Lec. 33 - Evolution Flashcards
Explain evolution and the concept of gene frequencies.
Evolution is a change in a species through time. Gene frequencies change over time because they have several variations called alleles, which code for different traits associated with a given characteristic.
Explain how alleles relate to gene pools, frequency, and evolution.
Allele frequency is the rate at which a specific allele appears in a population. The gene pool is the sum of all the alleles at all genes in a population.
Describe the “agents of change” involved in evolution.
The 5 agents of change are mutation, gene flow, genetic drift, non-random mating, and selection.
Compare the theories of evolution between Lamarck and Darwin.
Lamarck and Darwin both agree that evolution is occurring, but they don’t agree on how it is occurring. Lamarck. said that acquired traits could be passed on to offspring. Darwin said that adaptive traits would be the ones passed on to offspring.
Explain the types of selection. (stabilizing, directional, disruptive)
Stabilizing selection favors average individuals, directional selection favors one extreme, and disruptive selection favors either extreme.
Describe divergent and convergent evolution.
Divergent evolution has a common ancestor, so organisms may look/act differently, but they are still related. Convergent evolution does not have a common ancestor, but organisms look/act the same, but they aren’t related.
Explain the evidence for evolution. (fossils, anatomy, embryology, molecular biology)
Fossils are the evidence for evolution because they show preserved remains of animals, plants, and other organisms from the past. They are important because they show that life on earth was once different from what we know today.
