Evolution Flashcards
What is evolution
The change in the frequency of traits or allows over generations
What does evolution require
A variation in traits
How are variations in traits created
Through mutation
What is an agent of evolution
A factor contributing to the change in frequency of a Liles overtime
What are the four agents of evolution
Mutation natural selection genetic drift and migration
What is natural selection
The environment force determining whether a trait is advantageous or deleterious
Traits that are favoured by natural selection increase in what overtime
Frequency
Traits that are less favourable or harmful blank in frequency overtime
Decrease
What is genetic drift
The change in frequency of an allowed due to small population size
Genetic drift affects traits in what way
Randomly
What can genetic drift lead to
Genetic erosion
What is inbreeding
The mating of genetically similar individuals
What is migration
The change in the frequency of an allowed due to individuals entering and exiting a population
What’s the difference between immigration and emigration
Immigration=into a population
Emigration=out of a population
What can migration increase
Genetic variation
What are patterns of evolution
Theories describing how rapidly and consistently evolution occurs over time
What is gradualism
The theory that revolutionary change is constant and slow
what is punctured equilibrium
The theory that revolutionary change occurs in rapid bursts following by long periods of no change
Evolution occurs gradually when there is what
A disturbance
What is a disturbance
Any event that eliminates a significant number of species from an ecosystem
What are the three examples of disturbances
Global warming super volcanos and astroid impacts
Following a disturbance what opens up in the ecosystem
Niches
What is adaptive radiation
A sudden burst of speciation
How many mass extinctions were there
5
How do we get new species
When the low frequency of a population become so extreme that individuals are no longer able to reproduce with other populations
What is a species
A group of genetically related organisms that are able to produce viable offspring
What is speciation
The process of new species emerging due to evolutionarily forces
