```json { "proposals": [ { "join_class": "category", "column": "iris.species", "kind": "external_candidate", "entry_id": null, "name": "IUCN Red List conservation status data", "probable_url": "https://www.iucnredlist.org/resources/spatial-data-download", "license_expectation": "CC BY-NC 4.0 (non-commercial use)", "join_story": "Joining conservation status would let this dataset contextualize iris species measurements within their ecological vulnerability, showing whether morphological patterns correlate with threatened versus stable populations.", "teaches": "Whether the species you're measuring face conservation concerns that might affect sampling availability or research priorities." }, { "join_class": "category", "column": "iris.species", "kind": "external_candidate", "entry_id": null, "name": "GBIF species occurrence records", "probable_url": "https://www.gbif.org/", "license_expectation": "CC0 or CC BY (varies by dataset contributor)", "join_story": "Joining global biodiversity occurrence data would enrich species records with geographic distribution patterns, letting this dataset compare measured specimens against known habitat ranges and collection locations worldwide.", "teaches": "Where in the world these species naturally occur and whether your measurements align with specimens from their native versus cultivated ranges." } ] } ```