Evolution

EvidenceHow Natural Selection works

Organizing from Kingdom -> Species

Evolution

• Theory that all living things descended from a common ancestor (all life is related)

• Happens by a very very small changes over verrrrryyyyy long time.

• Natural Selection is the process that makes evolution happen.

Evidence for Evolution

• Fossils– Bones show small changes over time

• DNA/Proteins– Closely related animals have similar DNA

• Body parts– Closely related animals have similar features, bones etc.

• Embryos – Developing babies all look very similar

How does Natural Selection work?

• Variation (everyone looks a little different)– Meiosis, Sexual reproduction, mutations brings variety

• Over reproducing– In nature, too many babies are made

• Competition– For food, space, mates etc

• Survival of fittest– Those with the “best” traits, survive, reproduce more and

pass their successful traits to offspring

If all life is related, who is closest related?

• Those in the same Species are the closest related.• How can you tell if they are the same species?– They can reproduce together and make fertile offspring– If they cannot do this they are not the same species.

• The next group above species is called Genus• Every organisms has a 2 part name in italics that is made

of their genus and species.– Ex. dog - Canis familiaris Canis = genus; familiaris= species

Organizing all life into groups…

From biggest Remember It!!!Kingdom KingPhylum PhillipClass Came Order OverFamily ForGenus GreenSpecies Soup

to smallest

PREPARE TO READ!!!• Most Evolution questions have long stories to

read about different animals and how they have changed.

• DON’T PANIC• You do not have to know what the animal is.

The information you need is in the reading!!!• As you read the question think about the

evidence for evolution, how natural selection works and what makes the most sense

A species of newt produces a toxin that can kill predators. Scientists have observed that some garter snakes can feed on the newts because they have a natural resistance to the toxin.

In areas where populations of newts and garter snakes interact, which of the following predictions is best supported by evolutionary theory?

A. The garter snakes with resistance to the toxin will successfully reproduce and pass the trait on to their offspring.B. The garter snakes without resistance to the toxin will acquire resistance by increasing the rate at which they feed on the newts.

C. The newts that produce low levels of toxin will also develop camouflage adaptations that allow them to hide from the garter snakes.

D. The newts will stop making the toxin rather than continue to use energy to make a toxin that is ineffective against the garter snakes.

A species of newt produces a toxin that can kill predators. Scientists have observed that some garter snakes can feed on the newts because they have a natural resistance to the toxin.

In areas where populations of newts and garter snakes interact, which of the following predictions is best supported by evolutionary theory?

A. The garter snakes with resistance to the toxin will successfully reproduce and pass the trait on to their offspring.

At one time, all the continents on Earth were joined in a supercontinent called Pangaea. Over time Pangaea split into separate continents.

Which of the following statements describes a result of this split?

A. All fossil evidence of species from Pangaea was lost.B. Organisms on the separated continents no longer migrated for breeding.

C. Ancestral organisms evolved into different species on the separated continents.D. Evolution in species proceeded more slowly on the separate continents than it had on Pangaea.

At one time, all the continents on Earth were joined in a supercontinent called Pangaea. Over time Pangaea split into separate continents.

Which of the following statements describes a result of this split?

C. Ancestral organisms evolved into different

species on the separated continents.

Long-tailed weasels and European otters are both classified into the family Mustelidae. Which of the following types of information was most likely used to classify these animals into the same family?

A. food source

B. skeletal structure C. location of habitat D. method of movement

Long-tailed weasels and European otters are both classified into the family Mustelidae. Which of the following types of information was most likely used to classify these animals into the same family?

B. skeletal structure

Tough question, but B is the only answer that is about the actual animal appearance, not its behavior or environment.

Scientific evidence shows that modern dogs, wolves, and foxes all have a common ancestor. Further evidence shows that dogs are more closely related to wolves than to foxes.

Which of the following observations provides the best evidence that dogs are more closely related to wolves than to foxes?

A. The diets of dogs and wolves are more similar than the diets of dogs and foxes.

B. The life spans of dogs and wolves are more similar than the life spans of dogs and foxes.

C. The genetic sequences of dogs and wolves are more similar than the genetic sequences of dogs and foxes.

D. The body sizes of dogs and wolves are more similar than the body sizes of dogs and foxes.

Scientific evidence shows that modern dogs, wolves, and foxes all have a common ancestor. Further evidence shows that dogs are more closely related to wolves than to foxes.

Which of the following observations provides the best evidence that dogs are more closely related to wolves than to foxes?

C. The genetic sequences of dogs and wolves are

more similar than the genetic sequences of dogs and foxes.

Which of the following is the best example of natural selection?

A. The lifespan of a chimpanzee is extended to 60 years in captivity.

B. The population size of giraffes changes over time as a result of immigration.

C. The bone density of a human increases significantly as a result of participation in sports.

D. The average toxin level in a poisonous frog population increases over time in response to high predation.

Which of the following is the best example of natural selection?

D. The average toxin level in a poisonous frog

population increases over time in response to high predation.

The diagram shows many finch species that originated from a single ancestral finch species in the Galápagos Islands.Which of the following statements best explains why many different finch species originated

from the single ancestral species? A. Populations adapted to environmental pressures. B. Recessive traits in populations were eliminated over

time. C. Individuals acquired unique characteristics during

their lifetimes. D. Random mutation caused some individuals to have

harmful traits.

The diagram shows many finch species that originated from a single ancestral finch species in the Galápagos Islands.Which of the following statements best explains why many different finch species

originated from the single ancestral species?

A. Populations adapted to environmental pressures.

Adapt means to change (environmental pressure =

natural selection)

Which of the following statements is correct about the hierarchy of the taxonomic system currently used to classify organisms?

A. All organisms of a given order belong to the same species.

B. Many different classes of organisms belong to the same order.

C. All organisms of a given phylum belong to the same kingdom.

D. Many different families of organisms belong to the same genus.

Which of the following statements is correct about the hierarchy of the taxonomic system currently used to classify organisms?

C. All organisms of a given phylum belong to the same kingdom.

Kingdom is bigger than phylum, so all in a phylum

must be the same kingdom

(Compare to all people in Roxbury are in Boston, because Boston is a bigger group that includes Roxbury)

Whale fins and bat wings are anatomically similar. Which of the following does this suggest about the animals?

A. Whales and bats move in the same way.

B. Whales and bats have a common ancestry. C. Whales and bats have existed for the same

amount of time. D. Whales and bats were once adapted to the same

environment.

Whale fins and bat wings are anatomically similar. Which of the following does this suggest about the animals?

B. Whales and bats have a common ancestry.

Similar body parts is one of the evidence pieces for evolution

Which of the following is the best scientific evidence that mammals evolved from reptiles?

A. similarities in the diets of extinct reptiles and modern mammals

B. similarities in the average life spans of modern reptiles and modern mammals

C. fossils of ancient reptiles and mammals that appear together in the same layers of rock

D. fossils that show gradual changes in skull shape from reptile-like organisms to mammal-like organisms

Which of the following is the best scientific evidence that mammals evolved from reptiles?

D. fossils that show gradual changes in skull shape from reptile-like organisms to mammal-like organisms

Which of the following statements best explains why the chestnut-sided warbler, Dendroica pensylvanica, and the cerulean warbler, Dendroica cerulea, are classified as closely related species?

A. They eat the same types of insects.

B. They have similar DNA sequences. C. They show similarities in their nesting behaviors. D. They live in the same types of woodland

habitats.

Which of the following statements best explains why the chestnut-sided warbler, Dendroica pensylvanica, and the cerulean warbler, Dendroica cerulea, are classified as closely related species?

B. They have similar DNA sequences.

Look for evidence of evolution

The smooth-skinned, leaf-tailed gecko lives on Madagascar, an island off the coast of Africa. The gecko hunts at night and sleeps on trees by day. The color and pattern of the gecko’s body resembles leaves.

Which of the following statements best explains how the gecko’s unique body color and pattern evolved?

A. All the geckos needed to look like leaves in order to live in trees and therefore acquired the necessary trait.

B. Individuals with bodies that looked the most like leaves interbred only with other green or brown lizard species.

C. Gene sequences of all the geckos mutated to produce the leaf appearance when ancestral geckos moved from mud to trees.

D. Individuals with bodies that looked the most like leaves were better able than other individuals to avoid predators and passed on the trait.

The smooth-skinned, leaf-tailed gecko lives on Madagascar, an island off the coast of Africa. The gecko hunts at night and sleeps on trees by day. The color and pattern of the gecko’s body resembles leaves.

Which of the following statements best explains how the gecko’s unique body color and pattern evolved?

D. Individuals with bodies that looked the most

like leaves were better able than other individuals to avoid predators and passed on the trait.

The scientific name for the cougar is Puma concolor. Which of the following organisms is most closely related to the cougar?

A. Corythaixoides concolor

B. Lynx rufus C. Panthera tigris D. Puma yagouaroundi

The scientific name for the cougar is Puma concolor. Which of the following organisms is most closely related to the cougar?

D. Puma yagouaroundi

Don’t over think it, They both belong to the Genus “Puma”

Two groups of very similar-looking finches are found on the Galápagos Islands. One group of finches is found only on Floreana Island. The other group of finches is found on several of the islands, including Floreana Island. On Floreana Island, these two groups of finches do not interbreed.

Which of the following conclusions is best supported by this information?

A. The two groups of finches have the same song. B. The two groups of finches are different species. C. The two groups of finches adapted to eat the same

foods. D. The two groups of finches descended from different

ancestors.

Two groups of very similar-looking finches are found on the Galápagos Islands. One group of finches is found only on Floreana Island. The other group of finches is found on several of the islands, including Floreana Island. On Floreana Island, these two groups of finches do not interbreed.

Which of the following conclusions is best supported by this information?

B. The two groups of finches are different species.

An extinct shark named Scapanorhynchus existed over 100 million years ago. It had a long snout, sharp teeth, and a long tail fin.

Which of the following statements explains how scientists most likely learned this information about Scapanorhynchus?

A. They studied fossilized remains of Scapanorhynchus. B. They analyzed the DNA sequence of

Scapanorhynchus. C. They looked at the skeletons of modern sharks that

live where Scapanorhynchus lived. D. They studied the anatomy of other aquatic animals

that lived when Scapanorhynchus lived.

An extinct shark named Scapanorhynchus existed over 100 million years ago. It had a long snout, sharp teeth, and a long tail fin.

Which of the following statements explains how scientists most likely learned this information about Scapanorhynchus?

A. They studied fossilized remains of Scapanorhynchus.

Some areas of a forest contain rich soil, while in other areas the soil is poor. Plants of a certain species grow taller in the rich soil than in the poor soil. The taller plants receive more sunlight and are able to produce more offspring than the shorter plants. If these offspring grow in rich soil, they are tall, but if they grow in poor soil, they are short.

Which of the following statements best explains why this situation is not an example of evolution by natural selection?

A. The observed differences in plant height are not due to genetics.

B. The differences in soil conditions do not affect all plants equally.

C. The short plants and tall plants are not isolated enough from each other.

D. The short plants are not accumulating gene mutations as quickly as the tall plants.

Some areas of a forest contain rich soil, while in other areas the soil is poor. Plants of a certain species grow taller in the rich soil than in the poor soil. The taller plants receive more sunlight and are able to produce more offspring than the shorter plants. If these offspring grow in rich soil, they are tall, but if they grow in poor soil, they are short.

Which of the following statements best explains why this situation is not an example of evolution by natural selection?

A. The observed differences in plant height are not due to genetics.

Over time, a type of plant called Darwin’s orchid has evolved a long, 28 cm nectar tube on its flowers. A particular species of moth pollinates the Darwin’s orchid.

Which of the following evolutionary changes was most likely favored in the moth because of its relationship with the Darwin’s orchid?

A. faster flying speeds in the moths B. larger average size of the moths’ eyes C. longer average length of the moths’ tongues D. more elaborate mating behaviors in the moths

Over time, a type of plant called Darwin’s orchid has evolved a long, 28 cm nectar tube on its flowers. A particular species of moth pollinates the Darwin’s orchid.

Which of the following evolutionary changes was most likely favored in the moth because of its relationship with the Darwin’s orchid?

C. longer average length of the moths’ tongues

In 2006, scientists discovered fossilized skeletons of an animal with several interesting features. Fossil evidence indicated that the animal not only had scales, fins, and gills, but also had lungs, a full set of ribs, and limb bones arranged to support the animal’s weight. The illustration below shows what the animal, called Tiktaalik, probablylooked like based on the fossil evidence.

Which of the following statements best explains why the Tiktaalik fossils are an important piece of evidence for evolution?

A. They include skeletons of both males and females. B. They are complete skeletons of a carnivorous animal. C. They allow scientists to estimate the animal’s lifespan. D. They show a transitional form between fish and land-

dwelling vertebrates

Fossil evidence indicated that the animal not only had scales, fins, and gills, but also had lungs, a full set of ribs, and limb bones arranged to support the animal’s weight. The illustration below shows what the animal, called Tiktaalik, probablylooked like based on the fossil evidence.

Which of the following statements best explains why the Tiktaalik fossils are an important piece of evidence for evolution?

D. They show a transitional form between fish and land-dwelling vertebrates

Until recently, the myrtle warbler and the Audubon’s warbler were thought to be separate species of birds because the males have very different appearances. Which of the following observations most likely led to the reclassification of these warblers as one species?

A. The myrtle warbler and the Audubon’s warbler have the same diet.

B. The myrtle warbler and the Audubon’s warbler lay the same number of eggs.

C. The myrtle warbler and the Audubon’s warbler have overlapping geographical ranges.

D. The myrtle warbler and the Audubon’s warbler interbreed and produce fertile offspring.

Until recently, the myrtle warbler and the Audubon’s warbler were thought to be separate species of birds because the males have very different appearances. Which of the following observations most likely led to the reclassification of these warblers as one species?

D. The myrtle warbler and the Audubon’s warbler interbreed and produce fertile offspring.

In the deserts of the southwestern United States, rock formations made from lava flows are found scattered across the sand. The rock pocket mouse, which has dark fur, lives on the black lava rocks. The Apache pocket mouse, which has light fur, lives on the tan sand.

Which of the following statements best explains how these two types of mice could have evolved from a common ancestor?

A. Individual mice changed their fur color to escape their predators.

B. Natural selection favored different fur colors in the different habitats.

C. The emigration of mice changed the gene pools in the original population.

D. The original population of mice spread out geographically to relieve overcrowding.

In the deserts of the southwestern United States, rock formations made from lava flows are found scattered across the sand. The rock pocket mouse, which has dark fur, lives on the black lava rocks. The Apache pocket mouse, which has light fur, lives on the tan sand.

Which of the following statements best explains how these two types of mice could have evolved from a common ancestor?

B. Natural selection favored different fur colors in

the different habitats.

The scientific name for the woodchuck is Marmota monax, and the scientific name for the long-tailed marmot is Marmota caudata. Which of the following statements describes the taxonomic relationship between the woodchuck and the long-tailed marmot?

A. They belong to different phyla.

B. They belong to the same genus. C. They belong to the same species. D. They belong to different families.

The scientific name for the woodchuck is Marmota monax, and the scientific name for the long-tailed marmot is Marmota caudata. Which of the following statements describes the taxonomic relationship between the woodchuck and the long-tailed marmot?

B. They belong to the same genus.

There names tell you it is the genus Marmota

The bones that make up the forelimbs of monkeys, cats, whales, and birds are similar. Which of the following statements best supports the evolutionary relationship of these animals?

A. The animals have different ancestries but have adapted to similar environments.

B. The animals share a common ancestry but have adapted to different environments.

C. The animals at one time lived in different environments but now share an environment.

D. The animals use their forelimbs for identical activities but live in different environments.

The bones that make up the forelimbs of monkeys, cats, whales, and birds are similar. Which of the following statements best supports the evolutionary relationship of these animals?

B. The animals share a common ancestry but have

adapted to different environments.

A population is separated into two groups by a geographic barrier. Over time, enough differences develop between the two groups that they do not interbreed when reunited.

Which of the following terms best describes the process that has occurred?

A. extinction

B. hybridization C. immigration D. speciation

A population is separated into two groups by a geographic barrier. Over time, enough differences develop between the two groups that they do not interbreed when reunited.

Which of the following terms best describes the process that has occurred?

D. speciation

Spines and thorns on plants look similar, and both provide protection from herbivores. However, not all plants with spines or thorns have descended from a recent common ancestor. Spines are modified leaves, and thorns are modified stems.

Which of the following statements best describes how this information provides evidence for evolution?

A. It shows that different organisms sometimes look alike.

B. It shows that herbivores are the strongest selection force on organisms.

C It shows that a variety of structures can be effective in protecting an organism from herbivores.

D. It shows that environmental pressures can cause unrelated organisms to change in similar ways.

Spines and thorns on plants look similar, and both provide protection from herbivores. However, not all plants with spines or thorns have descended from a recent common ancestor. Spines are modified leaves, and thorns are modified stems.

Which of the following statements best describes how this information provides evidence for evolution?

D. It shows that environmental pressures can cause

unrelated organisms to change in similar ways.

A researcher is comparing amino acid sequences for the protein hemoglobin from several primate species. What does the degree of similarity in sequences among the primate species indicate about these species?

A. how closely related they areB. how frequently they interbreed

C. how rapidly they can evolve in the futureD. how efficient their circulatory systems are

A researcher is comparing amino acid sequences for the protein hemoglobin from several primate species. What does the degree of similarity in sequences among the primate species indicate about these species?

A. how closely related they are

Amino Acids and building proteins comes from the DNA. Similar DNA is evidence for evolution

In Asia, human population growth and land development have fragmented forest habitats. Because of this fragmentation, tigers have become geographically isolated in small populations, and the tigers repeatedly mate within the same small population of tigers.

Which of the following is the most likely impact this isolation will have on tiger populations?

A. Genetic diversity of each tiger population will decrease, threatening survival.

B. Adaptation of each tiger population to its present environment will occur rapidly.

C. The tigers in each population will breed more often, increasing population size.

D. The tigers in each population will mate with closely related species to maximize breeding success.

In Asia, human population growth and land development have fragmented forest habitats. Because of this fragmentation, tigers have become geographically isolated in small populations, and the tigers repeatedly mate within the same small population of tigers.

Which of the following is the most likely impact this isolation will have on tiger populations?

A. Genetic diversity of each tiger population will decrease, threatening survival.

Scientists recovered the body of a woolly mammoth from the frozen soil of Siberia. The DNA sequence of the woolly mammoth was very similar to the DNA sequence of the African elephant.

Which of the following conclusions is best supported by this information?

A. African elephants evolved directly from woolly mammoths.

B. The woolly mammoth and the African elephant have a common ancestor.

C. Woolly mammoths had the same number of chromosomes as African elephants.

D. The woolly mammoth and the African elephant should be classified as the same species.

Scientists recovered the body of a woolly mammoth from the frozen soil of Siberia. The DNA sequence of the woolly mammoth was very similar to the DNA sequence of the African elephant.

Which of the following conclusions is best supported by this information?

B. The woolly mammoth and the African elephant

have a common ancestor.

Which of the following characteristics is most useful when classifying a eukaryote into a kingdom?

A. how the organism feeds

B. how the organism moves C. the organism’s color and mass D. the organism’s form and structure

Which of the following characteristics is most useful when classifying a eukaryote into a kingdom?

A. how the organism feeds

Remember Kingdoms are separated by autotrophs and heterotrophs.

Two populations of fruit flies both belong to the genus Drosophila. The fruit flies are able to successfully mate within their own populations, but males from one population are unable to mate and produce offspring with females from the other population.

Based on this information, which of the following statements could describe the fruit flies in the two populations?

A. They are classified as different orders. B. They are classified in different classes. C. They are classified as different species. D. They are classified in different kingdoms.

Two populations of fruit flies both belong to the genus Drosophila. The fruit flies are able to successfully mate within their own populations, but males from one population are unable to mate and produce offspring with females from the other population.

Based on this information, which of the following statements could describe the fruit flies in the two populations?

C. They are classified as different species.

Odontomachus bauri is a species of ant that has a trap jaw that shuts rapidly. This jaw system evolved from basic mouth parts that all ants have, but the jaw is longer, the joint is a different shape, and the muscles are larger.

Which of the following statements best explains why this trap-jaw trait evolved?

A. The trap jaw increases the ants’ body mass. B. The trap jaw allows the ants to eat only one kind of

food. C. The trap jaw is the ants’ only means of species

recognition. D. The trap jaw increases the ants’ chances of survival

and reproduction.

Odontomachus bauri is a species of ant that has a trap jaw that shuts rapidly. This jaw system evolved from basic mouth parts that all ants have, but the jaw is longer, the joint is a different shape, and the muscles are larger.

Which of the following statements best explains why this trap-jaw trait evolved?

D. The trap jaw increases the ants’ chances of survival and reproduction.

About 70 years ago, cane toads were introduced to Australia. The toads are toxic to some species of snakes, such as Dendrelaphis punctulatus. The longer an individual snake is, the greater its chance of survival after eating a cane toad.

Which of the following did scientists most likely observe in the D. punctulatus snake population as a result of the presence of the cane toads?

A. The entire population was killed by the toads. B. The entire population became resistant to the

toads. C. The average body length in the population

increased. D. The average body length in the population

decreased.

About 70 years ago, cane toads were introduced to Australia. The toads are toxic to some species of snakes, such as Dendrelaphis punctulatus. The longer an individual snake is, the greater its chance of survival after eating a cane toad.

Which of the following did scientists most likely observe in the D. punctulatus snake population as a result of the presence of the cane toads?

C. The average body length in the population

increased.• Carefull reading is the best way to answer this!

Antibiotic resistance can vary within a population of bacteria. The diagram below represents the changes in a population of bacteria as a result of exposure to an antibiotic over time.

The changes in the population are most likely the result of which of the following?

A. exponential growth B. genetic crosses C. immigration D. natural selection

Antibiotic resistance can vary within a population of bacteria. The diagram below represents the changes in a population of bacteria as a result of exposure to an antibiotic over time.

The changes in the population are most likely the result of which of the following?

D. natural selection

The fossil record supports which of the following descriptions of the evolution of life on Earth?

A. Life first appeared with the diversity found today.

B. The importance of natural selection diminished over time.

C. Complex organisms evolved from more simple organisms.

D. Large organisms appeared before single-celled organisms.

The fossil record supports which of the following descriptions of the evolution of life on Earth?

C. Complex organisms evolved from more simple

organisms.

Which of the following statements gives the most likely explanation for the presence of two very similar species of squirrels living on opposite sides of the Grand Canyon?

A. One squirrel traveled across the canyon and started a new population on the other side.

B. One squirrel traveled across the canyon and interbred with a different population on the other side.

C. Members of a single squirrel species were geographically separated by the formation of the canyon.

D. Members of two different squirrel species migrated from two different places to opposite sides of the canyon.

Which of the following statements gives the most likely explanation for the presence of two very similar species of squirrels living on opposite sides of the Grand Canyon?

C. Members of a single squirrel species were

geographically separated by the formation of the canyon.

The Asian shore crab invaded parts of the eastern coast of the United States about 15 years ago. The Asian shore crab preys on blue mussels. In the time since the Asian shore crab arrived, the average shell thickness has increased in the blue mussel population.

Which of the following is the most likely reason that this increase in shell thickness has occurred?

A. Blue mussels with thick shells attract more crabs than mussels without thick shells.

B. Blue mussels with thick shells grow in larger colonies than mussels without thick shells.

C. Blue mussels with thick shells catch more food per day than mussels without thick shells.

D. Blue mussels with thick shells survive and reproduce more successfully than mussels without thick shells.

The Asian shore crab invaded parts of the eastern coast of the United States about 15 years ago. The Asian shore crab preys on blue mussels. In the time since the Asian shore crab arrived, the average shell thickness has increased in the blue mussel population.

Which of the following is the most likely reason that this increase in shell thickness has occurred?

D. Blue mussels with thick shells survive and

reproduce more successfully than mussels without thick shells.

A species of parasitic fly follows the sounds that male crickets make with their wings. The flies deposit their larvae in the crickets’ bodies. As the larvae develop and emerge from the crickets’ bodies, the crickets die.

Researchers have discovered a genetic mutation in some crickets that changes their wing structure and makes them silent. The crickets with silent wings are found among crickets with normal wings when it is time to mate.

According to evolution by natural selection, which of the following will most likely occur in the cricket population, based on the selection pressure from the flies?

A. Male crickets with silent wings will increase in frequency. B. The frequency of the silent wing mutation will stay the

same. C. Male crickets with normal wings will learn to make new

sounds. D. A new mutation will create spikes on the crickets’ wings to

keep the flies away.

A species of parasitic fly follows the sounds that male crickets make with their wings. The flies deposit their larvae in the crickets’ bodies. As the larvae develop and emerge from the crickets’ bodies, the crickets die.

Researchers have discovered a genetic mutation in some crickets that changes their wing structure and makes them silent. The crickets with silent wings are found among crickets with normal wings when it is time to mate.

According to evolution by natural selection, which of the following will most likely occur in the cricket population, based on the selection pressure from the flies?

A. Male crickets with silent wings will increase in frequency.

In humans, the appendix is small and is not needed for digestion. In rabbits, the appendix is well developed and is used in the digestion of plant fibers.

Which of the following provides the best scientific explanation for the presence of the appendix in both humans and rabbits?

A. Rabbits and humans live in environments with similar conditions.

B. Rabbits and humans are both eukaryotes with similar cell structures.

C. The appendix is evolving into a new type of organ in rabbits and humans.

D. The appendix is inherited from a common ancestor of rabbits and humans.

In humans, the appendix is small and is not needed for digestion. In rabbits, the appendix is well developed and is used in the digestion of plant fibers.

Which of the following provides the best scientific explanation for the presence of the appendix in both humans and rabbits?

D. The appendix is inherited from a common

ancestor of rabbits and humans.