Really swingin', man...

I had always assumed that people swinging their arms when they walked was somehow a balance thing. I never gave it much thought though. Pendulums are often used to keep the balance of tall, skinny structures and that is what arms essentially are when you're walking: swinging pendulums.

Now, I read this article, which states that arm swinging is largely believed to be an evolutionary carry-over "from when we used to go about on all fours," but now a new paper reveals that the purpose of arm swinging may actually be balance and energy economy. Really? That former was the default theory? Huh.

"Rather than a facultative relic of the locomotion needs of our quadrupedal ancestors, arm swinging is an integral part of the energy economy of human gait."

Well, yeah. Didn't you ever try to walk with your arms straight your sides when you were a kid just to see what it felt like? I was under the impression that this was a near-universal childhood curiosity.

This is not the first time in recent memory that I've read about an allegedly interesting scientific paper making some common sense claim that was causing a stir. A few months ago I read an article about a computer science professor named James Crook who claimed to have an algorithm for solving sudoku puzzles.

His system requires players to mark up empty cells in a Sudoku grid with all possible remaining numbers and, by comparing number sets, to labour through a tree of options that eventually produces a solution.

That's pretty much the method I, and everyone else I know, use to solve sudoku puzzles. Am I missing something?

-M.