Population genetics flashcards #4
To understand how genes work in evolution.
What is the benefit of a mutation for evolution?
It can produce new alleles for a trait.
How did the mutation of the rock pocket mouse benefit him?
Blended in so he lived longer, and was able to reproduce and pass down the new trait.
How do big ears benefit the African Elephant?
It allowed him to stay cool, which allowed him to live longer and pass down the new trait.
Our DNA and genes do not always stay in a population. If an organism travels a long distance to find food. In this process he also finds a mate in the new location. To the new community,this would be an example of
immigration, gene flow(genes flowing into a new community)
After 15 years of living at the California Zoo, the panda at Gao Gao, was returned to China. To california zoo this is an example of
emmigration, gene flow(genes flowing out of the community)
Genetic drift
change in frequencies of alleles due to random event or chance. (genes “drift” away from their normal balance” Always reduces diversity of DNA and therefore traits.
The genetic drift “bottle neck” is best described as
a random event that selects for a specific triat, reducing that trait in the population.
Lobster trap with escape vents to let baby lobsters out, limits the amount of small lobsters stuck in traps where they can be eaten by larger lobsters. Increase of baby lobsters in a population. This is an example of
bottleneck
The genetic drift “ founder effect” is best described as
One breeding is only between certain organism with specific traits.
German shepard Dogs bred with German sherpard Dogs is an example of
founder effect
4 types of genetic drift
bottleneck, founder effect, non-random mating, sexual selection
A damn on a river would prevent fish from going from one place to another, this means they would have to mate with only the fish that are presently in this river. This is an example of
non-random mating
Two deer battle for the female deer, ultimately the bigger, stronger deer wins. This is an example of
sexual selection
What is going to happen to the cricket population, is this tactic continues?
There will be less calling crickets, this can lead to other problems or another evolution to find a mate.
Natural Selection is
after a variation occurs, the organism fits into the environment better, they live longer, and this trait is passed down to its offspring.
If the “average” variation in a population is selected for then this type of selection will occur.
Stabilizing
If the “extreme” variations in a population is selected for then this type of selection will occur
Disruptive
If one extreme variation in a population is selected for then this type of selection will occur
Directional
