Item CA011002: If the DNA of Species X and Species Y is more similar than the DNA of Species X and Species Z, then Species X and Species Y have a more recent common ancestor than Species X and Species Z.
If the DNA of Species X and Species Y is more similar than the DNA of Species X and Species Z, what is a reasonable conclusion about the common ancestors of these three groups?
- Species X and Species Y have a common ancestor, but Species X and Species Z do not.
- Species X and Species Z have a more recent common ancestor than Species X and Species Y.
- Species X and Species Y have a more recent common ancestor than Species X and Species Z.
- Similarities in DNA do not provide information about whether two groups share a common ancestor.
Pre-Test
Answer Choice |
Overall |
Grades |
Gender |
Primary Language |
||||
|---|---|---|---|---|---|---|---|---|
| n = 559 |
6–8 n = 23 |
9–12 n = 499 |
Male n = 221 |
Female n = 300 |
English n = 516 |
Other n = 13 |
||
| A. | Species X and Species Y have a common ancestor, but Species X and Species Z do not. | 23% | 22% | 24% | 26% | 21% | 24% | 23% |
| B. | Species X and Species Z have a more recent common ancestor than Species X and Species Y. | 8% | 4% | 8% | 7% | 8% | 9% | 0% |
| C. | Species X and Species Y have a more recent common ancestor than Species X and Species Z. | 63% | 65% | 62% | 60% | 65% | 62% | 77% |
| D. | Similarities in DNA do not provide information about whether two groups share a common ancestor. | 5% | 9% | 6% | 7% | 5% | 6% | 0% |
Post-Test (Control)
Answer Choice |
Overall |
Grades |
Gender |
Primary Language |
||||
|---|---|---|---|---|---|---|---|---|
| n = 281 |
6–8 n = 18 |
9–12 n = 229 |
Male n = 109 |
Female n = 135 |
English n = 243 |
Other n = 9 |
||
| A. | Species X and Species Y have a common ancestor, but Species X and Species Z do not. | 17% | 22% | 16% | 15% | 19% | 16% | 22% |
| B. | Species X and Species Z have a more recent common ancestor than Species X and Species Y. | 8% | 11% | 7% | 11% | 4% | 7% | 0% |
| C. | Species X and Species Y have a more recent common ancestor than Species X and Species Z. | 72% | 67% | 74% | 74% | 73% | 73% | 78% |
| D. | Similarities in DNA do not provide information about whether two groups share a common ancestor. | 4% | 0% | 3% | 0% | 4% | 3% | 0% |
Post-Test (Treatment)
Answer Choice |
Overall |
Grades |
Gender |
Primary Language |
||||
|---|---|---|---|---|---|---|---|---|
| n = 305 |
6–8 n = 3 |
9–12 n = 280 |
Male n = 139 |
Female n = 150 |
English n = 276 |
Other n = 8 |
||
| A. | Species X and Species Y have a common ancestor, but Species X and Species Z do not. | 8% | 0% | 9% | 11% | 6% | 8% | 25% |
| B. | Species X and Species Z have a more recent common ancestor than Species X and Species Y. | 8% | 0% | 9% | 8% | 9% | 8% | 13% |
| C. | Species X and Species Y have a more recent common ancestor than Species X and Species Z. | 81% | 100% | 79% | 81% | 80% | 80% | 50% |
| D. | Similarities in DNA do not provide information about whether two groups share a common ancestor. | 3% | 0% | 3% | 1% | 5% | 3% | 13% |