Astonishingly, today is the fifth anniversary of the publication of Blötzmann’s historic bird psychology diagram. Ornithologists throughout the world will be celebrating this landmark in a manner only ornithologists can, that is, by gathering upon promontories peering at the sky while munching filberts.

(Click on the diagram for a larger image,)

It is hard to put into words the earth-shuddering ramifications occasioned by Blötzmann’s diagram. Certainly it has had immeasurable effects upon the way we puny humans apprehend our beakéd, wingéd, airborne pals. I for one am reduced to dribbling with joy that I no longer languish in bird-ignorance, as I sadly did until this day five long years ago.

UPDATE : Inexplicably, several errors crept into the reproduction of Blötzmann’s diagram. The corrected version appears below, and will, again, loom larger should you click upon it.