This example shows an animated tree chart of the animal kingdom, with circles sized by value and colored by type for each taxonomic group, connected by curved links with color-coded levels. Using d3.hierarchy and d3.tree, the code positions nodes in a hierarchical layout, then renders the structure as SVG paths and circles. Data is embedded directly in the source, with node circles and links styled via D3’s selection and attribute methods, all running within a React framework using D3 v5.