Unit 7: Evolution Flashcards
Who proposed the idea that organisms on earth have the characteristics they do because they evolved from other organisms?
Charles Darwin
What was the most influential area of Darwin’s voyage around the world?
The Galapagos Islands
What book did Darwin write, outlining his theory of evolution?
The Origin of Species
What where Darwin’s two major theories?
Natural Selection, and Descent with Modification
What do Darwin’s theories explain?
A) The pattern of similarities and differences among organisms
B) The mechanism of how things evolve
What things influenced the development of Darwin’s theories?
A) The voyage of the Beagle
B) Charles Lyell’s principles of geology
C) Malfous’ essay on population and resources
D) Questions from Alfred Russel Wallace, prompting Darwin to publish
What is it called when traits are selected against/for over time in nature?
Natural Selection
What are the four conditions necessary for natural selection to occur?
A) Variations in the population
B) Heritability
C) Change over time
D) Reproductive Advantage
IF populations produce more offspring than can survive, AND variation exists among the population, AND survival and/or reproduction are not random, then….
The population must evolve.
What conditions must exist for evolution to occur?
A) Populations produce more offspring then can survive
B) There is variation in the population
C) Survival and/or reproduction are not random
What is evolution?
Changes in allele frequency of a population’s gene pool, leading to changes in population over generations
What is the Hardy-Weinberg Equilibrium?
A hypothetical situation where allele frequencies remain constant.
What are the two equations for Hardy-Weinburg?
A) p + q = 1
B) p^2 + 2pq + q^2 = 1
What does p^2 mean in Hardy-Weinburg?
The percentage of homozygous dominant individuals in the population.
What does q^2 mean in Hardy-Weinburg?
The percentage of homozygous recessive individuals in the population.
What does 2pq mean in Hardy-Weinburg?
The percentage of heterozygous individuals in a population
What are the requirements for Hardy-Weinburg Equalibrium?
A) No mutation B) No gene flow C) Very large population size D) Random mating E) No advantage of one phenotype over another
When does Hardy-Weinburg happen in nature?
Never
What are some of the forces that cause evolution?
Natural selection, mutation, gene flow, genetic drift, the founder effect, genetic bottleneck, and non-random mating.
What is Natural Selection?
The idea that organisms that are better adapted to the environment are more likely to survive and reproduce than those not so well adapted to the environment.
What are the three types of natural selection?
Directional, disruptive, and stabilizing natural selection.
What is disruptive natural selection?
Where the intermediate traits were selected against. (think of the peppered moths) Tends to be Mendalian.