An event that describes the idea of catastrophism
The sudden demise of the dinosaurs, and various other groups, by the impact of a large extraterrestrial body with Earth
the prevailing notion prior to the time of Lyell and Darwin
Earth is a few thousand years old, and populations are unchanging
During a study session about evolution, one of your fellow students remarks, "The giraffe stretched its neck while reaching for higher leaves; its offspring inherited longer necks as a result." What decription is most likely to be helpful in correcting this student's misconception?
Characteristics acquired during an organism's life are generally not passed on through genes.
In the mid-1900s, the Soviet geneticist Lysenko believed that his winter wheat plants, exposed to ever-colder temperatures, would eventually give rise to ever more cold-tolerant winter wheat. Lysenko's attempts in this regard were most in agreement with the ideas of...
In Darwin's thinking, the more closely related two different organisms are, the...
more recently they shared a common ancestor
Natural selection is not based on
individuals adapt to their environments and, thereby, evolve.
Natural selection is based on all of the following
genetic variation exists within populations. the best-adapted individuals tend to leave the most offspring. individuals who survive longer tend to leave more offspring than those who die young. populations tend to produce more individuals than the environment can support.
During drought years on the Galapagos, small, easily eaten seeds become rare, leaving mostly large, hard-cased seeds that only birds with large beaks can eat. If a drought persists for several years, what should one expect to result from natural selection?
More small-beaked birds dying than larger-beaked birds. The offspring produced in subsequent generations have a higher percentage of birds with large beaks.
Today, DDT is largely useless against many insects. Which of these would have been required for this pest eradication effort to be successful in the long run?
None of the individual insects should have possessed genomes that made them resistant to DDT.
Logically, what should have casted the most doubt on the relationships depicted by an evolutionary tree?
Relationships between DNA sequences among the species did not match relationships between skeletal patterns.
Members of two different species possess a similar-looking structure that they use in a similar fashion to perform the same function. Which information would best help distinguish between an explanation based on homology versus one based on convergent evolution?
The two species share many proteins in common, and the nucleotide sequences that code for these proteins are almost identical.
Structures as different as human arms, bat wings, and dolphin flippers contain many of the same bones, these bones having developed from very similar embryonic tissues. How do biologists interpret these similarities?
By proposing that humans, bats, and dolphins share a common ancestor
the smallest unit that natural selection can change?
a population's gene frequency
What is a TRUE statement concerning genetic variation?
It must be present in a population before natural selection can act upon the population
You are studying three populations of birds. Population A has ten birds, of which one is brown (a recessive trait) and nine are red. Population B has 100 birds, of which ten are brown. Population C has 30 birds, and three of them are brown.
In which population would it be LEAST likely would alter the frequency of the brown allele?
You are maintaining a small population of fruit flies in the laboratory by transferring the flies to a new culture bottle after each generation. After several generations, you notice that the viability of the flies has decreased greatly. Recognizing that small population size is likely to be linked to decreased viability, the best way to reverse this trend is to...
cross your flies with flies from another lab
Over time, the movement of people on Earth has steadily increased. This has altered the course of human evolution by increasing the chance of...
Describe an African butterfly species that exists in two strikingly different color patterns within the same population?
diversifying (disruptive) selection
What describes brightly colored peacocks mating more frequently than drab peacocks?
Most Swiss starlings produce four to five eggs in each clutch. Those producing fewer or more than this have reduced fitness. What term best describes this?
Fossil evidence indicates that horses have gradually increased in size over geologic time. What term best describes this?
Mules are relatively long-lived and hardy organisms that cannot, generally speaking, perform successful meiosis. Consequently, what is true statement about mules?
They have a relative evolutionary fitness of zero