Song 300 (Rush--"Natural Science")

I figured that with this being my 300th pick, I needed a special song to choose. This was not one of my favourite songs from Rush, however at the recent concert that I attended they really impressed me with performing this song in its entirety.
This one is one of the last bastions of the Rush '70s long, epic "concept" songs; it contains three parts: I. Tide Pools (2:21) II. Hyperspace (2:47) III. Permanent Waves (4:08). The main subject matter of the song is about the scientific theories pertaining to the rise of life and civilizations on Earth. From what I understand the song was written quite quickly during the recording session.

Here is the studio version on YouTube.
Here is a live performance on YouTube.

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