Step 7: Determine the Sizes of the Flocks in the Third Generation

Flock X Flock Y Flock Z

Total Pieces of Food Eaten

(from previous page) 147 93 60

Food Percentage*

%

%

%

Simulated Number of Birds in Flock for 3rd Generation**

* Divide each flock's total pieces of food by 300, the total number of pieces of food eaten.

** Multiply the food percentage for each flock by the total number of birds (30).

Competition occurs between species when

Cathy hypothesized that corn would not grow in mud. to test this hypothesis, she took corn kernels and placed 5 in mud, 3 in soil, and 2 in water. to her surprise, the kernels in the mud grew faster than the kernels in the soil. what error might have caused these unexpected results? a. wrong hypothesis b. not enough variables c. undefined control d. too many variables

Which of the following statements is true about the relationship between genetic variation and natural selection? a. genetic variation must be present in a population before natural selection can act on it. b. genetic variation arises in a population as a result of natural selection. c. natural selection can act on a population whether there is genetic variation within the population or not. d. after natural selection acts on a population, the amount of genetic variation in the population always increases.