But it's when they do their little hopping run and unfold those great wings and launch their improbability into the air, a hundred, a thousand at a time, then get aloft and straighten a thousand necks and beaks, and stream their legs out behind like an afterthought, and get to cruising altitude and cover continents with that great slow steady wingbeat, flying in Vs or Ws or strange shifting ideograms -- that is the essence of cranishness. With all my other cranish features coming out, I can't wait till I get my cranish wings. I dream of flying -- probably we all do, and they are exhilarating dreams; I wake up -- and come down, and, for that waking moment, I long for the time when I can trade the big brain for the big wings and really learn to fly, learn to really fly.

There's something else that makes humans cranish: We're all cultural animals to some extent -- which is to say, animals that pass along some of what we are through intergenerational teaching rather than just inbred instinct. (I say this makes us cranish, rather than saying it makes them more human -- they've been around so much longer than we have.) Unfortunately, recent situations in cranedom make one wonder if cultural transmission of important stuff is a good survival strategy.

This doesn't directly involve the thousands of sandhill cranes we see flying through every spring. It involves the cranes we don't see -- the sandhill's cousin, the whooping crane. A little larger than the sandhill crane, the whooper is cursed with brilliant white and black plumage, in contrast to the camouflage gray-browns of the sandhills. This made it attractive to the same kind of "hat hunters" that decimated the American beaver population. And it was also unlucky in its habitat selection, preferring Florida to Texas.

While the sandhill cranes continued to fly up and down the continent in hundreds of thousands, the whooping cranes dwindled to only 45 known cranes by the middle of the 20th century. Because it is a big bird, beautiful in its cranish way, its plight helped encourage the passage of the Endangered Species Act, which made humans the first species on earth ever to show evidence of really caring about its own impact on the rest of the planet.

A small industry has now evolved (I don't use the term loosely) around keeping whooping cranes alive as a species. It begins with nest raiders at the birds' last known brood site in southern Canada; cranes typically lay two eggs, but frequently only one chick survives. So one egg is heisted from each nest and taken to a crane-raising facility near Baraboo, Wis. There, the eggs are hatched and the chicks raised, through a process straight from a Dickens novel. These cranes are orphans, after all. How will they learn?

Specifically, cranes don't know where to migrate. The desire to migrate is apparently inbred, but the destination is cultural -- learned from the experience of accompanying the parental flock on its migration. And if there is no flock, there is no one to transmit that experience.