To respond to the hotly debated issue of why pidgeons bob their heads while walking I might question why we are so intrigued by this. The more obvious question might concern what happens at the other end of the pidgeon, namely, pidgeon shit which covers any and all available surfaces in most cities. True, there is no mystery involved here, merely the natural evacuation of hamburger crumbs and french fries, things that probably make up the majority of the diet of the urban pidgeon population. While the bobbing head of a pidgeon may look strange to some of you, the contributions made by the said pidgeons to the city workforce in cleaning surfaces of long dead heroes and public building facades should not be overlooked, and, in fact, should be considered a terrific alternative to unemployment. Which leads us to the possible lesson here. It’s not how or where we walk that matters, but what we leave behind.
Welcome to the Straight Dope Message Boards, quitman, we’re glad to have you with us.
When you start a thread, it’s helpful to other readers if you provide a link to the column you’re discussion. In this case, I presume, Why do pigeons bob their heads?
It helps keep us on the same page, and saves lots of searching time. No biggie, you’ll know for next time, and, as I say, welcome!
A stylish post.
i’d give it a 7.9; adjusted to an 8.4, as it seems to be his first.
Welcome, quitman! 
But you have to deduct at least one point for misspelling pigeon, which animal is technically known now as a rock pigeon, fka rock dove.