While Darwin understood that many traits could be inherited, he did not know about genes.

What you'll learn in this topic

We now know that genes underlie the phenotypic variation that's seen in populations.

• The genotypes that underlie phenotypic variation in a population
• How to predict the fitness of individuals with a particular genotype given a selective pressure

Your task is to play the game "Fitness Fever."

Your task will be to select individuals in three different populations whose genes make them more fit or less fit in their environment.