Evolutionary Biology 1: Adaptive evolution Flashcards
What is microevolution? Conditions necessary for it to occur?
The process of evolution within populations, including adaptive and neutral evolution
- Variation among individuals in lifetime reproductive success, in the number of their offspring that survive to reproduce
- Heritable variation in the trait
Difference between adaptive and neutral evolution?
Its the correlation that makes it adaptive or neutral
- The correlation between a trait and reproductive success is
NATURAL SELECTION
Is natural selection random?
No.
Genetic variation may be random, but natural selection itself is not.
The survival and reproductive success of an individual is directly related to the ways its inherited traits function in the context of its local environment.
Explain an example of natural selection in vitro
RNA added to tube where ATP is coupled to resin
- RNA that does not bind to ATP is discarded
- RNA sequences bound to ATP are amplified are amplified
- > repeat with RNA enriched for ATP-binding function
Explain an example of natural selection in natural populations
Bacteria added to antibiotic growth medium
- Bacteria with resistance genes form colony -> survive and grow on medium
Levels of selection?
Genes
Traits
Organisms
Groups
Four factors that limit selection and why?
- Gene flow: when individuals born in one place or situation breed successfully in another
- It takes time to respond to selection
- Tradeoffs constrain changes in traits connected to other traits with effects on fitness
- Constraints (physical and otherwise)