Evolution Flashcards
All 5 cards in this deck
What is evolution?
A change in the inherited characteristics of a population over time, through the process of natural selection, which may result in the formation of a new species.
What does the theory of evolution by natural selection state about the origin of species?
All species of living things have evolved from simple life forms that first developed more than three billion years ago.
What are the steps to explain a characteristic by natural selection?
e.g. rabbits living where the climate becomes colder
- Variation: some rabbits have thicker fur than others.
- Those better adapted survive and reproduce: thick-furred rabbits survive the cold and breed.
- The favourable alleles are passed on: thick fur becomes more common in the population.
When have two populations of one species become two new species?
When their phenotypes are so different that they can no longer interbreed to produce fertile offspring.
True or false? An individual organism evolves during its lifetime to become better adapted.
False. Individuals cannot evolve; populations change over many generations as favourable alleles become more common.