Monday, February 07, 2005

BLAKEMAN VS. MW ON BIRD BRAINS

BLAKEMAN VS. MW ON BIRD BRAINS

When I received John Blakeman's latest essay, responding to Donna Browne's observation of a puzzling aspect of Pale Male's nest-building technique, [see below - 2/5/05] I was taken aback. "Merely feathered flying dinosaurs" ? "Meager mind"?? Our hawks???

I remembered last week's article in the NY Times Science section about the avian brain, the one with the headline "Minds of Their Own: Birds Gain Respect." I wondered if John Blakeman reads our local daily in Huron Ohio. So I e-mailed him the article [with a respectful though challenging note.].

Within a few hours I received an answer. Not surprisingly, he HAD read the NY Times article. And he stood by his guns nonetheless.

Re-reading the article in light of John Blakeman's reply, and re-reading his first letter, I decided that indeed, he was right. My bristling at the "meager brain" assessment was certainly anthropomorphism on my part. I had always known that the corvid family were the Einsteins of the avian class. I just didn't want OUR BELOVED HAWKS to be relegated to the dunces' corner.

But really, Blakeman wasn't doing that. He was separating emotions from facts. I felt a bit sheepish, Then I began to think about Blakeman's various descriptions of his relationship with his trained redtail, Savanna. Don't I detect quite a bit of emotion in those passages? This made me feel a bit better about my quite unscientific reaction, though in truth his emotion doesn't ever seem to temper his scientific conclusions.

I hope this note makes a difference for those of you who find you have the same first reaction that I did.

You'll find below, Blakeman's first letter, and then his second letter, written after I sent him the NY Times article.


FIRST LETTER BY JOHN BLAKEMAN, RECEIVED AROUND 3 P.M ON 2/7/05

Marie,

A quick comment on Donna Browne's delightful nest activity observations.

She noted, “By 3:10 Lola was sitting on the center light of the Carlyle and Pale Male made trip after trip bringing twigs. Upon bringing one multi branched twig to the nest and working to adjust it for six minutes, Pale Male took it in his beak once again, left the nest circled, came back with the same twig and then placed it. (?)

Her question mark is reasonable. Why would the bird spend six minutes trying to get it placed or adjusted “just right,” and then fly off and return with the same twig and casually place it in the nest again? This didn't look sensible to Donna, and she questioned it, as she should have.

This kind of unreasonableness will be commonly seen when watching red-tails at length. The bird was deeply involved in trying to get the stick right where he wanted it for six minutes. Then, for no apparent reason he flew off with it, returned, and just put the stick in the nest with no concern. What gives?

It’s this. The cerebrum of red-tailed hawks isn't too large. Their brains are rather small, and a great deal of neural capacity must be devoted to the processing of visual images and remembering successful hunting experiences. If you can't see nor capture your daily food, you are a soon-dead hawk. Other things can happen somewhat crudely. Hunting and flying can't.

Consequently, a number of hawk neuromuscular behaviors are rather ritualized, roughly programmatic, not thought out nor reasoned. Nest building, especially the insertion and placement of sticks is one of these behaviors. As intent as the bird might have appeared in its stick-placing deliberations, its meager mind was really not paying much attention at all. The bird was merely going through the motions (seemingly like a number of students I once taught, and much like myself when I'm assigned undesirable and menial tasks). The bird got bored, so it decided to fly off with the stick and come back with it from, perhaps, another angle.

Don't read much into this. The bird thinks hard about hunting. It thinks very little about putting sticks together to make a nest. The bird really has no understanding or comprehension of what it’s doing. It just goes through the genetically programmed motions. If it looks indeliberate and unconsidered to us, it is. Don't presume that these birds have mammalian minds. The don't. They have bird brains, and those small collections of neurons work in only limited ways.

Don't make the mistake of presuming or assigning normal human thought patterns to red-tailed hawks. You can do that to your dog, who you know thinks so much like a human. Their brains are very similar to ours, in general arrangement and organization. Dogs, like us, are very social, so we can easily identify with them, even assign them very human personalities. But don't do that with the hawks. Remember, birds are in some respects merely feathered, flying modern dinosaurs. They can't and don't act or think like mammals. Don't try to make them do any of that.

I still smile in moderate frustration when I see such ritualized neuromuscular behaviors when Savanna, my adult falconry red-tail eats a provided meal on my gloved fist. She particularly likes turkey poults (young hatchlings). I have a freezer full of these and other similar hawk food delights. Savanna will step onto the poult and pull off a wing, the head, or just some general body part. Anyone who’s watched Pale Male or Lola eat up close knows the scenario. In watching the feast, the bird often grabs the food inefficiently, even missing some very obvious (to us) exposed tidbit of food.

For a bird that can so adroitly grab fleeing prey with its feet, to watch it so clumsily use its feet and beak in the rather random tearing apart of its food causes one to wonder if the bird is in good health. There is little that is delicate when a red-tail steps on to a dead prey animal and starts to rip it apart. It’s not unlike watching a two-year old try to feed himself.

So expect to see such going-through-the-motions behaviors. That’s all they are. In the end, they always work out, as crude and random as they so often appear.

Contrast those behaviors with what the bird does so expertly; that is, to fly and hunt. Nothing random or clumsy there. It’s expertise that surpasses any ballerina or professional athlete. No question marks needed.

JOHN BLAKEMAN'S SECOND LETTER, RECEIVED AROUND 7:30 ON 2/7/05, AFTER I SENT HIM THE NY TIMES ARTICLE ABOUT AVIAN BRAINS.

Marie,

You are astute. I read this information a week or so ago, and rather dismissed it for my raptors, and still do. The need for a major reconsideration of the unique organization of the avian brain, distinctly separating it from the mammalian one, is long overdue. I have no issue with that. I recall from basic ornithology class many years ago reading about how different bird brains are. The authors of the new study are correct. The old perspectives must be thrown out.

But in the larger picture, those relate primarily to tissues and structures, not to a universal, elevated bird mentality. Note that the birds used to illustrate this contention were all corvids: crows, jays, and ravens. The intellect of these birds has been noted for centuries, and the newer understandings of avian brain tissues helps to elucidate the brilliance of these birds.

Hawks however, have never been known for their intellects. And neither have most bird groups. I believe the study's authors used corvid intellect only to substantiate their more general claim that bird brains are decidedly different from mammals. If a crow is so smart, it therefore has to have a brain different from a lab mouse or rat.

I stand by the contentions of my note. In fact, I clearly stated that red-tails don't think like either humans or dogs. They think like raptors, not mammals. So, is the question a matter of degrees of intellect (as with the corvids), or is it with the very different arrangements of brain tissues? I think the greater story is the latter. And that helps explain the "un-thoughtful" behaviors people will see red-tails engage in, such as messing with a stick for six minutes, only to fly off with it and then return and leave it.

Yours is a very good question, one that I didn't address except here. Others, too, wondered, I'm sure.

Whatever the perspective, the more important understanding is that hawk watchers need to refrain from anthropomorphizing the hawks. However their brains work or are arranged, they are real bird brains, not mammal brains. That can help account for some otherwise strange hawk behaviors.

Sincerely,

John A. Blakeman