TABLE 1.
Correct student responses for all interpretation tasks and instruments with comparisons of accuracy across phylogenetic tree styles
| Style | Pre-HW (n = 74) | Post-HW (n = 75) | Unit exam (n = 81) | Final review (n = 72) |
|---|---|---|---|---|
| Most recent common ancestor | ||||
| Diagonal | 73% | 95% | 93% | 92% |
| Bracket | 86% | 95% | 98% | 94% |
| Comparison | p = 0.02 | p = 1.00 | p = 0.22 | p = 0.75 |
| Monophyletic group | ||||
| Diagonal | 54% | 88% | 93% | 92% |
| Bracket | 68% | 91% | 96% | 93% |
| Comparison | p = 0.04 | p = 0.69 | p = 0.38 | p = 1.00 |
| Contemporary descent: answer | ||||
| Diagonal | 73% | 97% | 95% | 94% |
| Bracket | 89% | 100% | 99% | 97% |
| Comparison | p < 0.01 | p = 0.50 | p = 0.38 | p = 0.50 |
| Contemporary descent: reasoning | ||||
| Diagonal | 53% | 81% | 75% | 74% |
| Bracket | 72% | 85% | 80% | 78% |
| Comparison | p < 0.01 | p = 0.51 | p = 0.39 | p = 0.55 |
| Taxa relatedness: answer | ||||
| Diagonal | 11% | 39% | 49% | 46% |
| Bracket | 15% | 55% | 59% | 60% |
| Comparison | p = 0.58 | p = 0.02 | p = 0.04 | p < 0.01 |
| Taxa relatedness: reasoning | ||||
| Diagonal | 5%a | 36%a | 42%a | 40%a |
| Bracket | 8%a | 53%a | 58%a | 50%a |
| Comparison | p = 0.55b | p = 0.02b | p < 0.01b | p = 0.03b |
aMixed reasoning was also found in <10% of student responses.
bp values were derived from a Stuart-Maxwell test due to trichotomous categories (correct, incorrect, or mixed reasoning). All other p values were derived from an exact version of the McNemar test.