Wednesday, November 21, 2007

It Was About LIght But Now It's Toes

It's snowing. Therefore I opened the door and took a photograph of the snow. It's night, the flash went off and this is what I got. Now the little white specks look like snow. The colors are no doubt created by the refraction of light but just exactly the process creating the fireworks type circles, I wasn't sure. Something to do with snow "sparkle" or light flare, the speed of light, and shutter speed. That was what the blog was going to be about tonight.

Something to do with snow "sparkle" or light flare, the speed of light, the flash on the camera, and "shutter speed". The blog was going to be about the interaction of those factors in the creation of those images. And then as I always want a bird, and I had one today who kept dipping her head behind the suet when I clicked the camera so I was going to quiz you readers about exactly what bird it was by her tail and feet.

But due to the vagaries of Blogger and my equipment I have to put the photographs into the blog starting with the one on the bottom and going up. That is where the problem began. So we're going directly to the bird. If anyone would like to research the process that created the above photos, go for it. I got hung up tonight looking into bird feet.

Now to the bird.

Can you tell what bird this is by her tail? If not the species, how about the family?

How about her foot? Check out the position of the toes. (Hint, hint.)
How about this one? I thought it would be the give away until I zoomed in. Then I thought, wait, is that a zygodactyl foot? Did something else sneak back behind the suet when I wasn't looking .
No, the tail is the right tail. Is this species an exception? How could I have missed that? Off I went to Google and as sometimes happens, the odyssey began.
I typed in Woodpecker (Did you have that much?) and zygodactyl , hit search and began browsing. My, my, they've just discovered a really scrunched fossil, indistinguishable really, except that it's the first obviously zygodactyl fossil in the Epocene period. Very interesting.
Generally in simple material on Woodpeckers, after their wood banging is discussed, their toes come up. It's said that they're zygodactyl, two toes in front and two toes in back, except currently on the Cornell site. In their notes on woodpeckers, zygodactyl is defined as two toes in front and one in back. WHAT! I began to think I was having a bout of senility.
Back to the Google hits--
COME ON? An abstract from the American Museum of Natural History, 1959, by Walter Joseph Bock, which began, "The scansorial foot of the woodpeckers is not a zygodactyl foot, as commonly believed, but a quite different structure--the ectropodactyl foot...(and why had I been taught all this time that the foot was zygodactyl if this guy zapped the concept in 1959? And just what is a an ECTROPODACTYL foot?)...the toes of the climbing woodpecker are arranged as follows: toes two and three point forward, the fourth toe is thrust out to the lateral side at right angles to the fore toes, and the hallux usually lies beneath the distal end of ...."
Never mind, look at the photograph above. THAT is what he's tallking about. Two toes straight up, one going to the side and the fourth isn't doing anything. Ectropedactyl ! It looks ectropedactyl. Why does everyone still say woodpeckers are zygodactyl then?
Forget Google. I pull out The Audubon Society's The Sibley Guide to Bird Life and Behavior. Besides by this point I'd run across the fossil abstract on JOSTER that said "The permanantly yoke-toed birds include the heterodactyl (2nd digit reversed)trogons(Trogones) and the zygodactyl (4th digit reversed)woodpeckers..." So I have to refresh my memory as to who the Trogenes are anyway. And what about that 2nd and 4th digit thing?
I start thinking of "yoke-toed". Ah, right. Two front toes front, two back toes back, not even a slight lateral. The position in which Silver, when escaping from his play area on top of his cage to the floor, holds his feet while doing a controlled slide down the legs of his cage. He holds his feet in circles, two front toes curled toward his curled rear toes, then using his beak as a brake he briskly slides down the round legs of the stand and gambols off to get into trouble.
Isn't a yoke toed bird and a second yoke toed bird the same? Evidentally not.
See how this grows. I told you it was an odessy.

It all became clear because as always with everything in biology, as it's an attempt to catagorize life, and life isn't really all that catagorizeable there are exceptions and equivications.

Yes, Woodpeckers are still considered zygodactyl no matter what Mr. Bock says, two toes front and two two back, well except the Three Toed Woodpecker, at least they make it clear by it's name, and the Black-backed where it isn't obvious by it's name, BUT the climbing woodpeckers just hold their feet in a ectropodactyl position a lot of the time when they're climbing. They aren't really ectropodactyl, they just look that way. Sheesh. Kingfishers are ectropodactyl. The have two toes front, in fact partially fused, and the other two toes come out at sharp right angles laterally. Extremely strange looking and they say they aren't really good for much except perching. But on what?

As I hadn't had quite enough yet, curiosity can be exhausting, I crawled on to heterodactyl and Trogones and their second digit. In a nutshell, Trogones are pantropical (no wonder they'd slipped my mind) and instead of the outer toe rotating back like a zygodactyl bird, their inner of the "three front toes" rotates back during chickhood. Got it?

By the way, the woodpecker obscured by the suet is the Downy that showed her face on the blog a few days ago.

And now for the Audubonesque Cottontail---

In Audubon's paintings he would sometimes paint the same individual animal or bird several times in a single painting in order to show the "movement" of certain behavior. Okay, his didn't overlap, but here is the same idea. Bunny chewing birdseed and watching the snow juxtaposed with Bunny alert and erect when she noticed possible danger.

And it had nothing to do with feet...

Donegal Browne

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