Microevolution, speciation and macroevolution Flashcards
What is microevolution?
Microevolution is evolution in a single population
How can microevolution be detected?
through changes in gene frequency over time
What is speciation?
the mechanisms by which new species are formed
What are two types of speciation?
- allopatric speciation
2. sympatric speciation
When does allopatric speciation occurs?
Occurs when a physical barrier divides a population. Barriers to gene flow arise and when population is all one species
What is sympatric speciation?
New species develops when members of a population develop a genetic difference that prevents them from reproducing with members of the original species within the same area
Give an example of sympatric speciation.
herbivorous insects try out a new host plant
What is co-evolution?
Where two or more species affect each other’s evolution
Give an example of co-evolution.
Flowering plants and pollinators and predator/ prey relationships
What are some forces operating in evolution at the molecular level?
- mutations
- control of gene expression
- rate of protein synthesis`
What are some forces operating in evolution at the chromosomal level?
- crossing over
- mutations
- changes in chromosomes
- independent assortment
- recombination
What are some forces operating in evolution at the organism level?
- reproductive success
- selection pressure
- environmental modification of phenotype
- fitness of the phenotype
What are some forces operating in evolution at the species level?
- geographical barriers
- reproductive isolation
- selection pressures
- interspecific competition
What are some forces operating in evolution at the population level?
- genetic drift
- mate selection
- natural selection
- intraspecific competition
- immigration/ emmigration (gene flow)
- population bottlenecks
How is microevolution formed?
It works with organisms that can interbreed with each other and share a gene pool.
