Microevolution Flashcards
(24 cards)
Genetic Drift
Chance events can effect allele frequency in new generations
Bottleneck Effect
The elimination and favoring of certain alleles due to disaster
Founder Effect
When few individuals colonize new habitat the new population gene pool won’t represent original population
Gene Flow
Movement of genetic information; Immigration and movement between populations
Evolution
Decent with modification
Sexual selection
Type of natural selection in which traits lead to more sexual reproduction
Sexual dimorphism
Traits related to sexual selection which separate the two sexes of a species
Intersexual selection
Members of one sex are picky about who they mate with
Adaptive radiation
The adaptation of a species into wide variety of modes of life
Natural selection
The pattern of individuals with certain inherited traits reproducing and surviving at higher rates due to their traits
Artificial selection
Traits brought out through human involvement and selective breeding
Homology
Similar bone structures that are related to common ancestory
Analogous structures
Similar bone structures that can’t be related via common ancestor
Hardy-Weinberg Equilibrium
Allele frequencies will not change within a population without a genetic force
Hardy-Weinberg equation can be used…
To determine if a population is evolving using frequencies of different genotypes
Conditions of Hardy-Weinberg equilibrium
- Large population
- No exchange with other populations
- No mutations
- Random mating
- No natural selection
Conditions for traits to evolve
Traits must be
1. Variable
2. Heritable
3. Visible
4. Result in more offspring
Types of evolution
- Directional
- Stabilizing
- Disruptive
Directional evolution
Evolution pushing a population towards one extreme of a trait
Stabilizing evolution
Evolution centering the population on the average of a trait, getting rid of outliers
Disruptive evolution
Evolution that separates the populations into two extremes
Intrasexual selection
Competition between two sexes for mates
Parsimony
The simplest genetic explanation
Clade
Group of organisms with common ancestors
