Natural selection results in

Question1 of 20
Homology is evidence of ______.
A. directional selection
B. convergent evolution
C. genetic drift
D. common ancestry
2 of 20
Which one of the following statements is true?
A. Natural selection works on non-heritable traits.
B. Natural selection works on variation already present in a population.
C. Individuals evolve through natural selection.
D. Organisms evolve structures that they need.
3 of 20
Natural selection results in ______.
A. increased genetic variation
B. offspring better adapted to a future environment
C. a decrease in the size of a population
D. offspring adapted to their current environment
4 of 20
Who believed in species change by passing acquired characteristics on to offspring?
A. Wallace
B. Mendel
C. Lamarck
D. Darwin
5 of 20
Which one of the following will prevent significant genetic drift?
A. Gene flow is absent.
B. The population size is large.
C. There is genetic variation.
D. Variation in a particular trait is heritable.
6 of 20
Which of these types of Galapagos species most influenced Darwin to develop the theory of species change by natural selection?
A. Goats
B. Reptiles
C. Small birds
D. Cacti
7 of 20
All of the alleles of all of the genes within a population make up that population’s ______.
A. genotype
B. heterozygosity
C. gene pool
D. gene flow
8 of 20
A small population of deer is introduced to an island. All the males have 11-13 points on their antlers. After several generations, if all males have 12 point antlers, this is due to
A. disruptive selection.
B. stabilizing selection.
C. directional selection.
D. bottleneck effect.
9 of 20
Two nearby populations, in which there is some movement of individuals between the populations, are an example of
A. gene flow.
B. disruptive selection.
C. genetic drift.
D. bottleneck effect.
10 of 20
Evidence which supports the theory of evolution is found in studies of
A. embryos.
B. biochemistry.
C. fossils.
D. All of the above.
11 of 20
Which of the following is an example of sexual selection?
A. Peahens choose to mate with peacocks that have the most beautiful tails.
B. Bacteria evolve resistance to antibiotics.
C. Sexual recombination occurs during meiosis.
D. Cheetahs experienced a population bottleneck.
12 of 20
The publication date of Darwin’s The Origin of Species was
A. 1809.
B. 1830.
C. 1869.
D. 1859.
13 of 20
Imagine a population of tree frogs in South America whose habitat has been reduced to the point where only 25 frogs survive. This is an example of
A. founder effect.
B. bottleneck effect.
C. genetic drift.
D. All of the above.
14 of 20
Homologous structures, such as a bat wing and whale flipper
A. are similar externally but have different basic structures and were probably not derived from a common ancestor.
B. are the result of pairs of chromosomes that are identical in bats and whales.
C. have the same underlying structure due to inheritance from a common ancestor.
D. are structures that did not develop in response to natural selection.
15 of 20
Which of the following is an example of directional selection?
A. The birth weight at which newborn humans are most likely to survive and the average weight of newborn humans are about the same.
B. There is an increase in antibiotic-resistant strains of bacteria.
C. Garter snakes with different coloration patterns behave differently when threatened.
D. A catastrophe wipes out nearly 99% of a population.
16 of 20
A small population of deer is introduced to an island. All the males have 11-13 points on their antlers. After several generations, if most males have antlers with 20 points, this is the result of
A. the founder effect.
B. stabilizing selection.
C. disruptive selection.
D. directional selection.
17 of 20
Darwin and Lamarck both realized that most species produce many more offspring than is necessary to maintain a constant population. What is the fate of the excess individuals?
A. Evolution kills them off.
B. They evolve to take advantage of natural resources.
C. The more favorable forms survive and reproduce, while the others do not.
D. They mutate and then are able to adapt to new environments.
18 of 20
Genetic drift results in a change in gene frequencies because
A. the population size is so small that chance occurrences can alter gene frequencies.
B. reproduction is non-random within the population.
C. the population has not yet stabilized.
D. the population is so large that natural selection has little noticeable effect.
19 of 20
Which of the following males in a given population would be considered the most fit in an evolutionary sense? One that produced
A. 1,000 offspring, of which 100 survived but 99 did not reproduce.
B. two offspring, both of which survived and produced offspring of their own.
C. 10 offspring, of which 10 survived, but nine did not reproduce.
D. 100 offspring of which 10 survived but nine did not reproduce.
20 of 20
While on the Beagle, Darwin was influenced by a book by Charles Lyell that suggested that Earth was ______ and sculpted by geologic processes that ______ .
A. old; continue
B. old; no longer occur
C. young; continue
D. young; no longer occur