**The most important metric is `petal_length`, because it separates the three species better than any other measurement.** This is a judgement based on the per-species ranges below, not a formal feature-importance test. **Why petal length** - **Setosa** petal length runs 1.0–1.9 (average 1.46). That never overlaps the other two species, whose minimums are 3.0 and 4.5. - **Versicolor** runs 3.0–5.1 (average 4.26) and **virginica** runs 4.5–6.9 (average 5.55). They overlap only in a narrow band of 4.5–5.1. - **Sepal width** is much weaker. The species averages are 3.43, 2.77 and 2.97, and the ranges overlap heavily: 2.3–4.4, 2.0–3.4 and 2.2–3.8. - **Sepal length** is also weaker. Versicolor (4.9–7.0) and virginica (4.9–7.9) overlap across almost their whole range. - **Petal width** follows a similar pattern to petal length, with averages of 0.25, 1.33 and 2.03. Petal length has the wider spread between species, so I rank it first. **Highest and lowest records by petal length** - **Highest:** a virginica specimen with petal length 6.9, petal width 2.3, sepal length 7.7 and sepal width 2.6. - **Lowest:** a setosa specimen with petal length 1.0, petal width 0.2, sepal length 4.6 and sepal width 3.6. The extremes come from opposite species. The longest petal is a large virginica and the shortest is a small setosa, which fits petal length being the dominant feature for telling the species apart. The figures come from the per-species summary (`iris_by_species`) and a raw-table query for the top and bottom records by `petal_length`.