Science Assessment

A class of students is visiting a natural history museum. Students are looking at the skeleton of a dog, after which they walk over to an exhibit showing the skeleton of a fish.

As a homework assignment the teacher asks the students to think about the following question:

 “Do dogs and fish share a common ancestor?”

Students are asked to write an argument to justify their answer. One student writes:

Common ancestors are a topic in evolution. Similar skeletal features likely indicate a common ancestor.  Dogs and fish have similar anatomical features. For example, they both have a backbone, a bony skull, and their ribcages are similar. Dogs and fish may have a common ancestor.

Identify the claim, evidence, and reasoning statement in the student’s argument.

1. Claim: Similar skeletal features likely indicate a common ancestor.

   Evidence: For example, they both have a backbone, a bony skull, and their ribcages are similar. 

   Reasoning: Dogs and fish have similar anatomical features.

2. Claim: Similar skeletal features likely indicate a common ancestor.

   Evidence: Dogs and fish have similar anatomical features.

   Reasoning: For example, they both have a backbone, a bony skull, and their ribcages are similar. 

3. Claim: Fish and dogs may have a common ancestor.

   Evidence: For example, they both have a backbone, a bony skull, and their ribcages are similar.

   Reasoning: Similar skeletal features likely indicate a common ancestor.

4. Claim: Fish and dogs may have a common ancestor.

   Evidence: Similar skeletal features likely indicate a common ancestor.

   Reasoning: For example, they both have a backbone, a bony skull, and their ribcages are similar