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How Do We Know Organisms Evolve? - Coggle Diagram
How Do We Know Organisms Evolve?
Five fingers of evolution
Mutations
change in a DNA sequence usually occurring because of errors in replication or repair and is the original source of genetic variation
Gene flow
the flow of genes in and out of a population due to the movement of organisms and their gametes.
non-random mating
organism prefers to mate with others of the same genotype or different genotypes.
Adaptations
natural selection to better adapt to their local environment.
Bottleneck Effect
population’s size is reduced for at least one generation due to an outside factor
Structures
Homologous Structures
They are similar in structure but different in function.
Analogous Structures
different in structure but similar in function.
Vestigal Structures
structures that are useless in an organism but are there because of evolution.
Main Ideas of evolution
Inherited Traits
Inherited traits that improve the odds of survival are more likely to be passed on to the next generation.
Offspings compete
High birth rate results in competition among the species
Variation
Due to their isolation, species in different regions of the world have more variation than others.
Survival of the Fittest
The individuals that survive reproduce, adding their genes to the succeeding generations.
Natural selection
differential survival or reproduction of different genotypes in a population leads to changes in a population’s gene frequencies
Types of evolution
Macroevolution
evolution over geologic time, which leads to a new species. But in order for a new species to arise, there needs to be isolation.
Temporal Isolation - different breeding times lead to reproductive isolation and a new species.
Behavioral Isolation: If a species has a certain behavior in order to reproduce, other species will isolate them, causing macroevolution.
Geographical Isolation - a part of the species gets geographically isolated over time, forming a new species.
Microevolution
small changes mode over time in a species that doesn’t cause speciation.