natural selection
What is natural selection?
What is a mutation?
A change in an organisms DNA sequence
What is genetic drift?
Random changes in allele frequencies wihtin a population
What is gene flow?
The movement of alleles between populations through migration and reproduction
True or Flase:
Individual organisms evolve during their lifetime
False.
Populations evolve across generations
A population of rabbits lives in a snowy environment. Which rabbits are more likely to survive: white or brown?
White rabbits because their fur provides camouflage
Can mutations be beneficial, harmful, or neutral?
Yes, mutations can have any of these effects
Does genetic drift have a greater effect on small or large populations?
Small populations
A bird moves to another population and successfully reproduces. What evolutionary process occurs?
Gene flow
True or False:
Humans evolved from modern monkeys.
False
Humans and modern monkeys share common ancestors
Why do bacteria become resistant to antibiotics?
Resistant bacteria survive antibiotic treatment and reproduce, increasing resistance in the population
A mutation produces thicker fur in an animal living in a cold climate. How might this affect survival?
It may improve survival and reproduction if thicker fur helps the animal stay warm.
A storm randomly kills most beetles in a population. What evolutionary event could this represent?
The bottleneck effect
How can gene flow affect genetic diversity?
It can introduce new alleles and increase genetic diversity within a population
True or False
Evolution always makes organisms stronger or better
False
Evolution does not have a predetermined goal
Plants with deeper roots that can reach water
Why are mutations important to evolution?
They create new genetic variations that can be passed to offspring.
A few birds travel to an isolated island and establish a new population. What is this called?
The founder effect
Two populations of wolves begin breeding after a wildlife corridor connects their habitats. What happens?
Gene flow occurs, making the populations more genetically similar over time
True or False
All mutations are harmful
False
Mutations can be beneficial, harmful, or neutral
How does natural selection cause evolution over generations?
Advantageous inherited traits become more common because organisms with those traits reproduce more successfully
Do organisms develop mutations because they need to survive?
No. Mutations do not occur because an organism needs them. Natural selection can favor beneficial mutations afterward.
What might happen if gene flow between two populations stops for many generations?
The populations may become genetically different and could eventually evolve into separate species.
True or False
Natural selection and evolution are exactly the same thing
False
Natural selection is one mechanism of evolution