This interactive scatter plot visualizes penguin measurements of bill depth and length, colored by species. The visualization uses React with D3 v7 to render SVG circles, mapping species to an ordinal color scale. An interactive color legend allows users to hover over a species name, which triggers a cross-filtering effect: other species' marks fade to 20% opacity while the selected species remain prominent. The axis components are custom-built, utilizing D3’s scaleLinear with nice ticks and a formatter that abbreviates large numbers.