Evolutionary Connections
Evolution is the result of
Natural selection and Genetic Drift
Evolution can only happen to
A population over time
When a small segment of a population splits off or becomes isolated from the original population and there is a change in allele frequencies we call it the
Founder effect
What does “the fittest” mean in an evolutionary sense?
The most reproductively successful
Two or more species evolve in response to changes in each other
Coevolution
A species that branched apart and gave rise to different species but is itself no longer alive today.
Common ancestors
The study of where organisms live
Biogeography
When natural disasters change the allele frequency of a population we call it the
Bottleneck effect
Increased number of toe pads to increase grip among Anolis lizards that live in trees is an example of
Variable characteristics
An adaptation
An ecomorph
One extreme phenotype is favored by natural selection
Directional selection
The ability to survive and produce fertile offspring
Biological fitness
These are characteristics that improve the fitness of organisms
Adaptations
A type of evolution that results in new species
Macroevolution
Two species evolve similar traits and structures to survive in the same environment
convergent evolution
Closely related species evolve toward two different phenotypes
Divergent evolution
Phylogenetic trees are based on these three things
DNA evidence
Fossil evidence
Physical characteristics
An adaptation that is common among organisms that live in a particular environment
Ecomorph
A type of evolution that happens within a species ex. Leopard frog populations begin to turn more green overtime.
Microevolution
What is the benefit of genetic variation?
Increases a population’s chance to survive a changing environment.
Different species evolving toward a similar environment
Convergent evolution
Phylogenetic trees show
Evolutionary history or common ancestors
How is an ecomorph different from a species
Ecomorphs are based on best fit characteristics in an environment, while a species is based on successful reproduction.
A random change in allele frequencies that occurs in small populations that is not due to natural selection.
Genetic drift
The observable change in allele frequencies
Microevolution
How long does it take evolution to happen?
Anywhere from a few days with bacteria to a few years if selection pressures are strong all the way to hundreds of millions of years if selection pressures are weak.