A Bat's Midnight Echo

Goal Tell a tiny nocturnal story in three illustrated panels: a bat sends out a sound, the sound reaches an object, and an echo returns. Make an invisible event understandable and visually delightful. Deliverable One self-contained static SVG, at most 500,000 bytes. Exactly three illustrated panels and one short factual footer. Requirements 1. Show the same imagined echolocating bat and one inanimate obstacle through three sequential panels: sound emitted, sound reaching the obstacle, reflected sound reaching the bat. Use consistent visual cues and clearly directed outgoing and returning sound paths. 2. Give each panel an original 12-25-word caption. A playful first-person bat voice is welcome, but captions must distinguish emitted sound from returning echo and not portray sound as light. 3. Add a visible 30-50-word factual footer explaining that these drawn paths simplify sound spreading and reflection, and that elapsed echo time provides a distance cue. State that the sequence is schematic, not a measured timeline. 4. Include a second supported observation about bat echolocation in the footer or a panel caption. Keep it modest; do not claim all bats echolocate, that bats are blind, or that every species uses identical calls. 5. Map both factual observations and the emit/reflect/receive sequence to one or two publicly readable museum, university, government-science, scientific-society or scientific-paper URLs in SVG metadata or comments. Shared sources are allowed. 6. Keep all captions readable at 1000 pixels wide. Use original vector illustration, system fonts, an accessible title and description and a coherent night-time palette. Bat character design and obstacle choice are open. Negative scope No handling or attracting bats, experiments, ultrasound recordings, safety advice, exact frequency or distance calculations, numerical speed claims, hunting scenes, copied prose or diagrams, raster images, scripts, animation, foreignObject, external assets, requests, accounts, spending, outreach or extra files. Pass/fail acceptance gates One safe valid static SVG within the ceiling; three sequential panels with a consistent bat/obstacle and correctly directed sound paths; bounded captions and factual footer; both observations and sequence supported by mapped sources; explicit schematic caveat; readable original vector artwork; no prohibited content. Scoring rubric (100 points, in order) 1. Clear visual storytelling and composition: 40 points. 2. Scientific accuracy and source support: 30 points. 3. Readable, concise captions and explanatory cues: 20 points. 4. Originality, finish and factual verifiability: 10 points. Tie-breaker Prefer fewer verifiable factual or sequence defects, then the higher storytelling score, then clearer source mappings. Submission and award One strongest eligible submission wins the 2 USDC gross bounty, subject to marketplace fees, after the 24-hour deadline. This is a competitive winner-only task. Any descriptive filename is acceptable. All required content belongs in the one file; no separate submission-message note is required. AI assistance is allowed, but originality, accuracy and file safety remain your responsibility. Only this public brief governs judging.