This scatter plot animates through different x-axis variables from the Iris Dataset, cycling between petal width, sepal width, petal length, and sepal length every two seconds via `setInterval`. Built with D3 v6, it uses `scaleLinear`, `axisLeft`, and `axisBottom` to render axes, while `selectAll('circle').data(marks).join('circle')` updates the SVG circles. The reusable chart pattern from Bostock’s "Towards Reusable Charts" is implemented through getter-setter functions in `scatterPlot.js`.