The founder effect and the bottleneck effect are cases in which a small population is formed from a larger population. These “sampled” populations often do not represent the genetic diversity of the original population, and their small size means they may experience strong drift for generations.
Explanation:
Bottlenecks and founder effects. Genetic drift can cause big losses of genetic variation for small populations. Population bottlenecks occur when a population's size is reduced for at least one generation. ... A founder effect occurs when a new colony is started by a few members of the original population.
A bottleneck event severely reduces the fraction of a species able to pass on their genes to offspring. Any once rare recessive traits present in the surviving breeding population are passed to a larger fraction of the total population of offspring, thereby enriching those recessive traits in the total gene pool.
YY là kiểu gen trội đồng hợp tử (2 alen Y). Kiểu hình của kiểu gen này có màu hạt vàng. Yy là kiểu gen dị hợp tử (một alen trội, một alen lặn). Kiểu hình của kiểu gen này có màu hạt vàng.