This scatter plot visualizes the Iris dataset, showing the relationship between petal length and petal width for three flower species (setosa, versicolor, and virginica), with each species distinguished by a distinct color. It also encodes sepal length and width as horizontal and vertical radii of the circular marks, adding extra dimensions to the display. The visualization loads data from a GitHub gist via `d3.csv`, uses `d3.scaleLinear` for axes, and renders SVG circles with `d3.axisLeft` and `d3.axisBottom`. The code imports D3 v6 from UNPKG and runs asynchronously to draw the chart.