Microevolution, Macroevolution, Genetics and Heredity Vocab

Gene Pool

All the alleles present in the population

Allele Frequency

How common an allele is in a population

Microevolution

Small scale changes in allele frequencies

Mutation

Random changes in DNA that create new alleles

Natural Selection

Individuals with certain traits survive/reproduce more

Genetic Drift

Random changes in allele frequencies (stronger in smaller populations)

Gene Flow

Movement of alleles into or out of a population

Bottleneck Effect

Population drops sharply, surviving gene pool is limited

Founder Effect

Small groups starts a new population which causes reduced population

Artificial Selection

Humans intentionally breeding organisms for desirable traits

Nonrandom Mating

When individuals choose mates based on traits

Sexual Selection

Traits that increase mating success

Adaptation

A heritable trait that increases fitness (physical, behavioral, or internal )

Fitness

Reproductive success (how many offspring you leave)

Hardy Weinberg Equilibrium

Allele Frequencies stay constant

Macroevolution

Evolutionary changes above the species level

Speciation

Formation of new species

Reproductive isolation

Barriers to prevent species from interbreeding with other species

Prezygotic Barriers

Prevent mating or fertilization from happening

Postzygotic

Fertilization happens, but issues occur after

Allopatric Speciation

Speciation caused by geographic separation

Sympatric

Speciation that occurs without geographic separation

Adaptive Radiation

Many species evolve form one ancestor

Convergent Evolution

Different species evolve similar traits

Divergent Evolution

Species become more different over time

Co-evolution

Two species evolve in response to each other

Punctuated equilibrium

Species stay the same for long periods, then change quickly in short bursts

Gradualism

Evolution happens slowly through many small changes

Homologous structure

Same structure, different function (common ancestor)

Analogous Structures

Same function, different structures (not related)

Vestigial Structures

Remnants of once useful traits

Character Displacement

When traits diverge in order to reduce competition

Polymorphism

Same species but they look different

Autopolyploidy

Two of the same species mate, its offspring’s cells accidentally double the 2 sets of chromosome into 4. It could still mate.

Allpolyploidy

2 different species mate and create an offspring with chromosomes each from 2 different species causing it to become sterile.

Cladogenesis

One species is split into two or more species

Ecological Species

Species stay separate because natural selection favors traits suited to their environment. Hybrids usually don’t survive, so they don’t affect the species.