100%(6)6 out of 6 people found this document helpful
This preview shows page 2 out of 2 pages.
1000 mm/ year. In figure 2, you can see that the allele for shorter beaks significantly increases when there is less rainfall as opposed to when there is a stable amount of rainfall. The allele for long beaks is completely lost in 40 generations because they cannot survive in that environment. Because there is little rainfall, fruits are not able to become ripe and long beaked birds can not eat unripe fruit, but short beaked birds can. In Figure 3 the opposite phenomenon happens. The allele for longer beaks becomes considerably more abundant because there is more rainfall. The abundant amount of rainfall causes more fruits to become ripe and longer beaks are needed to eatripe fruit. The allele for shorter beaks disappears in 30 generations since short beaked birds can not eat ripe fruits.Figure 2.A population of 200 birds with rainfall of 700 mm/year. Long beaked finches are not able to survive therefore the frequency for allele A is completely lost in 40 generations.Figure 3.A population of 200 birds with rainfall of 1300 mm/year. Short beaked finches are not able to survive therefore the frequency for allele B is lost over a few generations.