Genetic drift is an evolutionary process caused by random events that change the frequency of a gene variant (allele) in a population.
At the beginning of the game, there are five worms of different colors. During each generation, feed the worms by clicking the Feed the worms button until all five pieces of food are distributed at random among the five worms.
The goal of the game is to repeat the process until only one color of worm survives.
These worms are planaria. A planarian is one of many non-parasitic flatworms of the Turbellaria class.
A population bottleneck is an event that significantly reduces the size of a population for at least one generation. The bottleneck may be caused by various events that result in the deaths of organisms, such as severe pandemics, environmental disasters that reduce available resources, the hunting of a species close to the point of extinction, or habitat destruction. Genetic drift acts more quickly to reduce genetic variation in small populations, even if the bottleneck doesn't last for very many generations.
The founder effect refers to the reduced genetic diversity that results when a population is descended from a small number of colonizing ancestors. When a new colony is started by a few members of a larger original population, the colony may have reduced genetic variation and a non-random sample of the genes in the original population.