Bird Beak Traits

Question

Scientists collected data about one bird population for five generations. The scientists determined the percentages of birds in the population that had specific beak shape traits, 1-6. The data are represented by the graph shown below.

The line graph titled 'Percentages of Beak Shape Traits in a Population' shows Generation from 0 to 5, in increments of 1, on the horizontal axis. The percentage of population with trait is shown on the vertical axis from 0 to 70, in increments of 10. A solid line labeled 'Beak shape Trait 1' starts at about 15%, gradually falls to 10% in generation 1, slightly rises then falls to below 10% in generation 3, then remains steady through generation 5. A solid line labeled 'Beak Shape Trait 2' starts at about 15%, gradually falls to 10% in generation 2, remains steady at 10% in generation 3, and falls to 0% in Generation 5. A solid line labeled 'Beak Shape Trait 3' starts just below 20%, falls to 10% in Generation 2, rises sharply to about 15% in Generation 3, then falls to slightly above 0% in Generation 5. The dashed line labeled 'Beak Shape Trait 4' starts at 20%, falls to below 10% in Generation 3, and continues to gradually fall to about 5% in Generation 5. Two dashed lines labeled 'Beak Shape Trait 5' and 'Beak Shape Trait 6' start slightly above 20%, rise to above 30% in Generation 1, then gradually rise to about 40% in Generation 3. At generation 3, the beak shape traits diverge. Beak shape trait 5 remains steady at about 40% in Generation 4, then falls to about 35% in Generation 5. Beak Shape Trait 6 sharply rises to 70% in Generation 5.

Multiple Select Question
Which two statements about beak shape between Generation 3 and Generation 5 are supported by the data?

A.
The percentage of birds with Beak Shape Trait 1 remained below 5%.

B.
The percentage of birds with Beak Shape Trait 2 decreased from 15% to 0%.

C.
The percentage of birds with Beak Shape Trait 4 showed a small increase to 10%.

D.
The percentage of birds with Beak Shape Trait 5 steadily increased from 22% to 35%.

E.
The percentage of birds with Beak Shape Trait 6 increased from 40% to 70%.

Answer 1

To determine which statements are supported by the data regarding bird beak shape traits between Generation 3 and Generation 5, we can analyze the changes described in each statement:

A. The percentage of birds with Beak Shape Trait 1 remained below 5%.
Not supported. According to the description, Beak Shape Trait 1 fell below 10% in Generation 3 but did not state it dropped below 5%, and it remained steady through Generation 5.

B. The percentage of birds with Beak Shape Trait 2 decreased from 15% to 0%.
Supported. Beak Shape Trait 2 was at around 15% initially and fell to 0% by Generation 5.

C. The percentage of birds with Beak Shape Trait 4 showed a small increase to 10%.
Not supported. Beak Shape Trait 4 fell from 20% to below 10% by Generation 3 and continued to fall to about 5% in Generation 5, indicating that it did not increase to 10%.

D. The percentage of birds with Beak Shape Trait 5 steadily increased from 22% to 35%.
Not supported. The starting percentage for Beak Shape Trait 5 was stated as slightly above 20%, but it remained steady at about 40% in Generation 4, decreasing to 35% in Generation 5, meaning it did not steadily increase to 35%.

E. The percentage of birds with Beak Shape Trait 6 increased from 40% to 70%.
Supported. Beak Shape Trait 6 was described as having risen significantly to 70% in Generation 5.

Based on this analysis, the two statements that are supported by the data are:

• B. The percentage of birds with Beak Shape Trait 2 decreased from 15% to 0%.
• E. The percentage of birds with Beak Shape Trait 6 increased from 40% to 70%.