Darwin
Darwin's published work was called __________.
The origin of species
What are vestigial traits? Provide an example.
Traits a modern species has that came from an ancestor, but they no longer have use for it.
Example: A snake or whale pelvis
What defines a species? What is speciation?
A group of the same organisms that can breed with each other and produce fertile offspring. Speciation is the word for the formation of a new species.
Define "population"
A group of the same species living in one area, living separate than other groups.
What is the difference between microevolution and macroevolution?
Microevolution refers to small changes over short periods of time within a population. Macroevolution refers to larger changes over a much longer time scale
Darwin's proposed theory of evolution is supported by the mechanism of ______________. This mechanism works directly on:(A, b, or c)
a. phenotypes
b. genes
c. mutations
Natural selection
Phenotypes (a)
Define homologous traits and give an example.
Traits that are similar in the structure, but different in the function
Ex: Cat paw, human arm, whale fin
What is genetic drift? How does it affect small/large populations?
Genetic drift describes random chance events that change the gene pool of a population.
Small populations are greatly affected by this, resulting in recessive traits accumulating. Large populations are not as effected.
Explain the concept of genetic equilibrium and its significance in evolution.
Genetic equilibrium is the term that describes the state of a population where the frequency of alleles remains constant from generation to generation. This is significant because it means there is no change in the population and therefore no evolution. It is the basis for determining if a population is evolving and by how much and in what way.
Explain the distinction between artificial selection and natural selection.
Natural selection occurs naturally, while artificial selection is a deliberate process that humans control. In both cases, organisms with favorable traits are more likely to survive and reproduce.
The two species that Darwin notably studied at the Galapagos islands that contributed to his theory of evolution. Describe what he noticed about each.
Tortoises: They had different lengths of necks and shell shapes due to predators and diet
Finches: Different beak shapes in different niches. Each island had different finches.
What are analogous traits? Give an example.
Traits different in structure but similar in function.
Ex: Wing of bat and butterfly
Differentiate between founder effect and bottleneck effect in evolution.
Founder: A small group from the main population breaks off and becomes isolated
Bottleneck: A destructive event destroys a large portion of a population, leaving few individuals behind
Both result in a major change in the gene pool and possible inbreeding.
How do heritable normal differences arise in a population? How do abnormal heritable differences arise?
1. Gene shuffling in gametes (crossing over or the other normal processes that occur to create genetic variation)
2. Mutation
Describe Allopatric vs sympatric isolation. (hint: You must give at least 2 different types of sympatric for full points)
Allopatric: Geographical isolation
Sympatric: Isolation without being physically separated. Includes behavioral, temporal, reproductive.
*All of these (geographic, behavior, temporal) are considered a form of reproductive isolation.
What are the 3 kinds of adaptations?
Behavioral (actions)
Structural (morphology)
Physiological (internal)
Explain the concept of reciprocal traits in evolutionary biology.
Traits in two species that evolve together and allow them to interact more.
May include answers about the red queen hypothesis, an example such as a hummingbird and flower and more.
Compare coevolution, divergent, and convergent evolution.
Co: Reciprocal evolution at the same time
Divergent: Common ancestor becomes many species
Convergent: Species from different ancestors start to have similar traits in response to similar environments
If 75 out of 100 (3/4) mice in a certain population has the allele for brown hair, what is the relative frequency?
75%
What is punctuated equilibrium and how does it contrast with gradual evolution?
Punctuated: proposes evolution occurs in bursts of rapid change followed by long periods of stability. Almost "jump-like."
gradual: suggests that evolutionary changes happen slowly and consistently over time, with no distinct periods of rapid change. A smooth process.
Describe the steps that would've led to the many species of Darwin's finches in the correct order. (i.e. what is the correct steps the finches had to take from beginning to end)
The finches become behaviorally isolated
The gene pool changees
Evolution continues
The founders arrive
The finches become geographically isolated
Founders arrive
Geographic isolation
Gene pool changes
behavioral isolation
continued evoluion
Explain why the statement "humans evolved from monkeys" is incorrect.
Humans and monkeys are both primates, but they share a common ancestor that lived long ago, not a direct evolutionary path where one evolved into the other.
Think of evolution as a branching tree, with different species diverging from common ancestors, not a linear progression where one species directly transforms into another.
Two species of fruit flies whose ranges overlap have different periods of mating activity. Drosophila persimilis breeds early in the morning, while Drosophila pseudoobsura breeds in the afternoon. Identify the kind of isolation occurring.
Temporal Isolation
List the five requirements for a population to be in Hardy-Weinberg equilibrium.
no mutation, random mating, no gene flow (migration), large population size, and no natural selection
Robins typically lay four eggs. Four eggs allow the offspring to be well fed, whereas larger clutches may result in malnourished chicks that have a lower chance of survival. Fewer than four eggs per clutch may result in no surviving offspring if the eggs are preyed upon. Which pattern of natural selection most likely acts to keep four eggs the most common clutch size?
Stabilizing selection