Domain: Natural Science — Ecology & Evolutionary Biology
Target concept: When disturbed, woodlice curl into a ball (a defensive behavior against predators).

Video generation prompt: A pillbug on moist soil was gently touched by a human finger, and its response was observed.

Evaluation guide:
(i) Target concept: Mechanosensory-triggered conglobation reflex in terrestrial isopods.
Minimum mechanism: Intact cuticular mechanoreceptors on dorsal surface must detect tactile stimulus; functional neuromuscular coupling must enable synchronous segmental flexion; exoskeletal hinge joints must permit full 360° enclosure without fracture or dislocation.
(ii)Storyline: [Phase 1: Baseline] Pillbug rests motionless on moist soil, body fully extended, legs and antennae visible, dorsal surface exposed. [Phase 2: Stimulus] Human finger enters frame and contacts dorsal midline; contact must be singular, brief, and non-dragging. [Phase 3: Response Onset] Within the same continuous motion sequence, anterior segments begin flexion, followed by progressive posterior curling (no pause or reversal). [Phase 4: Completion] Fully enclosed spherical shape achieved, with zero ventral exposure and no appendage protrusion. [Phase 5: Sustained State] Curled form remains static until video ends. Perspective constraint: Fixed frontal/slightly overhead view ensuring full visibility of pillbug shape, soil contact, and finger contact point; no occlusion of key anatomy.

Manual:
Experimental Procedure
1. Place a live pillbug (Armadillidium vulgare) on moist, dark soil in shallow dish.
2. Gently touch its dorsal surface once with fingertip — no pressure, no dragging.
3. Observe immediate behavioral response for up to 10 seconds.
Observation of Experimental Phenomena
The pillbug rapidly withdraws all legs and antennae and curls its body into a tight, closed spherical shape — completely enclosing its ventral side.
Summary of Experimental Principles
When disturbed, woodlice curl into a ball as a defensive behavior against predators — an innate, reflexive response mediated by mechanoreceptors triggering coordinated musculature contraction.

Prompt Grounding rubric:
level_1: No pillbug is shown; no moist soil is visible; no human finger or touching action appears; and no behavioral response is depicted at all.
level_2: A pillbug and moist soil are both visible, but no finger ever enters the frame; or a finger enters the frame but never actually touches the pillbug; or the finger touches the pillbug but no reaction of any kind follows.
level_3: A pillbug rests on moist soil; a human finger enters the frame and touches it; the pillbug's posture visibly changes in response (e.g., it begins curling or draws its legs inward), but the curling stops short of a closed ball, or it is unclear whether a ball shape was reached.
level_4: Everything required for score 3 holds, and in addition: the finger's contact with the pillbug is unambiguous; the pillbug curls into a compact, fully closed spherical shape with legs and antennae withdrawn and the dorsal (top) surface fully domed over; the whole sequence plays out in one continuous shot with no cut or object substitution.
level_5: Everything required for score 4 holds, and in addition: the pillbug is motionless right up until the touch; curling begins essentially the instant contact is made, with no noticeable delay; the closed-ball shape, once reached, is held without any re-opening, wobble, or further disturbance for the rest of the clip.

Scientific and Causal Correctness rubric:
level_1: The pillbug shows no defensive response to the touch at all (e.g., it walks away, freezes rigidly, or extends its legs further); or it moves in a way inconsistent with any real animal (e.g., appears to float, stretch, or split apart); or it only ever curls partway and stays that way regardless of the touch.
level_2: The pillbug moves after being touched, but the motion is not a curling response (e.g., it scuttles sideways, jerks upward, or spins in place); or it curls before being touched, with no stimulus driving it; or it curls briefly and then fully uncurls again before the clip ends, so no lasting defensive posture results.
level_3: The pillbug curls in direct response to the touch, and the curling clearly starts only after contact is made (not before, and not with a long unexplained delay); however, the response is only a partial defense: for instance the curling starts more than about a second after contact ends, or the reaction looks more like a generic startle than the specific whole-body curling response.
level_4: Everything required for score 3 holds, and in addition: curling begins essentially immediately upon contact and proceeds as one uninterrupted motion from anterior segments curling first through to the posterior; the pillbug shows no contradictory behavior once curled (e.g., it does not resume walking, twitch open, or otherwise act inconsistently with a genuine defensive reflex); the response is clearly caused by the touch and by nothing else (no other disturbance precedes it).
level_5: Everything required for score 4 holds, and in addition: the segmental curling motion looks anatomically natural throughout (flexion proceeds smoothly from front to back with no segment moving out of sequence or reversing direction), and the pillbug shows no sign of distress or damage inconsistent with a healthy reflex response (e.g., no jerking that looks like injury, no asymmetric or lopsided curling); the behavior overall reads as the same reflexive response a real pillbug would show, from stimulus to sustained curled posture.

Spatiotemporal Consistency rubric:
level_1: The pillbug or the finger jumps to a different position with no motion in between; the lighting flips abruptly (e.g., full shadow to full brightness) partway through; the pillbug's size suddenly changes with no corresponding movement; or part of the pillbug's body (e.g., its head) disappears in one frame and comes back in the next.
level_2: The pillbug's position changes with an abrupt cut rather than visible movement; the finger appears or disappears without visibly entering or leaving the frame; the soil's texture or moisture look changes suddenly (e.g., dry to glistening) with no cause; or the curling motion skips: for instance a leg is extended in one frame and fully withdrawn in the next with no in-between motion shown.
level_3: The pillbug and finger keep consistent positions relative to the soil and each other apart from the intended touch and curling motions; the finger's approach into contact is a smooth, continuous motion; the pillbug's transition from resting to curled is shown as one ongoing motion rather than jumping between end states; nothing flickers, vanishes, or visibly warps. A small amount of blur during the fastest part of the curling motion is acceptable.
level_4: Everything required for score 3 holds, and in addition: the camera itself never pans, tilts, or zooms; the pillbug always appears properly resting on the soil surface (never floating above it or sinking into it); the finger's contact point and angle stay physically sensible (e.g., the fingertip touches the pillbug's back, not passing through it); the foreground pillbug and background soil move together consistently, with no mismatched depth cues.
level_5: Everything required for score 4 holds, and in addition: the finger visibly slows down as it approaches contact rather than stopping instantly; the curling proceeds strictly front-to-back through the body segments with no segment moving out of order or snapping back; if the finger passes in front of or behind the pillbug at any point, it does so along one consistent, physically sensible path rather than popping between depths; any indentation of the soil under the finger or pillbug looks minimal and consistent with a soft, moist surface rather than appearing or vanishing abruptly.