This scatter plot visualizes the Penguin dataset, mapping `__year_resale_value` on the x-axis and `body_mass_g` on the y-axis, with points colored by penguin species using a custom marker function. The visualization uses D3 v5’s `scaleLinear`, `extent`, `axisLeft`, and `axisBottom` APIs to render axes and scales, while SVG circles are positioned with the `join` pattern. Data is loaded asynchronously from a CSV via `d3.csv` and rendered inside a React app with an SVG canvas.