This interactive tree diagram visualizes a hierarchical classification of animals, using color-coded nodes to distinguish four taxonomic levels. Built with D3.js v3 and SVG, the visualization loads data from a JSON file and supports zooming, panning, and click-to-expand interactions. The layout is computed with `d3.layout.tree`, while link text and custom tooltips display additional details. Animated node transitions and CSS-styled elements enhance readability, though the dataset contains an inconsistent label referencing “plants” within the cold-blooded branch.