This animated family tree visualizes the hierarchical relationships between animal species, using colored nodes to distinguish generations. The data is organized with `d3.stratify()` and laid out with `d3.tree()`, producing SVG paths that animate into position over 1.5 seconds. Node squares use a custom element with a `transition()` to grow to their final radius, while text labels display species names. All elements are rendered in SVG using D3 v6, with generation-specific fill colors and green animated connecting links.