This interactive tree diagram displays a hierarchical genealogy of names loaded from a JSON file, with nodes and links rendered as an SVG. Users can click any node to collapse or expand its subtree, triggering smooth animated transitions of the layout. The visualization uses D3.js version 3.5.17, specifically the `d3.layout.tree` and `d3.svg.diagonal` APIs, with node positions calculated and updated via the `update` function on each interaction. Styling is defined in a linked stylesheet, and the example is presented as an animated, self-contained web page.