bio14

Select the correct sequence of groups for a taxonomic classification of orangutans and humans.

Eukarya - Animalia - Chordata - Mammalia - Primates - Hominidae

The relatively rapid evolution of new mammal species in response to niches that became available after the dinosaurs went extinct is an example of

adaptive radiation

Match the type of speciation on the left with its description on the right.

allopatric - no contact between the populations parapatric - populations sharing a border sympatric - continuous contact between populations

What type of selection can begin the process of parapatric speciation by favoring one phenotype in one habitat and a different phenotype in a neighboring area?

disruptive

Bacteria, Archaea, and Eukarya are the names of the three ______ of life.

domains

Select scenarios that may lead to allopatric speciation.

organisms are unable to reach part of an ecosystem where other members of the species live rising sea levels trap a population on an island rivers or glaciers divide a habitat

The study of classification is called ______, which incorporates both taxonomy and phylogenetics.

systematics

In the hierarchical classification system, a group at any rank is called a

taxon.

Systematics, the study of classification, incorporates two interrelated specialties, which are

taxonomy and phylogenetics.

The movement of ______ over time, which affected environments on Earth, has been offered as a possible explanation of mass extinctions of organisms on Earth.

tectonic plates

Suppose an error in meiosis produces diploid gametes and these gametes fuse during self-fertilization, which doubles the chromosome number. The resulting ______ organism is reproductively isolated because it will produce ______ hybrids with the parent species.

tetraploid; infertile triploid

Among the possible phylogenetic trees for a set of organisms being examined with cladistics, the most parsimonious tree is the one that requires

the fewest steps, or evolutionary changes, to construct.

Select all the true statements regarding polyploidy in plants and animals.

About 95% of ferns are natural polyploids. Polyploidy is rare in animals. About 50% of flowering plants are polyploid

A group of organisms can be referred to as being ______ if it consists of a common ancestor and all of its descendants.

monophyletic

In cladistics, a clade is a ______ group.

monophyletic

Match the cladistic terms on the left with their definition on the right.

monophyletic - group contains a common ancestor and all of the descendants paraphyletic - group contains a common ancestor and some of its descendants polyphyletic - groups that have excluded the most recent common ancestor shared by all members of the group

Match the terms on the left with the example on the right.

monophyletic - mammals paraphyletic - traditional class Reptilia polyphyletic - endothermic animals

About 50% of all flowering plants and 95% of ferns are

natural polyploids

Select all the reasons that could cause a species to go extinct.

new disease new predator habitat loss natural disaster

Match each feature of a cladogram to its correct description.

node - divergence of two species or groups from a common ancestor tips of long branches - existing species clade - any ancestor and all its descendants

Prezygotic barriers to reproduction ______, while postzygotic barriers to reproduction ______.

occur before fertilization reduce fitness of hybrid offspring

Adaptive radiation of organisms on Socotra, the Galápagos, the Malay Archipelago, and Hawaii are all examples of speciation bursts that occurred

on islands

Adaptive radiations of organisms are especially common

on islands

In cladistics, the ______ consists of comparison organisms that possess ancestral features but do not possess derived features present in the group being examined

outgroup

In cladistics, the ______ consists of comparison organisms that possess ancestral features but do not possess derived features present in the group being examined.

outgroup

Bill depth and wing length differences between populations of the little greenbul that live in the tropical rain forest and populations that live in the neighboring transitional ecotones indicate that ______ speciation might be occurring.

parapatric

If a new species begins to form when a portion of a population enters a new habitat bordering the rest of the population, this represents a case of ______ speciation

parapatric

The type of speciation that occurs when part of a population enters a new habitat bordering the range of the parent species is ______ speciation.

parapatric

What is occurring when natural selection or genetic drift acts on two populations occupying bordering areas such that, over time, the populations can no longer interbeed?

parapatric speciation

Match each type of speciation with its correct description. Instructions

parapatric speciation - occurs between populations that inhabit neighboring habitat and have minimal gene flow allopatric speciation - occurs between populations that are physically separated and do not exchange genes sympatric speciation - occurs between populations that live in the area but specialize in different environments

A(n) ______ group of organisms contains a common ancestor and some, but not all, of its descendants.

paraphyletic

If a group of species contains a common ancestor and some but not all of its descendants, it is referred to as being

paraphyletic.

In cladistic analyses, the most ______ cladogram is often regarded as the best one because it requires the fewest evolutionary changes needed to explain the data.

parsimonious

The study of evolutionary relationships among species is called

phylogenetics.

___ are evolutionary trees that are used by biologists to represent hypothesized relationships among species or groups.

phylogenies

Movements of the Earth's crust cause a shifting of continents and oceans. These shifts lead to the creation of new environments and thus affect organisms living in those environments. This ______ theory is an explanation of some mass extinctions on Earth.

plate tectonic

A group of organisms is referred to as ______ if it excludes the most recent common ancestor that is shared by all members of the group.

polyphyletic

A condition called ______ occurs when the number of sets of chromosomes increases.

polyploidy

What can lead to sympatric speciation due to doubling of chromosomes or errors in meiosis?

polyploidy

______ is rare in animals possibly because having extra chromosomes is often fatal.

polyploidy

Select the types of populations that are more vulnerable to extinction.

populations that experience a drastic climate change small populations

Assuming fertilization occurs during a mating between two different species, viable and fertile offspring are prevented by ______ barriers.

postzygotic

Hybrid inviability, hybrid infertility, and hybrid breakdown are examples of ______ reproductive barriers.

postzygotic

________ reproductive barriers occur after fertilization and reduce the fitness of the hybrid.

postzygotic

The type of speciation that occurs when populations diverge genetically while living in the same physical area is called ______ speciation.

sympatric

What type of speciation gave rise to these two species of cichlid fish that occupy the same lake but have feeding and breeding differences?

sympatric

If two fly populations live in the same field but one begins to feed on a type of fruit that matures earlier in the year while the other population prefers to feed on a later-maturing fruit, genetic divergence of the populations may lead to

sympatric speciation

Select all the organisms that possess all the characters listed in the chart.

Archaeopteryx Modern birds

A polyphyletic group excludes the most recent common ___ shared by all members of the group.

ancestor

Successful ______ is rare in animals but frequent in plants.

hybridization

Polyploidy is a condition in which

the number of sets of chromosomes has increased.

What evolutionary tree in the image represents the gradualism model of speciation?

the tree on the left

What evolutionary tree represents the punctuated equilibrium model of speciation proposed by Gould and Eldredge?

the tree on the right

How many domains of life, the most inclusive level of taxonomic hierarchy, are organisms grouped into?

three

Gossypium hirsutum, the cotton plant that is cultivated all over the world, was developed when

two species of cotton interbred and the chromosome number eventually doubled.

Rank the following in chronological order of how scientists think meteorites or comets striking Earth caused mass extinctions, beginning with the first event at the top of the list.

1. impact of meteor or comet onto Earth's surface 2. dust and debris sent into the atmosphere 3. sunlight blocked and plants die 4. animals die due to lack of shelter and food

What type of organisms appear to have evolved by gradualism, as evidenced by the fossil record?

microscopic protists

Select the common features of cladograms from the choices below.

All cladograms depict nested hierarchies of evolutionary relationships. Each node indicates where two groups arose from a common ancestor. The tips of the branches represent the taxa being studied.

___ extinction results from a gradual loss of a species as populations face new challenges, whereas ______ extinction results from the loss of a great number of species in a relatively short time period.

Background; mass

Select the true statement about the cladogram.

Birds and nonavian dinosaurs form a clade.

The current taxonomic hierarchy is based on the ideas of ______, whose hierarchical classification scheme made a lasting contribution to systematics.

Carolus Linnaeus

Select the accurate statement that defines cladistics.

Cladistics is a phylogenetic system that defines groups by distinguishing between ancestral and derived characters.

Using the chart, what organism is a common ancestor to all the other organisms, meaning that all the other organisms share an ancestral trait with it but also exhibit derived characters not present in the ancestor?

Coelophysis

What is a drawback of basing a phylogeny solely on common characteristics between organisms?

Common characteristics may be the result of convergent evolution.

Select all of the statements that correctly interpret the cladogram.

Crocodiles are more closely related to nonavian dinosaurs than they are to lizards and snakes. Birds and nonavian dinosaurs have a common ancestor.

Based on your knowledge, what was used to construct the cladogram in the figure?

DNA mutations

Select the true statement regarding the use of molecular sequence data to construct cladograms.

DNA sequence variations can be used to construct cladograms.

Select all of the following that are true of the two types of little greenbul birds that occupy neighboring habitats in the image.

Disruptive selection may be driving microevolution. Parapatric speciation may be occurring

Select the most accurate statement about gradualism and the fossil record.

For organisms such as diatoms that existed in large, connected populations, the fossil record shows a slow pace of gradual changes.

Select the true statement about punctuated equilibrium and the fossil record.

Fossils of mollusks and mammals indicate that speciation occurred in bursts followed by periods of stability.

Select all of the drawbacks of a possible sixth mass extinction caused by human activities.

Future generations will not be able to enjoy species that are extinct. Species may be lost that provide food, medicine, energy, and clean air. Ecosystems can take millions of years to recover.

Think about fish and amphibians (frogs, toads, and salamanders). Select all the statements that are correct in reference to ancestral and derived characteristics.

Gills in amphibians are homologous to gills in fish. Forelimbs would be derived in the amphibian lineage. Eggs laid in water would be ancestral.

A species becomes ______ when all members of that species have died.

extinct

Select all the situations that could lead to adaptive radiation.

Individuals are isolated on an island where there is little competition for resources. A few individuals colonize a new, isolated habitat with new resources.

Adaptive radiation may occur in what situation? Select all that apply

Individuals exploit a new habitat opportunity. Some members of a population inherit a combination of adaptations that enables them to survive a major environmental change. Some members of a population inherit an advantageous key adaptation.

Select the true statement about the set of cladograms shown in the image.

It is the same information, just presented in a different manner.

What describes allopatric speciation?

Microevolutionary forces occur in two populations that are isolated from each other, and eventually they can no longer interbreed.

If speciation is the beginning of a species, then ____ is the end of a species.

extinction

What describes the postzygotic isolating mechanism called hybrid breakdown?

Second-generation hybrid offspring are unable to reproduce.

Select all of the following that might cause smaller populations to be more vulnerable to extinction.

Small populations might contain too few beneficial alleles to withstand a challenge. Small populations inbreed more, which can bring together lethal recessive alleles. Small populations experience fewer genetic mutations.

Select the correct statement from the ones below with respect to how speciation may occur.

Speciation may be gradual or occur quickly in bursts.

Select all of the following that describe sympatric speciation.

Species utilize different microenvironments in the same location. Polyploidy produces in a tetraploid species that cannot mate with any diploid species in the same area.

Select all the correct examples of monophyletic, paraphyletic, and polyphyletic groups. Refer to the cladogram if needed.

The Protista of the domain Eukarya is paraphyletic because it excludes animals, plants, and fungi. Plants are a monophyletic group.

Select all the reasons why it is difficult for biologists to determine whether a speciation event is allopatric, sympatric, or parapatric.

The definitions of allopatric, parapatric, and sympatric speciation represent three points along a continuum. It is hard to detect all the barriers that are important to different species.

Select the statement from the choices below that accurately reflects a relationship between shared features and taxonomic levels.

The more features that two organisms have in common, the more taxonomic levels they share.

Why might a plant invest energy to produce and store nectar in extrafloral nectaries?

The nectar recruits plant-defending insects.

Select the true statement about the hierarchical system of taxonomy currently in use.

The ranks are somewhat arbitrary and do not necessarily reflect evolutionary relationships.

Select all of the reasons why the fossil record for species that evolved by punctuated equilibrium shows few transitional forms.

Transitional forms were too rare to leave any fossils. Natural processes may have destroyed many of the transitional fossils. Biological material is often poorly preserved.

True or false: Because there are eight main levels of the hierarchical system of taxonomy, most species required eight steps to evolve.

false

A taxon is a general term for

a family, order, species, or any rank in classification.

Allopatric speciation occurs when a single population is split and the two populations become isolated from each other by

a geographic barrier

Carolus Linnaeus developed a system of taxonomy in which organisms are classified into

a nested hierarchy of groups.

____ radiation is a situation in which a population inhabiting an environment with new resources gives rise to multiple specialized forms in a relatively short time.

adaptive

Caribbean anole lizards have diversified into 150 species that live on different islands and that are adapted to use different resources. These anoles provide evidence of

adaptive radiation

If a small group of birds of the same species left a continent and made it to an island with new resources, and over time diversified into 13 new species of specialized birds, this would be an example of

adaptive radiation

Speciations can happen in rapid bursts during a(n) ______, in which a population inhabiting a patchy or heterogeneous environment gives rise to multiple specialized forms in a relatively short time period.

adaptive radiation

The Devil's Hole pupfish has been geographically isolated from other pupfish for a very long time. This is an example of ______ speciation.

allopatric

The punctuated equilibrium model of speciation proposed by Gould and Eldredge fits well with the type of speciation known as ______ speciation because populations could be isolated, then diverge, and then could rejoin with ancestors but be different species.

allopatric

The type of speciation that occurs when two populations are separated by a physical barrier so that they cannot interbreed is called ______ speciation.

allopatric

What mechanism of speciation is considered the most common because the evidence for it is abundant?

allopatric

_____ speciation is a type of speciation in which a barrier physically separates a population into two groups that cannot interbreed.

allopatric

______ speciation resulted in the diversification of tortoises on different Galápagos islands, eventually leading to 11 different subspecies.

allopatric

Rank the three types of speciation, from the form with complete reproductive isolation at the top to the form with continuous intermingling of the species at the bottom.

allopatric parapatric sympatric

Match the type of speciation on the left with its correct figure on the right, using the letters on the diagram.

allopatric speciation - no contact between populations parapatric speciation - populations share a border area sympatric speciation - continuous contact between populations

In cladistics, ___ characters are inherited attributes that resemble those of past relatives of the organism, whereas ___ characters are features that are different from those found in the group's past relatives

ancestral, derived

The impact theory suggests that mass extinctions in Earth's history may be due to

meteorites that crashed to Earth.

According to the fossil record, there were about 0.1 to 1.0 extinctions per year per million species; this type of ______ extinction accounts for most extinctions overall.

background

in cladistics, a ___ is a monophyletic group of species consisting of a common ancestor and all of its descendants.

clade

In phylogenetic analyses, a group of species united by a single evolutionary pathway is called a(n)

clade.

The ______ approach creates phylogenies based on shared derived characters and ancestral characters.

cladistic

A diagram depicting evolutionary relationships based on shared derived characters is called a

cladogram

Historical relationships rather than similarities of the organisms is the emphasis of a

cladogram

What is the correct name of the figure below?

cladogram

In cladistics, the outgroup is the

comparator organisms that do not possess the derived traits being examined.

Cladistics bases evolutionary trees on ______ features, which are different from those found in a group's ancestor, and ______ features, which resemble those found a group's ancestor.

derived; ancestral

What is taxonomy?

describing and naming organisms

Select all the areas covered by the definition of taxonomy.

describing organisms classifying organisms naming organisms

In parapatric speciation, disruptive selection may favor

different phenotypes in different habitats.

Select all of the following that are true about adaptive radiation.

different types of new resources available different adaptations simultaneously selected for rapid speciation

Select the correct order of the taxonomic groups from the most inclusive to the most specific from the choices below.

domain, kingdom, phylum, class, order, family, genus, species

The increased rate of extinctions due to human activities may have effects that are difficult to predict because of the many interactions in ______, on which humans and other species rely.

ecosystems

As the image shows, mass extinctions have had the greatest influence on Earth's history because

enormous adaptive radiation can occur after mass extinction

The root cause of extinction is when microevolution in a species doesn't keep up with

environmental change

Phylogenies are trees of organisms that depict hypotheses about

evolutionary relationships.

The geologic timescale indicates that there have been ______ mass extinctions in the past 500 million years.

five

In a cladistic analysis of terrestrial vertebrates, what feature would be considered ancestral?

four limbs

Select mechanisms that can cause polyploidy.

gametes from two different species fuse meiosis fails, leading to diploid gametes that fuse during self-fertilization

Select all the examples of prezygotic isolation mechanisms.

gametic isolation mechanical isolation

Select three ways that genetic divergence can occur between two separated populations.

genetic drift natural selection mutation

Small, incremental changes over numerous generations is the model of speciation described by Darwin and is known as

gradualism.

Match the type of prezygotic reproductive barrier on the left with its example on the right.

habitat isolation - herbivorous ladybird beetles feed on different types of plants temporal isolation - field crickets mature at different times behavioral isolation - frog mating calls differ

What may be causing a current sixth mass extinction on Earth at a rate of about 20 to 200 extinctions per million species per year?

humans

Select all the postzygotic reproductive barriers.

hybrid breakdown hybrid inviability hybrid infertility

Match the postzygotic reproductive barrier on the left with its description on the right. Instructions

hybrid inviability - Embryo may die before reproductive maturity. hybrid infertility - Hybrid is not able to produce offspring. hybrid breakdown - The offspring of hybrids in future generations have abnormalities.

Match the postzygotic reproductive barrier on the left with its example on the right.

hybrid inviability - hybrid eucalyptus seeds do not germinate; seedlings die very early hybrid infertility - the offspring of a lion-tiger mating (liger) is infertile hybrid breakdown - offspring of hybrid mosquitoes have abnormal genitalia

Plants often can form viable ______ between species, whereas it is very rare for this to occur in animals.

hybrids

A cladogram depicts

hypothesized evolutionary relationships.

The two theories that attempt to explain the causes of mass extinctions on Earth are the ______ theory and the movement of the Earth's crust due to ______.

impact; plate tectonics

Mass extinction is the loss of species

in large numbers over a short time.

Select the element that is common in meteorites but rare on Earth, which provides evidence to support the impact theory of mass extinction on Earth.

iridium

Movement of Earth's tectonic plates and the impact theory are two explanations for Earth's

mass extinctions

If two species of plants live in the same place but have flowers that attract different pollinators such that the two species never interbreed, what reproductive isolating mechanism is operating?

mechanical isolation

The element iridium, which appears as a thin layer on many parts of Earth, provides the evidence that ______, which may have led to mass extinctions.

meteorites impacted the surface of the Earth

If a zygote cannot form between two organisms, then a type of __________ reproductive barrier is present.

prezygotic

Select all of the following that are prevented by postzygotic reproductive barriers.

production of fertile offspring survival of offspring to maturity

Allopatric speciation seems to support what model of speciation?

punctuated equilibrium

What model of speciation proposes that bursts of rapid evolution give rise to species and are followed by long periods of little change?

punctuated equilibrium

Select all the ways in which humans are creating situations that cause extinctions of animals and plants on Earth.

releasing pollution into the atmosphere and water fragmentation of habitat introducing nonnative species into new habitats destruction of habitat

Mechanisms of ______ prevent successful reproduction and include prezygotic barriers and postzygotic barriers.

reproductive isolation

A cladogram is a treelike diagram that shows hypothesized evolutionary relationships among organisms based on

shared derived characteristics

Select all of the following that were used in the past to construct evolutionary trees.

similarities in characteristics as many characteristics as possible

Low genetic diversity, fewer genetic mutations, and inbreeding are characteristic of ______ populations, and any one of these could lead to extinctions of those populations.

small

Select the population that would be most at risk of extinction.

small population in a quick-changing environment

Allopatric, parapatric, and sympatric are types of ______ in which populations genetically diverge and reproductive barriers arise.

speciation

Two different models of ______ are gradualism and punctuated equilibrium.

speciation

Select all the characteristics of allopatric speciation.

speciation that occurs in isolated bodies of fresh water most common mechanisms of speciation accounts for diversification of organisms on islands

Select all of the following that describes background extinction.

steady, gradual loss of species accounts for most extinctions of species

According to this chapter's Investigating Life essay, an extrafloral nectary is a structure that ______ and is not a ______.

stores nectar; flower

What definition best describes phylogenetics?

studying evolutionary relationships among species

If a population diverges genetically from its parent population while remaining in the same physical area, this is an example of _____ speciation

sympatric

Polyploidy is one mechanism of ______ speciation among plants because new species can arise due to errors in meiosis and fusion of gametes from two different species.

sympatric