genotypes, allele frequencies, and phenotypes can all be studied without knowing the actual sequence of A, T, G, or C controlling these frequencies.)
- genetic structure (Correct. Population geneticists are most interested in the frequency of genotypes as they relate to the distribution of phenotypes.)
A: genetic structure

Q: A population is said to be in equilibrium if ________.
- the overall size remains the same (Incorrect. Population size can change without affecting equilibrium.)
- no migration occurs (Incorrect. This is one aspect of equilibrium but not the whole picture.)
- no evolutionary forces influence it (Correct. A population enters Hardy-Weinberg equilibrium if no evolutionary forces act upon it. Note that this never happens in real life, so the Hardy-Weinberg principle is just a mathematical (theoretical) baseline of a population’s allele frequencies.)
A: no evolutionary forces influence it

Q: Heritability refers to ________.
- a trait being genetically controlled (Incorrect. Nearly all traits are at least influenced by genetic factors.)
- the effect of chance on a phenotype (Incorrect. This relates more to genetic drift.)
- the phenotypic variation due to genetic differences (Correct. The fraction of phenotypic variation due to genetic differences is known as heritability.)
A: the phenotypic variation due to genetic differences

Q: ________ populations are more susceptible to genetic drift.
- Interbreeding (Incorrect. Interbreeding has little to do with genetic drift.)
- Large (Incorrect. Large populations are less impacted by random changes in allele frequencies.)
- Small (Correct. Chance changes have a larger impact on smaller populations or samples.)
A: Small

Q: Individuals often choose to mate with partners who are phenotypically similar to them. This type of mate choice is known as ________.
- geographical selection (Incorrect. Geographical variation describes phenotypic variations between populations in different locations; there is no such term as geographical selection.)
- sexual dimorphism (Incorrect. This describes the situation in which the male and female form of a species are quite different, such as peacocks and peahens.)
- assortative mating (Correct. Assortative mating occurs when individuals choose mates similar to themselves.)
A: assortative mating

Q: A mouse population that originally ranges from white to black becoming mostly grey over several generations is an example of what type of selection?
- directional (Incorrect. Directional selection moves the population to one phenotype from another.)
- diversifying (Incorrect. Diversifying selection moves the population to two (usually opposite) phenotypes.)
- stabilizing (Correct. Stabilizing selection moves the population to an intermediate phenotype.)
A: stabilizing

Q: Which of the following is an example of directional selection?
- a flower population that originally ranges from white to red becoming mostly pink over several generations (Incorrect. This would be stabilizing selection.)
- a moth population that is originally grey gradually dividing into discrete white and black populations over several generations (Incorrect. This would be diversifying selection.)
- a mouse population that is originally white in color becoming darker in color after several generations (Correct. Directional selection moves the population to one phenotype from another.)
A: a mouse population that is originally white in color becoming darker in color after several generations

Q: ________ is the sum of various forces which may not all be adaptive.
- Mutation (Incorrect. Mutation is simply a change in a DNA sequence.)
- Natural selection (Incorrect. Natural selection is based off adaptations to environments.)
- Evolution (Correct. Not all forces at work in evolution are adaptive; some can lead to extinction.)
A: Evolution

Q: ________ summarizes the evolution of various life forms on earth
- A taxonomy (Incorrect. This is a hierarchical arrangement of things, including organisms.)
- A scientific name (Incorrect. The scientific name is just the universally accepted name for a specific organism.)
- A phylogenetic tree (Correct. A phylogenetic tree is a visual summary of evolutionary relationships.)
A: A phylogenetic tree

Q: Phylogenetic trees ________.
- identify specific changes leading to new species (Incorrect. Phylogenetic trees can contribute to our understanding of species differences but that is all.)
- confirm working hypotheses about species relationships (Incorrect. Phylogenetic trees are themselves hypotheses, not confirmation of one.)
- show the evolutionary connections among organisms (Correct. A phylogenetic tree is a visual summary of evolutionary relationships.)
A: show the evolutionary connections among organisms

Q: A(n) ________ phylogenetic tree has a single lineage at the base.
- unrooted (Incorrect. An unrooted tree simply shows relationships between species.)
- branched (Incorrect. Phylogenetic trees are always branched because distinct species are represented by individual branches.)
- rooted (Correct. A rooted tree has a single lineage at the base (or root).)
A: rooted

Q: An unrooted phylogenetic tree ________.
- has a single lineage at the base (Incorrect. This would be a rooted tree.)
- does not show relationships between species (Incorrect. All phylogenetic trees show relationships between species.)
- shows relationships but not lineage between species. (Correct. An unrooted tree simply shows relationships between species.)
A: shows relationships but not lineage between species.

Q: What is the most specific taxonomic category?
- genus (Incorrect. Genus is not the most specific taxonomy category.)
- domain (Incorrect. Domain is actually the least specific taxonomic category.)
- species (Correct. Species is the most specific designation in taxonomy.)
A: species

Q: The ________ system uses a hierarchical model for classification.
- Darwinian (Incorrect. There is no Darwinian classification.)
- Mendelian (Incorrect. There is no Mendelian classification.)
- Linnaean (Correct. The Linnaean system is hierarchical, with increasingly specific designations for an organism.)
A: Linnaean

Q: The Linnaean taxonomic system is ________.
- static (Incorrect. The current taxonomic designation are not set in stone.)
- being forsaken (Incorrect. The Linnaean system is still in use with biologists.)
- fluid (Correct. The current taxonomic designations can, and are, updated as new evidence comes to light.)
A: fluid

Q: Scientists studying shared anatomical features are looking at ________.
- redundant structures (Incorrect. Redundant structures do not play a key role in examining shared anatomical features.)
- vestigial structures (Incorrect. The shared anatomical features may not be vestigial ones.)
- homologous structures (Correct. Homologous indicates “like” or “similar”; for comparing anatomical features associated with evolutionary changes, scientists need to look at homologous structures, like all the arm bones.)
A: homologous structures

Q: ________ structures have a similar function; ________ have a similar embryonic origin.
- Homologous; analogous (Incorrect. Analogous structures do not have a similar embryonic origin.)
- Analogous; homoplastic (Incorrect. Analogous and homoplastic describe the same concept: similarities that are not due to evolutionary relationships.)
- Analogous; homologous (Correct. Homologous structures are connected by evolution and have a similar origin. Analogous structures are similar because they need to do the same thing in different lineages.)
A: Analogous; homologous

Q: Molecular systematics works best when used ________.
- as a standalone measure of evolutionary relationships (Incorrect. Some DNA matches can occur by random chance. After all, there is only so many ways to string together the four nucleotides.)
- as a verification of phenotype-based relationships (Incorrect. Molecular systematics is not used to verify phenotype based relationships since analogous structures (same phenotype) may not share the same genetics.)
- in conjunction with morphologic information (Correct. Molecular systematics works best when the molecular data is partnered with form and function (morphologic) evidence.)
A: in conjunction with morphologic information

Q: A clade is a group of organisms ________.
- that share analogous features (Incorrect. Analogous features are not connected evolutionarily; therefore they cannot influence a clade.)
- that share derived characteristics (Incorrect. Clades do not always contain organisms with all the same derived characteristics.)
- descended for a single ancestor (Correct. This defines a clade.)
A: descended for a single ancestor

Q: Phylogenies are based on the idea of ________.
- minimum parsimony (Incorrect. Minimum parsimony is not used in phylogenetics.)
- molecular systematics (Incorrect. While many modern phylogenies use molecular information, it is possible to develop a phylogeny without any DNA or biochemical information.)
- maximum parsimony (Correct. Maximum parsimony is the idea that events occur in the simplest, most obvious way. All phylogenies are based on this idea.)
A: maximum parsimony

Q: A ________ can also be called a monophyletic group.
- domain (Incorrect. Domains are definitely not monophyletic as they group many diverse groups together.)
- kingdom (Incorrect. Kindgoms are not necessarily monophyletic; they may group quite diverse organisms together.)
- clade (Correct. Clades are always monophyletic, or based on features not shared with other groups.)
A: clade

Q: The first phylogenetic tree was constructed by ________.
- Linnaeus (Incorrect. While Linnaeus is the father of taxonomy, he did not construct any phylogenetic trees.)
- Woese (Incorrect. Woese is responsible for our current three-domain approach to organizing biological life but he did not construct the first phylogenetic tree.)
- Darwin (Correct. Darwin sketched the first phylogenetic tree in 1837.)
A: Darwin

Q: Horizontal gene transfer is considered particularly important in the evolution of ________.
- eukaryotes (Incorrect. HGT is much more limited in the eukaryotic domain.)
- all life on Earth (Incorrect. Life had to arise on Earth before genes could be transferred vertically or horizontally.)
- prokaryotes (Correct. HGT occurs often in prokaryotic organisms; this complicates a true understanding of prokaryotic phylogenetics.)
A: prokaryotes

Q: The first eukaryotic cells may have evolved due to ________.
- horizontal gene transfer (Incorrect. HGT does not explain how eukaryotes evolved but does impact prokaryotic evolutionary studies.)
- a ring of life model (Incorrect. This is simply a proposed phylogenetic model that abandons any idea of a tree or web of life in favor of studying the three domains as outshoots of a primitive pool of prokaryotes. It incorporates both HGT and genome fusion.)
- genome fusion (Correct. This hypothesis remains under heavy debate but it is possible that eukaryotes arose following genome fusion of different prokaryotes to generate an endosymbiotic organism.)
A: genome fusion