This visualization combines a multi-series line chart and a grouped bar-and-line chart to explore the Iris dataset. The top chart plots sepal length against petal length for each species, using d3.line paths and a d3.scaleOrdinal color legend. The bottom chart displays average sepal and petal widths per species using d3.scaleBand rectangles for bars and a d3.line path with circles for the petal-width trend. All data is loaded asynchronously via d3.csv from a GitHub-hosted CSV file, and rendered as SVG with axes from d3.axisBottom and d3.axisLeft.