Evolution - Notes Name:

What is Evolution? / The central idea of evolution is that life has a history. The living things on Earth have ______, and that the different species on Earth today share common ancestors.
Over a great period of time evolution can result in ______.
Speciation - The formation of a new ______
How do we know evolution has occurred? / ______- Millions of organisms that lived in the past have gone extinct. We know of their existence from fossils or rarely from frozen specimens.
______Species - There are many organisms that are different species, but are obviously very closely related. Example: Cats
What makes evolution possible? / ______Variation makes evolution possible- If a population was 100% the same… the processes that cause evolution would have NO effect because the genetic make-up would never change.
Evolution only occurs when there is a change in ______within a population over time.

What are the processes that cause a change in the gene frequencies of a population?
/







Does evolution ever stop? / Hardy-Weinberg equilibrium describes ______that are not evolving.
Genotype frequencies stay the same and evolution ______if five conditions are met.
  1. ______genetic drift; population remains very large
  2. ______emigration or immigration: no gene flow
  3. ______mutations: no new alleles added to gene pool
  4. ______sexual selection; Random mating occurs
  5. ______natural selection: all traits aid equally in survival
In nature, populations are expected to evolve because a population can’t maintain ______forever.
–Population numbers will always be threatened by different factors
–Individual organisms will continue to migrate
–New genetic mutations occur frequently
–Species select mates; random mating rarely occurs
–The environment has changed on Earth and continues to change
Understanding Evolution / Although evolution cannot be seen on the small scale of ______, the works of evolution are occurring all the time in ______.
These processes are what contribute to the evolutionary changes between all species.
"One obstacle to understanding evolution is the common misconception that individual organisms evolve. It is the ______, not its individuals, that evolves, as some heritable variation becomes more common at the expense of others."
Icons of Evolution /
  1. Who came up with the theory of natural selection?
  1. What organisms did he study to develop this theory?
  1. What is the copy error called that causes genetic differences?
  1. When will a mutation be passed on to its offspring?
  1. Why do female peacocks prefer brighter attractive male peacocks?
  1. Natural selection is not just about surviving, its also about ….
  1. A group of individuals that are able to interbreed are called ______and belong in the same gene pool.
  1. Explain two examples of how speciation can occur:
1.
2.