Unit 06 · Marine Reptiles, Birds & Mammals
These animals are the ocean’s returnees — reptiles, birds, and mammals whose ancestors lived on land and whose descendants went back to the sea while keeping their lungs. This unit sorts the air-breathing marine tetrapods — sea turtles and sea snakes, seabirds, and the marine mammals — and settles the classification that trips most people up: a whale, dolphin, or seal is a mammal, not a fish. You study how they dive, stay warm, feed, and migrate. Mastery means you can read a body for the adaptations that let a lung-breather thrive in the sea.
| Criterion | Not yet | Approaching | Mastered |
|---|---|---|---|
| Air-breathing marine tetrapods | Groups every large sea animal together as “fish.” | Names some marine tetrapods but cannot say what unites them. | Sorts the air-breathing marine tetrapods — sea turtles and sea snakes, seabirds, and marine mammals — and explains that each breathes air and descends from land ancestors. |
| Mammals, not fish | Calls whales and dolphins fish. | Says whales are mammals but cannot give the reasons. | Identifies whales, dolphins, and seals as mammals — they breathe with lungs, are warm-blooded, and nurse their young — and contrasts them with fish. |
| Diving adaptations | Cannot say how a mammal survives a deep dive. | Names one diving adaptation but not how it helps. | Explains diving adaptations — blubber, enhanced oxygen storage, a slowed heart rate (bradycardia), and pressure tolerance — and how each extends a breath-hold dive. |
| Thermoregulation, feeding & migration | Assumes warm-blooded animals cannot live in cold seas. | Names blubber or a feeding mode but muddles the details. | Explains how blubber holds body heat, distinguishes baleen filter-feeding from toothed hunting, and links long migrations to feeding and breeding grounds. |
| Lab technique (marine-mammal adaptation analysis) | Skips the measurement or records no result. | Runs the model but reads it carelessly. | Runs a clean marine-mammal adaptation analysis — a blubber-insulation model or diving-physiology investigation — measured, recorded with units, and tied back to the animal. |
| Integration (cross-domain) | Treats the science as isolated facts; makes no cross-domain connection. | Names a link to history, reading, or writing but cannot defend why it matters. | Connects the unit to its anchor across History · Reading · Writing (plus chosen electives) and defends why the connection matters. |
“A humpback is a mammal, not a fish — it surfaces to breathe with lungs, it’s warm-blooded, and it nurses its calf. On a deep dive its heart rate drops and its blubber both insulates and stores energy. My blubber model held its temperature far longer than the bare-water control.”
“Whales are just big fish, right? They stay warm because… the water’s warm? I’m not sure how they hold their breath so long.”
You demonstrate this unit through the marine-mammal adaptation analysis plus short oral checks where you reason from your measurements aloud — not a multiple-choice test. A criterion counts as mastered only when you can both run the investigation and explain the diving and thermoregulation biology behind it. Mastery is demonstrated, not awarded.
A 5-page clipboard packet — unit overview, key terms, the mastery rubric, anchor examples, and a score sheet you can print and grade against.