Leor Pantilat posted the route:
The Evolution Loop is a magnificent route through some of the most inspiring terrain in the High Sierra. Technically the route is not a loop as the start and finish are at different locations (more accurately, it’s a horseshoe) utilizing the North Lake and South Lake trailheads in the Eastern Sierra outside of Bishop (note: the trail and/or road segment that links these two trailheads would not be fun). The "loop" entails ~55-56 miles and 10,000+ ft elevation gain including three high passes – Piute Pass (11,400 ft), Muir Pass (12,000 ft), and Bishop Pass (11,960 ft). Bishop Pass and Piute Pass are on the Sierra Crest while Muir Pass is on the Goddard Divide. About 25 miles of the route are on the John Muir Trail passing by the famous Evolution Valley/Basin and the iconic Muir Hut at Muir Pass. The sections off the JMT include spectacular Dusy Basin and Humprehy's Basin.
I found a nice map of the route online here (although mileage estimates are off in spots)
TrailRunner July 2012 article on Fastpacking the Evolution Loop
A shorter option (37 miles / 9,200' elevation gain) is as follows:
The Evolution Loop via Lamarck Col is an abbreviated route that follows the original Evo Loop after surpassing Lamarck Col (12,880 ft) and holds roughly the same amount of overall elevation gain. With incredible terrain of the High Sierra and difficult passes, this Loop is ~37-38 miles with close to 10,000 ft elevation gain. The three high passes are Lamarck Col Pass (12,880 ft), Muir Pass (12,000 ft) and Bishop Pass (11,960 ft).