Song 536 ( Jethro Tull - Locomotive Breath )

I noticed that today is Charles Darwin's 200th birthday; I immediately knew what song to choose for today! This is one of Jethro Tull's most recognizable songs and has been covered a number of times, mostly by Metal acts.
The song is about, as Ian Anderson put it: "It's an analogy of the unending train journey of life; you can't stop, you've got to stagger on," this is expressed through the symbolism of an out-of-control train crashing down the track.
The connection to Charles Darwin is at the end of the chorus: "... old Charlie stole the handle, and the train won't stop going, no way to slow down."

Here is the studio version on YouTube.
Here is a live performance circa '82 on YouTube.

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