Vocabulary
What word describes a change in an organism’s DNA?
Mutation
What process allows organisms to produce offspring?
Reproduction
Are mutations directed by the environment to help organisms survive?
False
How does a bird’s beak shape help it survive?
Its beak allows it to access and eat specific foods, increasing survival.
Who evolves over time: an individual or a population?
Population
What do we call a trait that increases an organism’s chances of surviving and reproducing?
Adaptation
What term describes when more offspring are produced than the environment can support?
Overproduction
Can an organism pass on traits it develops during its lifetime?
False
When some bacteria survive an antibiotic and reproduce, what does this show about evolution in populations?
Natural selection favors traits that help survival, changing the population over time.
What source provides new genetic material for evolution?
Mutations
What term describes a group of the same species living in the same area at the same time?
Population
What do we call the differences in traits among individuals in a population?
Variation
Can environmental changes shift which traits are considered helpful in a population?
True
How does a rabbit’s fur changing color in winter improve its chances of avoiding predators?
Camouflage helps it blend in, reducing the chance of being caught.
What must happen for a trait to increase in frequency in the next generation?
Organisms with that trait must reproduce
What is the process of passing genetic traits from parents to offspring called?
Inheritance
Why does natural selection act on phenotypes (traits you can see) rather than directly on genotypes (DNA)?
Because the environment “interacts” with expressed traits, and those traits determine survival and reproduction.
Can a trait be considered an adaptation only if it improves survival or reproduction?
True
Why do repeated pesticide treatments lead to a higher number of resistant insects in a population?
Only the resistant individuals survive and reproduce, so the trait becomes more common
Does natural selection create new traits or act on existing ones?
Acts on existing ones
Why is a population, not an individual, considered the smallest unit that can evolve?
Because individuals do not pass on traits they gain during their lifetime; only populations change over generations through reproduction.
How does overproduction lead to competition and influence which traits are passed on?
Limited resources mean not all survive, so those with helpful traits are more likely to reproduce and pass on their traits.
If variation decreases in a population, will the ability of that population to adapt over time likely increase or decrease?
Decrease
How can two populations of the same species living in very different environments develop such different traits that they can no longer interbreed?
Different environmental pressures favor different traits, leading to reproductive isolation and eventually speciation.
Why does natural selection depend on both variation and limited resources to drive evolutionary change?
Variation provides different traits, and limited resources create competition so some traits are favored over others.