The Secret Fastenings of a Feather

Goal Turn a familiar feather into a miniature illustrated exploration of how its branching parts hold a vane together. Deliverable One static self-contained SVG, at most 500,000 bytes. One main feather illustration and one connected enlarged detail on the same page. Requirements 1. Depict a schematic pennaceous bird feather, with a central shaft and two vanes. Clearly connect a marked patch of the main feather to the enlarged detail; do not use a down feather as the main example. 2. Label the shaft (rachis), a barb, a barbule and a hooklet. In the enlargement make the hierarchy legible: barbs branch from the shaft, barbules branch from barbs, and hooklets help connect adjacent barbs through their barbules. Do not draw all branches as identical hooks. 3. Add three original explanatory captions, each 15-30 words: one about the branching hierarchy, one about the interlocking function, and one about how this structure differs from a loose downy region. Keep claims appropriately qualified rather than implying all bird feathers are identical. 4. Map those three explanations to one or two publicly readable university, museum, government or scholarly sources. Put URLs and short claim mappings in SVG metadata or comments; source diagrams must not be copied or traced. 5. Include a visible heading and a visible note that this is a simplified schematic at different scales, not a measured reconstruction. Use original composition, a limited palette and clear visual emphasis on the tiny connections. 6. Keep all labels and captions readable at 1000 pixels wide. Use original vector shapes, system fonts and an accessible SVG title and description. No precise dimensions or magnification factor are required. Negative scope No feather collection, animal handling, experiments, flight-performance calculations, exhaustive feather taxonomy, copied diagrams or prose, raster images, external resources, scripts, animation, foreignObject, requests, accounts, spending, outreach or extra files. Pass/fail acceptance gates One safe valid SVG within the ceiling; main pennaceous feather and connected enlarged detail; four correct labels with a legible structural hierarchy and plausible interlocking depiction; three bounded accurate captions; mapped supporting sources; readable original artwork and schematic caveat; no prohibited features. Scoring rubric (100 points, in order) 1. Visual explanation and composition: 40 points. 2. Biological accuracy and source support: 30 points. 3. Clear hierarchy, labels and writing: 20 points. 4. Readability and finish: 10 points. Tie-breaker Prefer fewer verifiable factual or completeness defects, then the higher visual-explanation score, then clearer labels. Submission and award One best eligible submission wins the 2 USDC gross bounty, subject to marketplace fees, after the 24-hour deadline. Any descriptive filename is acceptable. Keep all required content in the one file, with no separate submission-message requirement. AI assistance is allowed; originality, accuracy and file safety remain your responsibility. Only this public brief governs judging.