What is Evolution Flashcards
Define Evolution
a change in a population over many generations, not in the characteristics of one individual over a single lifetime.
Define Natural Selection
a process that produces and maintains adaptive traits within populations.
Define MICROevolution
when genetic makeup of the entire population changed over many generations
Define MACROevolution
when major changes in a lineage include the formation of new species.
What are the steps of natural selection?
A mutation occurs in the species, selection occurs in one of the species types, then adaptation of that type over many generations.
Define a population
Members of the same species in a given area that will breed with one another
Define selection
when some genetic types in a population reproduce more than others in a given environment.
Define sexual selection
Selection based on preference due to characteristics displayed by the opposite sex
Artificial selection
Where humans deliberately breed certain traits into animals and/or plants
Define gene flow
When new alleles enter a gene pool due to the carriers having migrated from one place to another
Describe genetic drift
When a random event changes the frequency of an allele or alleles in a gene pool
Artificial selection
Where humans deliberately breed certain traits into animals and/or plants
What are the two processes that can add new alleles to a gene pool?
Mutation and gene flow.
Describe genetic drift
When a random event changes the frequency of an allele or alleles in a gene pool
What is the Founder Effect?
A form of genetic drift where a small group leave a population and start their own gene pool elsewhere
What happens if you have gene flow from a mix of many different populations?
The offspring will be mostly Heterozygous
At what level does microevolution occur?
The population level
At what level does macroevolution occur?
At the species level.
What is a speciation event?
When a new species forms.
What is a clade?
A group of species that all come from the same branch.
What is the significance of homologous features?
They indicate relatedness or shared ancestry among species.
How do you interpret cladograms?
Everything organism listed after the trait possesses that trait.
Define a species…
A group of organisms that can reproduce viable offspring, then migrate and reproduce again with new members of that type of group
Define Homologous features…
Features that different types of organisms have, demonstrating they all have a common ancestor
Define Analogous features…
Features that different types of organisms develop due to their environments, not bc of a shared ancestor
What provides the most accurate info for determining lineage aka homology?
DNA/RNA
What data provide the best way to compare a species?
DNA data bc the changes in the DNA overtime provide the most comparison data about the different species.
REVIEW
Review the Macroevolution personal practice quiz
