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Which of the following is an example of a vestigial structure?
All of the above are examples of vestigial structures.
What did Charles Darwin discover?
The main mechanism by which evolution occurs.
Artificial selection was used on corn to produce a single strain of corn with increased growth rates and greater resistance to a fungus. Although farmers have continued to select for these traits, however, the productivity of this strain is no longer increasing. This suggests that:
all or most of the natural variation for these traits has been eliminated.
Prior to the 19th century, most scholars thought that the world was less than 10,000 years old. Based on geological and radiometric evidence, however, scientists now believe the age of Planet Earth is closer to:
approximately 4 billion years old
Many vertebrate animals have the same arrangements of bones in their forelimbs. This is considered to be evidence for evolution because:
similarities among vertebrate forelimbs suggest that they evolved from a common ancestor
Everyone, including scientists, used to believe that the Sun and other planets revolve around the Earth. Why was this idea a hard one to drop when Copernicus and Gallileo found evidence that the sun was the center of the solar system?
The original idea was consistent with ordinary observations of how the Sun looks as it rises and sets B)
The evidence for a sun-centered solar system was complicated and indirect.D)
The idea of an earth-centered solar system was consistent with the belief that humans were the most important thing in the universe.
Natural selection can only act on traits
that are heritable.
Which of the following statements is NOT important to Darwin's theory of natural selection?
Offspring tend to inherit characteristics acquired by their parents during their lifetimes
An oak tree produces two kinds of leaves: large with shallow lobes and narrow with deep lobes. If this dimorphism is caused completely by environmental influences and there is no genetic difference between leaves that express either of the two forms, then:
natural selection cannot act on the trait of leaf morphology.
A population's environment sometimes changes too quickly for natural selection to adapt the individuals in the population to the environment. In these situations
Extinction Happens.
The longer two species have been evolving on their own, the greater the number of _____________________ that accumulate between them.
genetic differences
Evolution is defined as
a change in the frequency of alleles in a population over time.
Which best describes the evidence for evolution?
Scientists are continually finding new evidence for evolution, particularly in rapidly evolving organisms like bacteria.
Which of the following traditional ideas were obstacles to thinking about evolution?
That species never change.

That the earth has always been exactly the same.

That some species are more important than others.

That the earth is not very old.
The phenotype of an organism is:
its physical characteristics.
Evolutionary change as a result of natural selection ALWAYS leads to:
Is not Not uniformity. higher gas mileage.
increased complexity.perfection.
Which of the following is the best measure of an organism's fitness
the number of offspring it produces
The contribution of a genotype or phenotype to the genetic composition of subsequent generations relative to other genotypes or phenotypes best describes which of the following concepts?
"Survival of the fittest" may be a misleading phrase to describe the process of evolution by natural selection because:
survival matters less to natural selection than reproductive success does.
Which of the following traits CANNOT be modified through artificial selection on a laboratory population?
None of the above; all could be modified through artificial selection
Many mosquito populations today are resistant to pesticides that were historically effective. This pesticide resistance arose in these populations because:
some individuals were resistant to the pesticides before they were used, and those mosquitoes were more likely to survive and reproduce.
For a population to evolve through natural selection:
its members must possess inheritable variation.
From an evolutionary perspective, behavior can be viewed best as:
a trait that has a biological basis, and thus can evolve.
What is the difference between artificial selection and natural selection?
Artificial selection requires human intervention, whereas natural selection does not require human intervention.
A population is
a group of individuals of the same species that have the potential to interbreed.