Chapter 22

Mutations are always __________.

a change in an individual's DNA

Prefix for equal-

equi-

prefix for true, good

eu-

prefix for same

homo-

Darwin and Wallace made independent observations in different parts of the world. Which statements are true?

-Both observed slightly different species on nearby islands and concluded that species could change over time. -Both witnessed nature up close and realized it was a battlefield with massive casualties. -Both collected huge numbers of specimens and realized that individuals vary within species.

In the lab, Nachman examined dark mice from two different populations living hundreds of miles apart. The mice looked nearly identical. Their dark color was caused by two different genes. What does this tell you?

-Dark fur color evolved independently on each lava flow. -Under very similar conditions, natural selection can favor very similar adaptations. -Two completely different mutations in two separate genes can generate the same phenotype. -There are at least two genes involved in creating dark mouse fur.

What does Dr. Carroll mean when he says, "while mutation is random, natural selection is not"?

-Natural selection acts on traits. -Natural selection favors some mutations. -Mutations for advantageous traits are more likely to be passed on to the next generation.

After his journey on the HMS Beagle, Darwin made this now-famous sketch in his notebook. Which ideas does it represent? There is a sketch made by Darwin. In this sketch, there is a line labeled 1 and it branches into several branches. These branches divide as well, and so on. Descendants of each of the initial branches are composed of a group labeled from A to D.

-Species descend from other species just as naturally as children come from parents. -All species are linked to one another by common ancestry. -All species are connected to one another in a "family tree."

Identify the four postulates of natural selection.

-Survival and reproductive success are variable among individuals in a population. -Individuals with certain traits are more likely to survive and reproduce. -Individuals in a population vary in the traits they possess. -Some trait differences are heritable.

Which observations led Darwin to establish a relationship between extinct and living animals?

-The fossilized remains of giant sloths were found in places where smaller sloths now live. -The bony shells of armadillos resembled the shells of ancient Glyptodon fossils. Darwin puzzled over why he found fossils of extinct animals in places where he found similar, living animals. Eventually, these observations supported his idea that today's species descend from older, extinct species.

Which term describes the ability of a trait to be passed on to offspring?

Heritability (Heritability is the ability of a trait to be passed on to offspring.)

What did Wallace conclude from observing that the bones in manatee flippers look similar to the bones in a human arm and hand?

Manatees' arm and finger bones are evidence that manatees share a common ancestor with land mammals. (For Wallace, the unnecessary arm and finger bones in manatee flippers show that they descended from an ancestor with arms. These vestigial structures are evidence that every species is a modified form of an older species.)

When Charles Darwin set sail on the HMS Beagle, what did he and most of his contemporary scientists think about the origin of species?

Most scientists, including Darwin, thought each species was specially created by God in its present form and did not change over time. (Special creation was the prevailing idea of the time. Darwin, like most other scientists, began his journey believing species were unchanging and specially created by God.)

Which of the following statements about natural selection is true? Natural selection can be used by farmers to generate organisms with desirable traits. Natural selection favors individuals that reproduce more than others. Natural selection is a process whereby genes are selected randomly for preservation in the next generation. Natural selection occurs in opposition to evolution.

Natural selection favors individuals that reproduce more than others. (Individuals who are better able to survive and reproduce are more likely to be selected for than individuals who don't survive or cannot reproduce.)

Does the ability of a Mycobacterium tuberculosis cell to infect a new host depend on its drug-resistant phenotype?

No, drug-susceptible cells and drug-resistant cells are equally likely to infect a new host. (A cell's drug susceptibility or resistance does not affect its ability to infect another host, although a cell's drug resistance would increase that cell's chances to spread in an environment containing antibiotics due to increased survival.)

In the United States today, about half of the corn crop is genetically engineered with a protein that is toxic to corn borers, an insect pest of corn. Which of the following conditions would be necessary for evolution of resistance to the toxic protein to occur in the corn borer?

The corn borer must have or generate (by mutation) heritable variation in resistance to the toxic protein. The resistant corn borers must survive better or reproduce more than nonresistant corn borers.

what describes the evolution by natural selection of Mycobacterium tuberculosis bacteria in their new environment?

The drug-resistance trait is an adaptation to the environment in which human hosts are medicated with the antibiotic rifampin. (Bacterial cells have higher fitness when they are drug resistant in the new environment in which people have been medicated with antibiotics.)

True or false? It would be difficult to assess whether the drug-susceptible or drug-resistant phenotype in a population of Mycobacterium tuberculosis was more fit in an environment without antibiotics.

True In an environment without antibiotics, individual cells probably would not differ in their reproductive rates or their survival. Without the application of the drug (antibiotic), it would be very difficult to analyze any differences—one wouldn't even be able to sort the cells!

Which pair of chickens should a farmer breed to produce larger chickens?

large hen, large rosster

prefix for father

pater or patr-

root word for chromosomes

ploid

prefix for many

poly-

prefix for behind

post-

Charles Darwin _____. proposed natural selection as the mechanism of evolution was the first person to conclude that organisms evolve was the first to realize that fossils are remains of ancient organisms eagerly published his theory before it was well-developed proposed that unused parts of the body deteriorate

proposed natural selection as the mechanism of evolution (Although Wallace submitted his work for publication first, Darwin's work was known to have pre-dated Wallace's work and was much more detailed; therefore, Darwin was given credit for the theory.)

prefix for first

proto-, prim-

prefix for same

sym-

Which of the following organisms could be produced by artificial selection? A cow that produces a large quantity of milk. A chimpanzee that communicates through sign language. A rabbit that is housebroken. A dog that serves as the "eyes" for a blind individual.

A cow that produces a large quantity of milk

prefix for with or together with

co-

what would be an example of direct observation of evolutionary change? -development of drug resistance in bacteria -discovery of shells of extinct species -discovery of transitional forms of horses -same genetic code in fireflies and tobacco plants -vestigial pelvis in right whales -similarities in mammalian forelimbs -similarity of endemic island species to nearby mainland species -the high concentration of marsupial species in Australia

development of drug resistance in bacteria

A challenge to traditional (pre-1860) ideas about species came from embryology, when it was discovered that _____.

embryos of dissimilar organisms, such as sharks and humans, resemble each other

Darwin and Wallace independently arrived at the same conclusion that species change over time. Which observations supported their conclusions?

-Tortoises from different Galapagos islands have distinct shells. -Mockingbirds from different Galapagos islands had subtle, consistent differences. -Bird families clustered geographically: cockatoos in the Malay Archipelago and Australia, macaws and hummingbirds in the Americas. -The fossilized remains of giant sloths were similar to the smaller, living sloths Darwin encountered. -The bony shells of armadillos resembled fossilized shells from the extinct Glyptodon. -Birdwing butterflies were found throughout the Malay archipelago, but species differed slightly from island to island.

what would be an example of fossil record? -development of drug resistance in bacteria -discovery of shells of extinct species -discovery of transitional forms of horses -same genetic code in fireflies and tobacco plants -vestigial pelvis in right whales -similarities in mammalian forelimbs -similarity of endemic island species to nearby mainland species -the high concentration of marsupial species in Australia

-discovery of shells of extinct species -discovery of transitional forms of horses

suffix for foot

-pod

what would be an example of homology? -development of drug resistance in bacteria -discovery of shells of extinct species -discovery of transitional forms of horses -same genetic code in fireflies and tobacco plants -vestigial pelvis in right whales -similarities in mammalian forelimbs -similarity of endemic island species to nearby mainland species -the high concentration of marsupial species in Australia

-same genetic code in fireflies and tobacco plants -vestigial pelvis in right whales -similarities in mammalian forelimbs

what would be an example of biogeography? -development of drug resistance in bacteria -discovery of shells of extinct species -discovery of transitional forms of horses -same genetic code in fireflies and tobacco plants -vestigial pelvis in right whales -similarities in mammalian forelimbs -similarity of endemic island species to nearby mainland species -the high concentration of marsupial species in Australia

-similarity of endemic island species to nearby mainland species -the high concentration of marsupial species in Australia

Which term describes a trait that increases an individual's ability to survive in a particular environment?

Adaptation (An adaptation is a trait that increases an individual's ability to survive in a particular environment.)

The wing of a bat is homologous to the _____ of a whale.

Flipper

As Wallace traveled the Malay Archipelago, he noticed that western islands had placental mammals, like monkeys. Eastern islands had marsupial mammals, like kangaroos. How did Wallace explain this distribution?

The western islands were once connected to Asia and the eastern islands had been connected to Australia. The islands had never been connected to each other. (Different kinds of animals were restricted to different regions because species come from pre-existing, nearby species. Because the western islands were once all connected, they would have the same species, which are also found in the mainland in Asia. The eastern islands were once also all connects and had the same species, which are also found in Australia.)

Why do dark-colored rock pocket mice on dark lava flows have white bellies?

There is no selection for dark bellies by visual predators.

Why did dark-colored rock pocket mice first appear in a population of light-colored rock pocket mice?

They have a genetic mutation that affects their fur color.

prefix for other

allo-

prefix for two, double, both

amphi-

prefix for joint

athr-

From his observations of organisms in the Galapagos islands, Darwin reasoned that _____.

organisms had adapted to new environments, giving rise to new species (Darwin reasoned that natural selection had increased the match between the organisms and their environment.)