Evolution
Population's DNA change overtime
Gene Pool
All the DNA from a population
Ways to chance a gene pool
Immigration, Emigration, Birth, Death
Allele Frequency
Percent of an allele in a population
What results in Evolution
Any process that changes or disrupts allele frequencies
Two ways to create Evolution
Natural selection, genetic drift
Natural Selection
The organism that is better adapted survives.
Genetic Drift
Chance events that change the population
Species
individuals in a population that can make and produce fertile offspring.
Speciation
The process to make a new species
Geographical Isolation
Physical barrier that prevents part of a population from mating.
Temporal Isolation
Individuals in a population that are active at different times
Reproduction Isolation
The physical act of reproduction is impossible
Behavioral Isolation
individuals in a population may have different behaviors that prevent mating.
Polyploidy
a mistake during meiosis that leads to additional chromosomes present
Fertile Hybrid
occasionally, two different species mate to produce a fertile hybrid
Embryology
By comparing the similarities between between the different embryos, it is thought that many organisms share a common ancestor
Vestigial Structures
Structures in current organisms that have no function but are leftovers from ancestors. You can see how organisms change overtime
Molecular (DNA) Evidence
By comparing DNA between species, you can see similar proteins and sequences that they share. The more similarities, the more recently they likely share a common ancestor.
Homologous Structure
Features in organisms that are similar in structure (having two eyes, one mouth, four limbs, etc.) But may appear different physically between organisms and may have different functions (shows there was a common ancestor)
Analogous Structure
Animals in similar environment will usually evolve very similar adaptations/structures independently of one another (ex. Many different types of species in the snow will eventually evolve white coats independently of one another.
Coevolution
Different species who interact so closely that a change in one species often results in a change in the other.
Convergent Evolution
two or more unrelated species evolving similar characteristics due to similar characteristics
Divergent Evolution
closely related species evolving in different directions due to different selective pressures.