11.3 Natural Selection Flashcards
What is Modern Synthesis?
The union between genetics and evolution
What is the genetic basis of variation?
Alleles
What are some common misconceptions about natural selection?
- Natural selection only acts on traits present in the population
- The presence of any adaption sometimes means that a slightly less valuable traits must be forgone
- Natural selection results in the fit of an organism to the environment it is currently experiencing, not some future environments
Does natural selection cause new traits to arise?
No
Does natural selection have a goal?
No
Does natural selection result in perfection?
No, it causes organisms to become a better fit to their environment
Directional selection contains?
A change in population traits
What is an example of directional selection?
A population evolving in the direction of a darker color
What does stabilizing selection contain?
A selection for the average units
What is an example of stabilizing selection?
A population stabilizes; nearly all the individuals are the same color
What does diversifying selection contain?
Selection for extremes
What is an example of diversifying selection?
A population diversified into pale variety and dark variety
All new genetic variation comes from?
Mutations
