Natural and artifical selection Flashcards
Define evolution.
Evolution is the process by which species of organisms change over time through variations in traits and the passing of those traits to the next generation.
What is Charles Darwin’s theory of evolution by natural selection?
Darwin’s theory states that organisms with traits better suited to their environment are more likely to survive and reproduce, passing those advantageous traits to their offspring, leading to gradual changes in species over time.
How do fossils provide evidence for evolution?
Fossils show how species have changed over time, revealing the existence of species that are now extinct and illustrating gradual changes in traits across different geological periods.
How does the case of the peppered moth support the theory of natural selection?
During the Industrial Revolution, the darker form of the peppered moth became more common due to increased pollution, which made the light-colored moths more visible to predators. This is an example of natural selection favoring the moths that were better camouflaged in their environment.
What is the difference between natural selection and artificial selection?
Natural selection occurs when environmental pressures determine which organisms survive and reproduce, while artificial selection involves humans selecting specific traits in organisms to breed for desirable characteristics.
Can you give an example of artificial selection?
One example of artificial selection is the breeding of dogs. Humans have bred dogs for specific traits, like size, coat type, or behavior, resulting in a wide variety of dog breeds with distinct characteristics.
What is an adaptation in the context of evolution?
An adaptation is a characteristic or trait that improves an organism’s chances of survival and reproduction in its environment.
What does the phrase “survival of the fittest” mean?
“Survival of the fittest” means that individuals with traits that are best suited to their environment are more likely to survive and reproduce, passing those traits on to the next generation.
How does antibiotic resistance demonstrate natural selection in bacteria?
Bacteria that have mutations allowing them to resist antibiotics are more likely to survive and reproduce when exposed to antibiotics, leading to an increase in the number of resistant bacteria over time.
Why is genetic variation important for natural selection?
Genetic variation provides the raw material for natural selection, as it offers a range of traits that may be advantageous in a particular environment, increasing the likelihood of survival and reproduction.
