vocab
evolution
the process of biological change in population over time that makes decendants genetically different from their ancestors
adaptation
a feature that allows an organism to better survive in its enviorment
genetic equalibrium
when there are no changes in the allele frequency in a population over time
explain what is meant by the phrase "individuals don't evolve, populations do"
Mutations in individuals are the original source of new alleles in a population's pool of genetic resources
Microevolution
evolution can happen on a small scale affecting a single population
gene pool
the combined alleles of all individuals in a population
describe at least 3 mechanisms of microevolution
Natural Selection: animals more fit for their environment will survive and reproduce more offspring
Genetic drift: results in a loss of variation
Gene flow: results in an increase of variation
macroevolution
can happen on a large scale affecting change in species across populations
genetic drift
random change in the frequency of alleles in a population overtime
explain the principles of natural selection
over production of offspring: lots of offspring and limited resources so there is competition of those resources
Variation: different physical traits
Adaptation: a feature that allows that organism to survive better
Descent with Modification: change in gene frequency
list 5 conditions that must be met for evolution to not occur
1. population is large
2. must be a random thing
3. no migration
4. no mutations
5. no natural selection
Natural Selection
organisms with the "best" traits(adaptations) will live longer and reproduce more than others, causing changes in the population overtime by acting on traits that are heritable
gene flow
movement of genes in/out of a population
explain how diversity within a species has resulted in an increase in fitness
more diverse, less likely the whole species will be eliminated
fitness
how well you can survive in your environment
sexual selection
the selection of traits that aren't necessarily good for survival fitness, but without them you can't pass on your genes at all because you can't reproduce
list the different factors the contribute to genetic variation and explain which is considered the "ultimate" source
Random mutations *ultimate source*
crossing over
migration