Evolution
Evolution and Natural Selection
Similarities and differences in inherited characteristics of organisms alive today or in the past can be used to…
Item CA041002: Similar skeletal features in organisms (chimpanzees and gorillas) indicate a common ancestor.
A class of students is visiting the primate room of a natural history museum. Some of the students are looking at the skeleton of a chimpanzee next to the skeleton of a gorilla.
A sign next to the skeletons reads:
“Do chimpanzees and gorillas share a common ancestor?”
The teacher asks the students to think about that question and then to write an argument to justify their answer. This is what one of the students writes:
Common ancestors are a topic in evolution. Similar skeletal features likely indicate a common ancestor. Chimpanzees and gorillas have similar anatomical features. For example, chimpanzees and gorillas both have opposable thumbs and their ribcages are very similar. Chimpanzees and gorillas may have a common ancestor.
Identify the claim, evidence, and reasoning statement in the student’s argument.
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Claim: Similar skeletal features likely indicate a common ancestor.
Evidence: Chimpanzees and gorillas both have opposable thumbs and similar ribcages.
Reasoning: Chimpanzees and gorillas have similar skeletal features.
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Claim: Similar skeletal features likely indicate a common ancestor.
Evidence: Chimpanzees and gorillas have similar skeletal features.
Reasoning: Chimpanzees and gorillas both have opposable thumbs and similar ribcages.
-
Claim: Chimpanzees and gorillas may have a common ancestor.
Evidence: Similar skeletal features likely indicate a common ancestor.
Reasoning: Chimpanzees and gorillas both have opposable thumbs and similar ribcages.
-
Claim: Chimpanzees and gorillas may have a common ancestor.
Evidence: Chimpanzees and gorillas both have opposable thumbs and similar ribcages.
Reasoning: Similar skeletal features likely indicate a common ancestor.
Pre-Test
Answer Choice |
Overall |
Grades |
Gender |
Primary Language |
||||
|---|---|---|---|---|---|---|---|---|
| n = 580 |
6–8 n = 25 |
9–12 n = 514 |
Male n = 254 |
Female n = 286 |
English n = 526 |
Other n = 13 |
||
| A. |
Claim: Similar skeletal features likely indicate a common ancestor. Evidence: Chimpanzees and gorillas both have opposable thumbs and similar ribcages. Reasoning: Chimpanzees and gorillas have similar skeletal features. |
20% | 28% | 19% | 20% | 18% | 19% | 23% |
| B. |
Claim: Similar skeletal features likely indicate a common ancestor. Evidence: Chimpanzees and gorillas have similar skeletal features. Reasoning: Chimpanzees and gorillas both have opposable thumbs and similar ribcages. |
19% | 16% | 19% | 22% | 16% | 19% | 23% |
| C. |
Claim: Chimpanzees and gorillas may have a common ancestor. Evidence: Similar skeletal features likely indicate a common ancestor. Reasoning: Chimpanzees and gorillas both have opposable thumbs and similar ribcages. |
23% | 28% | 22% | 26% | 20% | 23% | 23% |
| D. |
Claim: Chimpanzees and gorillas may have a common ancestor. Evidence: Chimpanzees and gorillas both have opposable thumbs and similar ribcages. Reasoning: Similar skeletal features likely indicate a common ancestor. |
39% | 28% | 40% | 32% | 46% | 39% | 31% |
Post-Test (Control)
Answer Choice |
Overall |
Grades |
Gender |
Primary Language |
||||
|---|---|---|---|---|---|---|---|---|
| n = 255 |
6–8 n = 15 |
9–12 n = 195 |
Male n = 97 |
Female n = 119 |
English n = 205 |
Other n = 6 |
||
| A. |
Claim: Similar skeletal features likely indicate a common ancestor. Evidence: Chimpanzees and gorillas both have opposable thumbs and similar ribcages. Reasoning: Chimpanzees and gorillas have similar skeletal features. |
18% | 47% | 16% | 22% | 16% | 17% | 67% |
| B. |
Claim: Similar skeletal features likely indicate a common ancestor. Evidence: Chimpanzees and gorillas have similar skeletal features. Reasoning: Chimpanzees and gorillas both have opposable thumbs and similar ribcages. |
14% | 0% | 14% | 19% | 9% | 14% | 17% |
| C. |
Claim: Chimpanzees and gorillas may have a common ancestor. Evidence: Similar skeletal features likely indicate a common ancestor. Reasoning: Chimpanzees and gorillas both have opposable thumbs and similar ribcages. |
19% | 13% | 20% | 18% | 20% | 19% | 0% |
| D. |
Claim: Chimpanzees and gorillas may have a common ancestor. Evidence: Chimpanzees and gorillas both have opposable thumbs and similar ribcages. Reasoning: Similar skeletal features likely indicate a common ancestor. |
49% | 40% | 49% | 42% | 55% | 50% | 17% |
Post-Test (Treatment)
Answer Choice |
Overall |
Grades |
Gender |
Primary Language |
||||
|---|---|---|---|---|---|---|---|---|
| n = 301 |
6–8 n = 8 |
9–12 n = 274 |
Male n = 134 |
Female n = 150 |
English n = 274 |
Other n = 9 |
||
| A. |
Claim: Similar skeletal features likely indicate a common ancestor. Evidence: Chimpanzees and gorillas both have opposable thumbs and similar ribcages. Reasoning: Chimpanzees and gorillas have similar skeletal features. |
18% | 0% | 19% | 14% | 21% | 18% | 22% |
| B. |
Claim: Similar skeletal features likely indicate a common ancestor. Evidence: Chimpanzees and gorillas have similar skeletal features. Reasoning: Chimpanzees and gorillas both have opposable thumbs and similar ribcages. |
14% | 13% | 15% | 19% | 11% | 15% | 0% |
| C. |
Claim: Chimpanzees and gorillas may have a common ancestor. Evidence: Similar skeletal features likely indicate a common ancestor. Reasoning: Chimpanzees and gorillas both have opposable thumbs and similar ribcages. |
22% | 25% | 22% | 23% | 21% | 22% | 22% |
| D. |
Claim: Chimpanzees and gorillas may have a common ancestor. Evidence: Chimpanzees and gorillas both have opposable thumbs and similar ribcages. Reasoning: Similar skeletal features likely indicate a common ancestor. |
46% | 63% | 45% | 44% | 47% | 45% | 56% |