Biology 2, Chapter 22

A farmer wishes to develop a strain of high-yield corn that is also resistant to drought. He has the following individuals from the current year's crop: Individual A—Yield: 179 bushels/acre; drought resistance: high Individual B—Yield: 220 bushels/acre; drought resistance: low Individual C—Yield: 185 bushels/acre; drought resistance: medium Individual D—Yield: 140 bushels/acre; drought resistance: high Individual E—Yield: 200 bushels/acre; drought resistance: medium Which of the following crosses would produce the highest corn yield with the highest resistance to drought?

A and E

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

Adaptation

A population of zooplankton is exposed to a small number of predatory fish that feed on the larger-sized (adult) zooplankton. Which of the following predictions would most likely occur based on the principles of natural selection?

Adult zooplankton will start to reach sexual maturity when they are still relatively small

Which of the following people developed the idea known as the scala naturae, or scale of nature?

Aristotle

The modern idea of extinction as a common occurrence in Earth's history was first proposed in the early 19th century writings of __________.

Cuvier

How did Hutton and Lyell's ideas influence Charles Darwin's thinking?

Darwin reasoned that the earth must be very old and that slow, subtle processes could produce substantial biological changes

Paleontology, the study of fossils, was developed by __________.

Georges Cuvier

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

Heritability

What must be true of any organ described as vestigial?

It must be homologous to some feature in an ancestor.

Which of the following statements about natural selection is true?

Natural selection favors individuals that reproduce more than others.

The upper forelimbs of humans and bats have fairly similar skeletal structures, whereas the corresponding bones in whales have very different shapes and proportions. However, genetic data suggest that all three kinds of organisms diverged from a common ancestor at about the same time. Which of the following is the most likely explanation for these data?

Natural selection in an aquatic environment resulted in significant changes to whale forelimb anatomy.

What insight did Darwin gain from reading Thomas Malthus's essay on human suffering?

Organisms have the capacity to over-reproduce.

Which of the following is correct regarding natural selection?

Over time, natural selection can increase the correspondence between organisms and their environments, If an environment changes, or if individuals move to a new environment, natural selection may result in adaptation to these new conditions, sometimes giving rise to new species. Natural selection is a process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than do individuals without those traits. Individuals do not evolve; populations do.

Which of the following is not an observation or inference on which natural selection is based?

Poorly adapted individuals never produce offspring.

Currently, two extant elephant species (X and Y) are classified in the genus Loxodonta, and a third species (Z) is placed in the genus Elephas. Thus, which statement should be true?

Species X and Y share a greater number of homologies with each other than either does with species Z.

Over long periods of time, many cave-dwelling organisms have lost their eyes. Tapeworms have lost their digestive systems. Whales have lost their hind limbs. How can natural selection account for these losses?

Under particular circumstances that persisted for long periods, each of these structures presented greater costs than benefits.

All known organisms transcribe genetic information to protein molecules via the same genetic code. This finding strongly supports the hypothesis that __________.

all organisms are descended from a single common ancestor

The breeding of plants and animals for particular traits by humans is called __________.

artificial selection

The role that humans play in artificial selection is to _____.

choose which organisms reproduce

Even though rodents known as sugar gliders and flying squirrels are members of distinctly different groups of organisms and live on different continents, they possess similar characteristics. This is an example of __________.

convergent evolution

Darwin originally defined evolution as __________.

descent with modification

Darwin and Wallace's theory of evolution by natural selection was revolutionary because it _____.

dismissed the idea that species are constant and emphasized the importance of variation and change in populations

An important challenge to traditional (pre-1860) ideas about species was the observation that seemingly dissimilar organisms such as hummingbirds, humans, and whales have similar skeletal structures. This most directly suggested to biologists that __________.

dissimilar organisms might have evolved from a distant, common ancestor

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

Organisms found only in specific places in the world are referred to as __________.

endemic

What does it mean to describe evolution as a scientific theory?

evolution is a broad model that is supported by many observations and much experimental evidence

After the drought of 1977, researchers on the island of Daphne Major hypothesized that medium ground finches that had large, deep beaks, survived better than those with smaller beaks because they could more easily crack and eat the tough Tribulus cistoides fruits. If this hypothesis is correct, what would you expect to observe if a population of these medium ground finches colonizes a nearby island where Tribulus cistoides is the most abundant food for the next 1000 years? Assume that (1) even the survivors of the 1977 drought sometimes had difficulty cracking the tough T. cistoides fruits and would eat other seeds when offered a choice; and (2) food availability is the primary limit on finch fitness on this new island.

evolution of yet larger, deeper beaks over time

Animals that possess homologous structures probably __________.

evolved from the same ancestor

How does our understanding of genetics today refute Lamarck's principle of the inheritance of acquired characteristics?

experiments in genetics show that traits acquired during an individuals lifetime are not inherited in the way proposed by Lamarck

At the time Darwin voyaged on the HMS Beagle, the popularly accepted theory in Western culture that explained the origin of Earth's plants and animals held that the various species __________.

had been created by divine intervention a few thousand years before

On an evolutionary tree, __________.

homologous characteristics form a nested pattern

Structures as different as human arms, bat wings, and dolphin flippers contain many of the same bones, which develop from similar embryonic tissues. These structural similarities are an example of _____.

homology

Adaptations are defined as __________.

inherited characteristics of organisms that enhance their survival and reproduction in specific environments

Which of the following is not an observation or inference that Darwin made while developing his theory of evolution?

interactions between individuals and their environment cause individuals to evolve

It has been observed that organisms on islands are different from, but closely related to, similar forms found on the nearest continent. This is taken as evidence that ____.

island forms are descended from mainland forms

Darwin's explanation of how adaptations arise centered on __________.

natural selection

In Darwin's view of descent with modification, __________.

natural selection can improve the match between an organism and its environment

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

organisms had adapted to new environments, giving rise to new species

A(n) __________ is the smallest unit that can evolve.

population

Charles Darwin _____.

proposed natural selection as the mechanism of evolution

The bacteria Staphylococcus aureus has developed resistance to some antibiotic drugs. How did this resistance come about?

some members of the bacteria populations possessed some sort of genetic variation for antibiotic resistance that was selected for when the bacteria was exposed to the drug

Carolus Linnaeus is considered to be the founder of __________, and he __________.

the binomial classification system; thought that resemblances among different species reflected the pattern of their creation

What does each branch point on an evolutionary tree represent?

the common ancestor of the lineages beginning there and to the right of it

During periods of rapid environmental change, what may happen to a species that was well-suited to the former environment?

traits that were favorable in the original environment may be detrimental in the new environment, the species may go extinct, the population may change so much in adapting to the new environment that it is considered a new species, individuals with particular traits that provide an advantage in the new environment will have a higher reproductive success.

If x indicates the fossils of two closely related species, neither of which is extinct, then their remains may be found in how many of these strata?

two strata

Which of the following evidence most strongly supports the common origin of all life on Earth? All organisms _____.

use essentially the same genetic code

Homologies that appear to have marginal, if any, importance to an organism are called __________.

vestigial structures