A mini-documentary posted on the news site Vox wastes no time addressing the leading criticism of one of the most urban and synanthropic animals, the pigeon. People often complain that the animal shits too much (each bird produces an estimated 25 pounds a year), and that this shit, which accumulates and hardens along the exterior of buildings, or in the dusk of neglected attics, or on sections of a sidewalk that are beneath stretches of telephone cables beloved, for some reason or another, by a loft, is nothing but a paradise for diseases that are as ugly as the shit they thrive in. It gets worse.

There was even a moment near the middle of the 20th century when pigeon shit was confused with the sound of our universe's birth, the cosmic microwave background. Wikipedia:

The [scientists] were certain that the radiation they detected on a wavelength of 7.35 centimeters did not come from the Earth, the Sun, or our galaxy. After thoroughly checking their equipment, removing some pigeons nesting in the antenna and cleaning out the accumulated droppings, the noise of remained.

And so the story of how we discovered the relic radiation that provided strong evidence for the big bang theory, our deepest understanding of our origins, cannot be told without pigeon shit.

But the prominence of pigeons is not new. As this mini-documentary points out, they figure in the opening chapter of the founding text of modern biology, Charles Darwin's On the Origin of Species. These birds helped millions of people see that the earth is really, really old, and that life is not static but constantly changing with changes in the natural environment or, as in the case of the pigeons in Darwin's book, changes in the tastes of humans.

Also, and this is not mentioned in the Vox doc, pigeons shed light on the roots of religion. It was revealed in an experiment conducted by the American behaviorist B.F. Skinner. What happened was this: Skinner put a pigeon in a box rigged with buttons and a feed delivery system. Even a pigeon can't resist pushing buttons. And the food functioned as a reward for the captive bird. But Skinner rewarded the bird at random. Pecking this button or that offered no ordered result. The food just just fell into the box without rhyme or reason. And what happened? Well, if the food dropped while the pigeon happened to have its neck turned to the left, the poor thing assumed that turning its neck to left had done the trick. The pigeon would turn its neck again in that way, and by luck food fell into the box again. That was it. The bird believed in the church of turning the neck to the left. Skinner called it "superstitious behavior."

And there is also the matter of pigeon feet, but I have already written about that. My point is we should show more respect and sympathy to this bird. It has been good to us.