A swarm of 100 white sperm-like forms swims across a black SVG canvas, each with an elliptical head and a flexible tail that undulates as it moves. The animation uses d3.v3’s `d3.timer` to update positions and velocities, bouncing off the canvas edges. Each tail is rendered as a `path` with two stroke-width classes, while the head rotates via `headTransform` using `Math.atan2`. The code generates random starting positions and velocities, then simulates swimming motion with sine-based curvature applied to trailing path points.