Domain: Natural Science — Ecology & Evolutionary Biology
Target concept: Foraging of ants is disrupted by sudden habitat fragmentation (crossing paper board barriers)

Video generation prompt: On a sunlit ground, foraging ants traverse back and forth between their nest and a food source. At this time, a flat piece of cardboard is placed in the middle of their travel path and remains there throughout.

Evaluation guide:
(i) Target concept: Habitat fragmentation induces rapid, observable disruption of ant foraging trails via loss of sensory continuity (visual + chemical).
Minimum mechanism: Cardboard must be opaque, stationary, and planar to block both line-of-sight and pheromone diffusion; ants must rely on trail-following (not solo exploration); sunlit condition ensures visual cue dominance and eliminates nocturnal confounds.
(ii)Storyline: [Phase 1] Ants move in straight, continuous lines between two fixed points (nest ↔ food) under steady sunlight. [Phase 2] Cardboard is already in place; first ant reaches its edge → immediate full-stop (≤1 sec after contact). [Phase 3] Multiple ants accumulate at edge → synchronized pause → lateral detour or reversal begins. [Phase 4] Trail visibly fractures: no motion vector crosses cardboard; new paths emerge parallel or angled away. [Phase 5] All motion remains confined to ground plane; no aerial, tunneling, or penetrating behaviors. Perspective: Fixed overhead or low-angle side view ensuring full visibility of ant-cardboard-ground spatial relationship; no occlusion of cardboard edge or ant contact zone.

Manual:
Experimental Procedure
1. Place a flat, opaque cardboard sheet horizontally on sunlit bare ground.
2. Position ant nest and food source at opposite ends of a straight foraging path across the ground.
3. Record 10 seconds of continuous ant movement along this path as they encounter the stationary cardboard barrier.
Observation of Experimental Phenomena
Ants approach cardboard edge, halt completely, then collectively detour laterally or reverse direction—no ant crosses the cardboard surface; the originally linear foraging trail becomes fragmented and discontinuous.
Summary of Experimental Principles
Habitat fragmentation disrupts pheromone trail continuity and visual navigation cues, causing immediate path interruption and collective reorientation—demonstrating how physical barriers impair foraging efficiency in social insect colonies.

Prompt Grounding rubric:
level_1: No ants are visible; no cardboard is present; no ground surface is shown; the scene is not lit as sunlit outdoor ground; there is no implied nest-to-food path.
level_2: Ants are present and moving, but not along a single back-and-forth path between two fixed points; the cardboard barrier is missing or replaced by a different object (e.g., a rock or plastic sheet); the ground looks shaded or indoor rather than sunlit.
level_3: Ants move along a sunlit ground surface; a flat, stationary piece of cardboard sits in the middle of their travel path; ants remain visible on both sides of the cardboard for the entire clip; the ants' consistent inbound/outbound movement implies a nest-to-food path even though neither is explicitly labeled.
level_4: All elements from 3-score are present, and the cardboard is visually distinct from the ground (different color or texture) and stays flat and in the same spot for the full clip; ants remain continuously visible somewhere in frame throughout the 10 seconds; no unrelated objects or scene cuts interrupt the shot.
level_5: All elements from 4-score are present, and the cardboard sits centrally across the path, splitting it into two clearly visible halves; the ground shows a single, consistent sunlit look (shadows all pointing the same way) for the entire clip; the camera framing keeps the cardboard, both sides of the path, and the ants fully in view with nothing cropped or blocked.

Scientific and Causal Correctness rubric:
level_1: Ants show no behavioral response to the cardboard at all: they either pass straight through it as if it weren't there, or halt with no other observable reaction; the barrier appears to have zero effect on foraging behavior.
level_2: Ants slow down near the cardboard but keep walking across it as though it isn't a solid barrier, or the cardboard looks translucent in a way that lets ants pass through; there is no visible turning or backing-up response, and no contrast between movement before versus after reaching it.
level_3: The cardboard is opaque and solid; ants stop when they reach its edge; at least one ant turns, loops back, or backs away after contacting the edge; no ant is seen crossing over the cardboard's surface; the once-continuous foraging line is visibly interrupted at the barrier.
level_4: All elements from 3-score are present, and several ants (three or more) show a shared response: pausing together at the edge, then collectively turning aside or reversing; the foraging trail visibly splits or gaps at the barrier; no ant resumes its original straight-line path until after it has gone around or away from the cardboard.
level_5: All elements from 4-score are present, and essentially every ant that reaches the cardboard's edge halts almost immediately and then moves only sideways or backward, never forward through or over the cardboard; the break in the foraging trail at the barrier is unmistakable, and the sequence of events (ants approaching, halting, turning away, trail splitting) reads clearly in order.

Spatiotemporal Consistency rubric:
level_1: Ants jump to new locations between frames; the cardboard flickers, spins, or changes size or position suddenly; the ground surface warps or vanishes; the lighting flips abruptly (e.g., sunlit to overcast in under a second); ants blink in or out of existence; motion looks jerky with more than a couple of visible freezes or skips.
level_2: The cardboard shifts sideways or tilts partway through the clip; an ant's speed changes abruptly at least twice (e.g., instantly stopping then instantly sprinting); the shadows point a different way than the apparent sun position; ants appear to overlap or pass through each other; the background shifts independently of the ants' motion.
level_3: The cardboard stays in the same position and orientation throughout; ants move with smooth, continuous motion with no freezing, jumping, or overlapping errors; shadows point the same direction and have the same softness across the clip; the ground stays stable and evenly textured; the overall motion reads as one continuous, coherent sequence.
level_4: All elements from 3-score are present, and the ants' apparent size and the camera's perspective stay constant (no sudden zoom or distortion); the cardboard's edge stays crisp and level with the ground throughout; the ants are spaced and grouped naturally rather than in obviously repeating or evenly spaced clusters; the lighting stays even with no sudden flares or brightness jumps.
level_5: All elements from 4-score are present, and every ant's path looks smooth and continuous with no visible strobing, warping, or trembling; the cardboard looks rigid and solid throughout, with no bending, flexing, or wobbling; the ants' legs move in a natural, alternating walking rhythm rather than sliding along the ground; the ground shows no lens artifacts like flickering color fringes or shifting focus.