Glee Tree Hugger Video Surfaces
You see, Mark -- an outspoken bird advocate -- is a member of the Echo Park Ornithology Club in Los Angeles.
And three years ago, right before Mark struck it big on "Glee" -- he expressed his pride in the animal organization by whipping out his guitar at a park meeting ... and jamming out an EPOC theme song he wrote.
You probably wouldn't guess from the lyrics -- but the song's called "Echo Park Ornithology Club." more on this story
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