Lecture 5 Flashcards
Myths: Evolution is Goal Oriented
evolution by natural selection is not goal oriented, adaptations don’t occur because organisms want or need it
Myths: Evolution produces a hierarchy of life
no organism is higher than another, everything evolved from a common ancestor
Myths of Evolution
- goal oriented
- produces a hierarchy
- does not inevitably increase complexity
- animal behaviour is selfless and for the good of the species
- natural selection results in the most optimal phenotype
Fitness Trade-offs
compromise between traits in terms of how those traits are adapted for the environment
Examples of trade offs
- peacock tails
- sickle cell anemia
Genetic Correlation
changing one feature often affects multiple features
Historic Constraints
species evolve from ancestors
Formal Constraints
law of physics
Temporal Constraints
mutation is slow and often the mutations don’t have an effect
Four factors that influence allele frequencies
- Natural Selection
- Genetic Drift: cause allele frequencies to change randomly
- Gene Flow: alleles coming into a population
- Mutation: introduces new alleles
Hardy Weinburg Principle
developed a mathematical model to analyze allele frequencies of individuals in a population