Chapter 3
You are reading a magazine article about the Galapagos islands and come across information about Darwin's work there. Which of the following impressed Darwin about the finches on the islands?
a. Certain species of finches had unusual reproductive behaviors
b. Each species of finch had a distinct beak that was well suited to the finch's diet.
c. Some finches changed during their lifetime to better suit their environment.
d. Galapagos finches were able to survive despite the conditions on the island.
b. Each species of finch had a distinct beak that was well suited to the finch's diet.
You are studying a population of fish. You notice that some of the males are plain silver, while other males have bright colors. The females prefer to mate with bright males. As a result, bright males leave an average of 3.5 offspring each. Dull males leave an average of 2 offspring each.
How do you predict this fish population will evolve?
a. The population will not evolve.
b. Dull males will become more common in the population.
c. Bright males will become more common in the population.
d. Dull and bright males will be equally common in the population.
c. Bright males will become more common in the population.
Kai finds an amazing caterpillar in his backyard. The caterpillar has markings on it's skin that frightens predators because it looks like a snake. Suppose that a mutation in one of the caterpillar's genes causes the caterpillar's offspring even more closely.
How will this mutation become more or less common in the population?
A. This mutation makes the caterpillar more likely to survive and reproduce and is likely to randomly fluctuate in the caterpillar population.
B. This mutation makes the caterpillar less likely to survive and reproduce and is likely to become less common in the caterpillar population.
C. This mutation makes the caterpillar more likely to survive and reproduce and is likely to become more common in the caterpillar population.
D. This mutation does not affect the caterpillar's probability of surviving and reproducing and is likely to randomly fluctuate in the caterpillar population.
C. This mutation makes the caterpillar more likely to survive and reproduce and is likely to become more common in the caterpillar population.
Tania has learned that dolphins are actually mammals, even though at first glance they look a lot like fish. She has read that dolphins look somewhat like fish because of convergent evolution. Tania thinks that this is amazing, and now she wants to write a report on convergent evolution. She needs to think of another example of convergent evolution that she can talk about in her report.
Which of the following is also an example of convergent evolution?
A. Dogs and lions both have fur.
B. Eagles and flies both have wings.
C. Mammals and birds both have lungs.
D. Crayfish and spiders both have a segmented body.
A. Dogs and lions both have fur.
Darwin was working on his ideas about how living things change over time when he read about the economist Thomas Malthus. Malthus argued that there was never enough food to keep up with human population growth. As a result, humans would always suffer from famine and misery.
Which of the following ideas from Darwin was inspired by Malthus's writing?
a. Fossil species change over time to produce modern species.
b. Large changes result from many small changes built up over time.
c. Organisms change during their lifetime to become better suited to living in their environment and pass these traits to their offspring.d. All living things are in a constant "struggle for existence" because there are not enough resources for all to survive and reproduce.
d. All living things are in a constant "struggle for existence" because there are not enough resources for all to survive and reproduce.
You are studying a population of fish where individuals come in two different colors. Some fish are silver and others are gold. You wonder if predators are more likely to eat one type of fish. You study the fish population for several months and determine that 15% of silver fish are eaten by predators, while 23% of gold fish are eaten by predators.
How do you predict this fish population will evolve?
a. The population will not evolve.
b. Gold fish will become more common in the population.
c. Silver fish will become more common in the population.
d. Silver and gold fish will become equally common in the population.
c. Silver fish will become more common in the population.
Marco's little brother is watching a TV program about the gene that causes the genetic disease hemophilia. People with this disease cannot make a protein that is needed for blood to clot. After a few minutes, he turns to Marco and asks, "what exactly is a gene, anyway?"
Which of the following best describes a gene?
a. A gene is a random change to an organism's DNA.b. A gene is a structure in a cell that contains the cell's chromosomes.
c. A gene is made of DNA and contains the instructions for building proteins.
d. A gene is a protein that makes up an organism's structure and helps it function.
c. A gene is made of DNA and contains the instructions for building proteins.
During an experiment, a scientist released dark moths and light months into a polluted and a non-polluted environment. Which of the following accurately describes a pattern in the moth population?
a. In polluted environments, dark moths survived better than light moths.
b. In polluted environments, light moths survived better than dark moths.
c. In unpolluted environments, dark moths survived better than light moths.
d. In unpolluted environments, the color of the moth had no impact on the moth's survival.
a. In polluted environments, dark moths survived better than light moths.
A peacock's feathers are an example of what kind of selection? Explain.
Sexual selection. The colorful feathers make them more attractive to the females of the species.
Mosquitoes spread a lot of diseases that are dangerous to humans. People sometimes use insecticides, chemicals that kill insects, to control mosquito populations. Why do mosquitoes evolve resistance to insecticides over time?
Mosquitoes evolve resistance to insecticides because when insecticides are used on a population, only the mosquitoes that have resistance to the insecticides will survive to reproduce and they will pass these traits on to the next generation.