Vocabulary
A trait that helps an organism survive and reproduce
Who is credited with the creation of the Theory of Natural Selection?
Charles Darwin
Define Population
A group of individuals of the same species, in the same place at the same time.
What most likely happened to species that are found in the fossil record but have no living members?
Extinction
Darwin studied this bird species and noticed their beaks are different shapes and sizes based on the type of food available to them.
Finches
Define a Species
Give an example of a strong selective force
Disease, Natural Disasters, Extinction events
Explain how fitness influences gene frequency
Gene frequency is the amount of a given gene in a population - if a gene codes for a more fit trait, there will be an increase in the frequency of this gene in a population over time. If a gene codes for an unfit trait, there will be a decrease in this gene's frequency in a population over time.
When looking at two tree frogs, a student noticed that one of the frogs had longer toes than the other. This is an example of
Genetic Variation
This is a type of change in genetic material (DNA) and it can be beneficial, neutral, or harmful: ___________
Mutation
Define Biological Fitness
The ability to survive and reproduce
More fit = more offspring
Less fit = less offspring
Give an example of a Weak Selective Force
Climate Change, Habitat Loss
When species evolve to become so genetically different that they can no longer reproduce with each other and produce fertile offspring.
When individuals at one end of a population's traits have higher fitness than individuals with the opposite or blended traits.
Directive Selection
A change in the gene pool of a population due to chance over time.
Genetic Drift
Define a Selective Pressure
A factor that influences an organism's fitness
The type of evolution where closely related species accumulate differences over time, developing unique traits distinguishing them from their common ancestor.
Divergent Evolution
Explain the difference between Gradualism and Punctuated Equilibrium.
Gradualism is when species evolve very slowly (population changes gradually over time)and punctuated equilibrium is when species evolve rapidly in phases with long pauses of inactivity in between (evolutionary jumps and pauses).
Natural selection that favors intermediate alleles by acting against extreme phenotypes.
Stabilizing Selection
The type of evolution where two species evolve similarly in response to changes in their environments but not because of ancestry.
Convergent Evolution
Provide an example of Natural Selection, Sexual Selection, and Artificial Selection
Answers will vary
Natural Selection - the environment has influence
Sexual Selection - the animal's mate has influence
Artificial Selection - Humans are the influence
What are the 4 principles of Natural Selection?
Explain the difference between absolute dating and relative dating when determining a fossil's age.
Relative dating uses position in the ground or depth to determine age; whereas, absolute dating uses radioactive decay to determine an object's specific age.
Natural Selection that favors individuals at the extremes of the phenotypic range - removing hybrids or middling traits.
Disruptive Selection
Explain the difference betwen Geographic and Reproductive Isolation.
Geographic isolation involves physical separation of populations by barriers (mountains, rivers), preventing interbreeding.
Reproductive isolation refers to mechanisms (behavioral, temporal, genetic) that stop different species from producing fertile offspring, even if they share the same space.