Primary School (K-2)
Elementary School (3-5)
Sometimes the differences in characteristics between individuals of the same species provide advantages in surviving, finding mates, and reproducing.
Middle School (6-8)
Natural selection leads to the predominance of certain traits in a population, and the suppression of others.
In artificial selection, humans have the capacity to influence certain characteristics of organisms by selective breeding. One can choose desired parental traits determined by genes, which are then passed on to offspring.
High School (9-12)
Natural selection occurs only if there is both (1) variation in the genetic information between organisms in a population and (2) variation in the expression of that genetic information—that is, trait variation—that leads to differences in performance among individuals.
The traits that positively affect survival are more likely to be reproduced, and thus are more common in the population.