Use these targets, vocabulary, rubrics, examples, and score sheet with the instructor's approved lesson and procedure. This is an assessment companion, not a complete lesson or safety authorization.
By the end of the Comparative Anatomy unit, a student should be able to:
Five science criteria plus separately reported integration (Page 3).
Locate and explain a structure on a specimen, out loud.
The student tells homology from analogy on the specimens (Page 4).
Cross-specimen comparisons and the common-descent argument kept distinct.
You are making a decision, not adding up points. For each criterion, decide whether the work is Developing, Proficient, or Mastery — the column language tells you which. A criterion counts as mastered only when the student can both locate the structure on the specimen and explain it under questioning. Each student has three tokens per term; each token retries one rubric criterion. Approved accommodations, equipment failures, and approved absences are handled separately and do not consume these tokens.
Accept listed synonyms; use the distinction column to resolve near-matches.
| Canonical answer | Accepted synonyms | Common confusion / discriminator |
|---|---|---|
| Comparing structures | ||
| Homology | homologous structure | Same body plan and shared descent — not merely the same job |
| Analogy | analogous structure | Same function, separate origin; not evidence of descent |
| Comparative anatomy | cross-specimen study | Tracing one structure across species to line up the parts |
| Vestigial structure | reduced structure | Inherited from an ancestor but reduced in size or use |
| The defense & the argument | ||
| Dissection defense | oral defense | Explaining a structure on the specimen, aloud, under questioning |
| Common descent | shared ancestry | Species share ancestors; homology is the evidence for it |
| Homologous forelimb | shared ancestral forelimb | Tetrapod bones may be fused or reduced; not every limb has five digits |
| Owen’s “homology” | Owen’s term (1843) | Owen named it; Darwin later read it as evidence of descent |
| Criterion | Developing | Proficient | Mastery |
|---|---|---|---|
| Comparing structures across specimens | Cannot locate the same organ system in two specimens. | Finds both systems but assumes a shared job proves homology. | Compares an organ system in two specimens and distinguishes shared function from evidence of shared ancestry. |
| Homology vs. analogy | Treats any two structures that do the same job as the same structure. | Uses the words homology and analogy but applies them to the wrong examples. | Distinguishes homologous structures (shared plan, shared descent) from analogous ones (same function, separate origin) on the actual specimens. |
| The dissection defense | Cannot locate or name the requested structure on the specimen when asked aloud. | Finds and names the structure but cannot explain its function or answer a follow-up question. | Locates, identifies, and explains a structure’s function on the specimen out loud, and holds up under an instructor’s questioning. |
| The common-descent argument | Cannot relate anatomical evidence to common descent. | Names homology but treats living species as successive ancestors. | Explains the shared tetrapod forelimb pattern and places the specimens on a branching tree, stating the limits of the comparison. |
| Synthesis & careful communication | Reports expected rather than observed anatomy; handles specimens carelessly. | Names most structures but blurs observation and inference. | Uses accurate terms, separates observation from inference, and handles specimens respectfully. |
| Integration (cross-domain) | Makes no supported connection between the source and the science. | Uses the source but needs help connecting evidence, writing, or limitations to the science. | Independently connects History, Reading, and Writing using a cited source, appropriate evidence, a limitation, and a scientific explanation. |
The split between Proficient and Mastery is the specimen, not the book: a mastered defense reads the structure off the tray and holds up under a follow-up question. Ask “show me that structure and tell me what it does.”
Read these before you grade. They show what Mastery and Developing actually sound like, plus the edge cases where you should coach rather than decide on the spot.
Student: ______________________________________ Date: _______________ Guide: _________________________
| # | Criterion | Decision | Notes |
|---|---|---|---|
| 1 | Comparing structures across specimens | Dev / Prof / Mast | |
| 2 | Homology vs. analogy | Dev / Prof / Mast | |
| 3 | The dissection defense | Dev / Prof / Mast | |
| 4 | The common-descent argument | Dev / Prof / Mast | |
| 5 | Synthesis & careful communication | Dev / Prof / Mast | |
| 6 | Integration (cross-domain) | Dev / Prof / Mast |
☐ No ☐ Yes — for criterion: __________
Tokens left this term after this session (choose one): ☐ 3 ☐ 2 ☐ 1 ☐ None left
Dev = Developing · Prof = Proficient · Mast = Mastery · Unsure between two levels? Circle the lower one and note what a re-do would need.