Monday, February 27, 2006

Dr. Vector's Web Sausage

A meaty casing stuffed with cool stuff.


PURE COMEDY

Beware of bread.
http://www.eskimo.com/~spban/bread.html

The best of Jimmy Kimmel's unnecessary censorship.
http://www.break.com/index/kimmelcensor.html

Hell o'clock news, courtesy of Tenacious D.
http://tenaciousdmovie.com/


GADGETS

Virtual keyboard for PDAs, phones, etc.
http://www.virtual-laser-keyboard.com/

Another reason to junk your keyboard: the computer interface of the future.
http://www.eng.biu.ac.il/~noytza/touch.html

Flying lawnmower.
http://3do.jediknight.net/dcm/cross.htm

Just what it says: RoboDump.
http://triggur.org/robodump/

Buy this. It's loads of fun and nearly indestructible, with a soft foam nose that won't wreak destruction on anything else, either. Mine got carried around the beach by a friend's dog and despite many fin punctures it flies just fine. The integral slingshot band is maybe the best thing anyone ever put in a cheap toy. Ultimate bang for your buck.
http://www.rhinotoys.com/product_skyblaster.shtml


STAR WARS, LEGO, STAR WARS AND LEGO TOGETHER

New TIE fighters.
http://www.starshipmodeler.com/starwars/tie_challenge.htm

Spoofs of those "Incredibel Cross-Sections" books.
http://3do.jediknight.net/dcm/cross.htm

Big LEGO church. Like, frighteningly large.
http://www.amyhughes.org/lego/church/index.html

Pimped-out LEGO Star Wars.
http://www.reasonablyclever.com/lego/bling/index.html

Friday, February 24, 2006

Quantum dissertating

Scientists at the University of Illinois at Urbana-Champaign have used a quantum computer to solve an algorithm by, er, not running the algorithm. They used something called 'counterfactual computation' to infer the nature of the solution without actually determining it.

Now, this probably sounds like a lot of mystical mumbo-jumbo to you slope-browed subhumans, but it makes perfect sense to me.

I'm writing my dissertation using a related process that I call 'counterproductive productivity'. For example, today I spent a few hours surfing the web and then watched Olympic figure skating. To the untrained eye of the ignorant layman, it might look like I didn't get anything done. However, I spend pretty much every day the same way I spent this one (except most of the time I'm stuck with Law and Order: SVU reruns instead of scantily-clad chicks on ice), and my dissertation is slowly getting done. In fact, I've written about 50 pages of it since the beginning of the year. Now, if we divide the number of pages written by the number of days in the year so far--54--we see that I'm producing about a page a day.

So where's today's page? you may wonder. Well, get used to disappointment, because I can't tell you. It is well known in quantum mechanics that one cannot know both the velocity and the position of a particle--that's Heisenberg's Uncertainty Principle, bitches. Similarly, in quantum dissertating one cannot know both the velocity and position of one's dissertation. I already know the velocity--one page a day--so it is impossible for me to determine the position!

In view of this astounding fact of physical reality, I think I'd better get back to the TV. After all, I've got a dissertation to write.

Wednesday, February 22, 2006

Science Communication, or How to Shoot Yourself In the Foot

One of my labmates, Randy Irmis, sent around a couple of interesting links on science communication. The first is a list of seven rules from a NOVA producer. The second is a list of things scientists can do to teach evolution more effectively, and the follow-up comments are even more illuminating than the list.

From a science communication standpoint, the most valuable experiences I've had were teaching a high school science class through the GK-12 program, and being involved with the Big Dinos Return exhibit at the Lawrence Hall of Science. Here's what I learned:

Freshmen may sit quietly while you draw a cladogram on the board, because they have to, but high school students will not, and neither will the general public. My "How to carve your Thanksgiving dinosaur" talk at LHS was fairly disastrous. Even after months of working on signage for the exhibit, I had completely misjudged the approach to take. The 'lecture' portion, which felt quite streamlined to me, quickly whittled my audience down from about 50 to about 12. Things turned around when I started showing people bones and how they go together. In retrospect, I should have started by showing the audience some cool anatomy and letting them ask questions, and then used their questions as a very gentle springboard to talking about the science. I don't think I would have had to dumb it down, I just think I approached it bass-ackwards. It's the accessible stuff, like bones and fossils, that makes people care about the science, not vice versa. Heck, I became a scientist so I could play with the cool stuff all the time.

Also, the NOVA guy is exactly right: people like to figure stuff out for themselves. Imagine if mystery writers gave away the whodunnit on page 10 and then spent the next 200 pages explaining how cool the crime was. I think that's a big problem in science communication and education. As a teacher, I am a compulsive sharer: biology is so cool to me that I can hardly help jumping right to the conclusion. But looking back, my most memorable educational experiences are of figuring things out on my own, because my teachers were smart enough to prepare the way without giving up the ending. It's hard to make up lessons that go that way, but maybe I've had my head on wrong. Maybe the strategy outlined above, of showing people the goodies and letting their curiosity draw them onward, is so reliable that I should be counting on it, not worrying about how to plan it.

The best thing we have going for us is that people are curious. They're practically desperate for news, and the Discovery Channel (a.k.a. the Bigfoot Channel*) isn't getting the job done. Over the past year I have had many conversations with strangers, and inevitably when they hear that my work relates dinosaurs and birds, all other topics are dead. They want to know all about it. I get the impression that I could walk into a mall, announce "I am a paleontologist", and spend an indefinite amount of time answering questions.

*One of the few useful services of the Discovery Channel is serving as the US outlet for BBC documentaries, which generally whip the pants off of anything homegrown. See Walking With Dinosaurs/Beasts/Cavemen, Blue Planet, and Journey to the Planets/Space Odyssey.

One thing that really disturbs me is the frequent lament on the part of scientists that the public is stupid. It bothers me for two big reasons. The first is that I don't think it's true at all. I've had engaging conversations with laypeople from 7 to 70, and in general people are very good about asking questions (curiosity again) and following chains of inference, IF they're presented accessibly. It's not that there aren't willfully stupid and combative people out there in the world. But they're comparatively rare, and I've had the good fortune not to run into any. In general, I think the "people are stupid" complaint is really code for "I'm so ridiculously out of touch that I'm basically incapable of meaningful human communication, and I'm not willing to change". Who's stupid now?

The second reason it bothers me is that it's godawful PR. If the "people are stupid" meme is reaching me, then it's reaching a lot of people, too. And if they hear that, decide that scientists are a bunch of pampered, arrogant elitists, and tune out, who can blame them? Anyone who complains about the public being stupid is a pampered, arrogant elitist.

'Nuff said.

Saturday, February 18, 2006

Oklahoma's big cat

Darren Naish's post on British big cats brought to mind one of my favorite animals from Oklahoma: the mountain lion.

Huh? Mountain lions in Oklahoma?

Yup. The mountain lions are there, although you can live there your whole life without ever becoming aware of them. My only Oklahoma mountian lion encounter was finding tracks down at the local creek when I was in my early teens. The tracks were big, clear, and unmistakably feline. I knew that there were bobcats around, but the tracks were way too big to be those of a bobcat, and I didn't know that there were any mountain lions in Oklahoma. I thought I was going crazy, but Mom said that people living in the area (Garfield County in north-central Oklahoma) reported seeing them with fair regularity, but that the local wildlife guys would never confirm that they were present.

I learned more about Oklahoma mountain lions when I was going to OU and living in Norman, right in the middle of the state. Norman is in Cleveland County, which is part of the Greater Oklahoma City Statistical Area. People like to joke about Oklahoma being the sticks, and with a total population of just over 200,000, Cleveland County is hardly the Bay Area. But people are pretty thick on the ground--about 373 humans per square mile, on average. Of course, that average is misleading, but not as much as you might think. Half of the people in the county live in Norman, which occupies just over a third of the county's area (190/550 square miles). That still leaves 100,000 people in the rest of the county.

Why am I boring you with all of this demographic and geographic detail? Because according to a friend in the Oklahoma Department of Wildlife Conservation, there are six mountain lions living in Cleveland County. Six.

This has obvious implications for the "reality" of Alien Big Cats (ABCs) in England and other places--or rather, for our perception of their reality. From the perspective of the average Cleveland County resident, mountain lions are crytozoological phenomena. ABC skeptics who don't think that big cats can survive in, say, the English countryside without their presence becoming widely known need to consider that that's exactly what mountain lions are doing in one of the most densely populated counties in Oklahoma.

My only encounter with a mountain lion in the wild was at Fort Chaffee in northwestern Arkansas, when I was on a beetle survey. One zipped across the road as my partner and I were driving up to one of our transects. But before I tell you about that, I'll tell you about my bobcat encounter.

When I was a kid my brothers and I used to go on long walks, and since we lived in the country, that meant walking along dirt roads. Most of the land in Oklahoma is given over to cow pastures and wheat fields, including the fields around our place. The diversity and density of wildlife that we saw on a regular basis would boggle someone raised in a city. There were two coyote dens nearby, about a quarter mile to the east and west of the house. We saw deer, pheasants, raccoons, opossums, skunks, and red-tailed hawks often enough that they hardly deserved comment, unless the deer came right up into the yard, as they occasionally did. Foxes and golden eagles, those we got excited about.

Anyway, Todd and I were on a walk and we heard a critter rustling around in the tall grass in the ditch next to the road. Naturally we wanted to flush it out so we could see what it was, so we picked up a couple of rocks off the road and tossed them into the grass where the sound was coming from. The movement stopped. I tossed one more rock, and then we heard the loudest, most devilish, most pissed-off hiss I have ever heard in my life. It was terrifying. We backed up to the other side of the road and walked off as quickly and quietly as dignity would allow.

I assume that the thing that hissed at us was a bobcat. We never actually saw it, so for all I know it might have been an especially cantankerous raccoon, or some kind of brain-sucking alien. But bobcats were known to be about and it hissed like a cat, and it didn't back down or run away, which also tends to make me think it was a cat. But the bobcat-ness or otherwise of the mystery hisser is not the point. The point is that an animal that can hide its entire body in 18 inches of grass doesn't sound very scary, until you're standing eight feet from it and it's hissing at you. Suddenly you are devastatingly aware, as you never have been, of just how slow, defenseless, and generally lame humans are.

Multiply that acute awareness of your vulnerability by about a thousand, and you have some idea of what it's like to walk a 180-meter transect through the woods where you just saw a mountain lion. Up until then, my partner and I had thought nothing about splitting up and each checking half the traps, which would put us well out of sight and often almost out of voice range of each other. Not after that day! When we got back to base we found out that two other teams had also seen mountain lions that day, and they were close enough in time and distant enough in space that they had to be three different cats.

Mom and Dad still live in the house in the country where I did most of my growing up. Unless the weather is downright beastly, Mom gets out and walks about half a mile every evening. Last fall she had a mountain lion encounter of her own, and it puts mine to shame. When she was just a couple hundred yards from the house, a mountain lion slowly paced across the road in front of her, about halfway to the house. When it got across the road, it sat down looked right at her. Naturally she stopped, and she and the mountain lion just stared at each other across less than the length of a football field for several minutes. Eventually the lion lost interest and padded off into the field, and Mom got home in one piece. She said it was the most frightening experience of her life.

Oh, one other parallel between Oklahoma mountain lions and British big cats: silence or derision on the part of the authorities. It's not like the ODWC doesn't admit that mountain lions are around, but from reading their
page on the subject you could be forgiven if you got the impression that there were maybe two or three mountain lions out in western Oklahoma and the rest were anomalies that had wandered in from neighboring states. I found this statement especially curious: "Agency personnel have not conducted population surveys or assessed habitat availability, making it impossible to issue clear statements about the abundance of wild mountain lions." In-ter-est-ing. Why would ODWC personnel want avoid making clear statements about how mountain lions are around? Part of it is probably the same reason that British authorities don't want to admit that panthers and so on are padding around the English countryside: government officials have nothing to gain and plenty to lose by admitting that big cats are in your neighborhood. But I think the ODWC's relative silence is probably a protective measure, as well--for the mountain lions. Right now Oklahoma's mountain lions seem to be coexisting with humans with a minimum of noise or trouble. If they are nabbing a calf here and there, no one seems to be raising any hell about it. Raising public awareness of mountain lions is bad for everybody. Ranchers will demand that the ODWC census the cats, and probably track them as well, and maybe even relocate them or cull them. That's harrassment the cats, and the ODWC personnel, just don't need. And I'm sure those f'ing retards on the evening news would whip up a maelstrom of mountain lion panic faster than you can say "yellow journalism". Mountain lions have survived in Oklahoma by being invisible, and I'm glad the ODWC is letting them stay that way, regardless of their motives or the official position.

There's one other thing I keep thinking about. We've got a mounted T. rex skeleton in the Valley Life Sciences Building at Berkeley. Everyone who works in the building walks past it at least twice a day. It's easy to get blase about it. But I can't help thinking about the bobcat--or bobcat-sized mammal--that scared the living piss out of me, and about how desperately vulnerable I felt being on the ground where I'd just seen a mountain lion. I think if any of us saw a T. rex in real life, we'd be literally paralyzed with fear. It would be so frightening that it would transcent the category. I suppose infantrymen who have been attacked by tanks have some idea of what it would be like to run into a T. rex, but I doubt if the rest of us have any idea at all.

So, yes, this post started with mountain lions and ended with tyrannosaurs. I told you I had a thing for them. And c'mon--don't tell me you never think about this stuff, you big faker.

Thursday, February 16, 2006

Dr. Vector wanes poetic

I wrote this sometime in 1996 or 1997.


MIDNIGHT IN THE MUSEUM

Midnight in the museum
In the silent resonance
Of empty space
The great xylophone skeletons
Play the lonely strains of time
Like cathedral organs
Heralding the ends of ages

Time rushes on
The final predator
Implacable
Like Dinichthys
Cruising the crinoid beds
Sounding one note:
Everything dies
Change
Smashes all
On the rails of eons
Carnivores and civilizations
Long of tooth, weak of spirit
Wracked by rot and riot
Collapse
Their carcasses play host
To new generations
That strip the drying flesh
And flaunt their youth
Beneath the Philistine stars
That warmed the comets
Long before the phoenix-fusion birth
Of brash young Sol

I hear the distant call
The silent whistle screaming
Of my genes
Seeking always
To jump this fragile ship of life
And flee down the generations
Until I am lost
Expended
Forgotten
The tyrant kings smile knowingly--
"You too shall pass"--
And continue their stately voyage
Into eternity

The circle closes
The orbit complete
And morning spreads her wings
To the far horizon
I do not fear the dawn
Or the age to come
For I have basked
On desert sands
Drinking life like heat
And felt the mighty Tethys
Washing over my feet

A decade of dreams come true

Amazingly, improbably, it's 2006. A signal year for me. In the spring of 1996 I met with my faculty advisor at OU, Trish Schwagmeyer. I asked her what I could be doing to make myself more attractive to grad schools. She said go find a faculty member you like and do an independent study. I knew Rich from my high school mentorship (1992-1993), but since arriving at OU I'd avoided the museum, in part to satisfy myself that I didn't really want to be an aeronautical engineer or an English teacher (nix to both). So I walked down to Rich's office, dropped my butt in a chair, and asked for an independent study project. He said, "Well, we've got these big bones from Atoka..."

I got off to a slow start. I tracked down and photocopied a bunch of papers in the summer of 1996, but I didn't read them. I started slogging through the literature that fall, but nothing made sense to me. Then in about October I woke one morning with a sudden fit of inspiration, grabbed my 'sauropod notebook', and drew a sauropod vertebra. Then I painstakingly copied all of the lamina names from Janensch (1950), judging that 'hinter centroparapophysealeiste' probably meant 'posterior centroparapophyseal lamina'. That was my awakening. From then on, the papers started making sense, and the insights started coming. By the end of the semester I knew that OMNH 53062 was something new. In March of 1997 I went to D.C. and satisfied myself that it wasn't Pleurocoelus. That summer I drove around the West visiting museums, met Brooks Britt, and was told to get myself to a CT scanner.

And now here I am. Looking back, it is like watching a snowball roll downhill and become an avalanche. It's scary, because so many accidental, incidental contacts shaped my course. What if I'd zigged instead of zagging? I'd never had an especial interest in sauropods. I'd always been a tyrannosaur and ceratopsian man. But I think I fell in love with OMNH 53062 and all things connected to it. I used to daydream when I was driving and watch herds of brachiosaurs wandering the Oklahoma plains. I remember getting tears in my eyes at the thought that I'd never get to see one in real life. Time has taken the edge off of those feelings, but it hasn't erased them.

Here's hoping that you find what you love.

Return of the Unintentionally Homoerotic King

Put in your Return of the King video or DVD, theatrical release or extended edition (it works either way), push 'play', and then look away or shut your eyes and just listen to the first few minutes. This is what you'll hear:

"Give it to me."
"Why should I?"
"It's my birthday and I wants it."

Then a few minutes of wet bodies slapping together, with much manly grunting. Towards the end a visceral throbbing sound overwhelms everthing else. Silence descends.

Finally: "My precioussssssssss."

Still more Chelydran awesomeness

The second promised snapping turtle post, transcribed from an e-mail exchange on Feb. 12, and filled with bizarre feeding behaviors, including ichthyological mucophagy. Enjoy.

I have some more snapping turtles stories to share with you.

Like box turtles and kinosternids, snappers have musk glands around the edges of their carapaces. Normally the musk they emit is a thin, clear oil that smells pretty much like dead turtle. Since the turtle is usually wet, the oil isn't visibly noticeable. Suddenly the turtle just smells like it's dead. But Julian Hilliard and I once caught an old snapper that hadn't been molested in a long time. We surmised that that was so because when I picked it up, the stuff that came out of the musk glands looked like orange toothpaste, and smelled like a landfill full of dirty diapers and sweaty jock straps.

On the gluttony of snappers. When my little Chelydra, Maverick, was about 5 inches in carapace length, I would go to the OU duck pond and catch mosquitofish (Poecilia) to feed him. In the winter the mosquitofish were so desperate for organic sustenance that I could hock a loogie into the pond and within thirty seconds there would be hundreds of fish fighting to eat my snot. I just dipped them up with an ordinary aquarium net, one of the square green ones. I once got 67 fish in a single pass, and just over 300 in six passes. They're invasive and they're pushing out native minnows, so I never felt bad about doing it. I'd take 'em home and dump 'em in the tank and Maverick would go to town. He'd come up below them as they schooled near the surface and get half a dozen at a time, even as small as he was. Even when his carapace was only 5-6 inches, he would easily eat 60-70 mosquitofish on the first day. He'd eat until his stomach was full and then start stuffing them into his esophagus. When the epic murder glut was over, he'd sit on the bottom with all four limbs, tail, and neck maximally extended; I suppose there was simply no more room in his shell for anything besides stomach. You could tell when he'd pack his esophagus full because when he turned his head to the side the back 2/3 of his neck would be held stiff by his distended esophagus. It was a disgusting spectacle, and one that I enjoyed orchestrating and watching.

After the initial bloodbath, Mav would sit on the bottom for 4-5 days and digest. After that he'd pick off the rest of the fish at a rate of 10-20 per day. The dieoff was exponential, not linear; as the number of fish got small, it was easier for them to evade him, and I'm convinced that some of them got smarter. When I couldn't get mosquitofish, I'd give him feeder goldfish 30 or 60 at a time (they were 10c apiece at the time). There would always be one or two survivors that he would never catch, no matter how long I left them in...until the next time I added fish. The survivors seemed to get stupid again when they were back in a school, and they'd get nailed, and there would be a new survivor at the end of it all.

I also witnessed some pretty interesting feeding behaviors from Mav. If you've never seen a snapper in action, their underwater strike is pretty cool. They thrust their heads forward so fast that your eye can't really track it; the head just disappears in one place and reappears in another. At the same time, they use their hyoid apparatus to balloon up the pharynx, which draws in vast amounts of water. Between the strike and pharyngeal suction, Mav could really grab the fish. Sometimes he would be right behind a fish on the bottom of the tank, and the fish would simply disappear. I'm just guessing here, but I'd say the entire strike could take less than a tenth of a second. Sometimes he would do one slow enough that you could see what was actually happening. Those took about a quarter of a second, and it really felt like watching slow motion if you were used to watching him eat. He only used the slow strikes when he was really full and lazy, or to snap up the leftover bits after some serious predator theater.

One behavior I never saw referenced in the literature: Mav would open his jaws fractionally, tilt his head to put one side of his mouth next to the bottom, and use the hyoid balloon technique to vacuum up uneaten bits of fish food.

For a turtle, Mav was pretty darn smart. When I first got the big tank (44 gallons), Julian and I would go seine the local creeks and split the catch (Jules had a caiman at the time). I had all kinds of stuff in my tank: bullhead catfish, several varieties of sunfish and crappie, even a little smallmouth bass. As Mav got bigger, they all disappeared, one by one (this was before the giant Poecilia dumps). The last of the big fish to go was one of the bullheads. At 9 inches long, it was about the same mass as Mav, and it was canny. No matter what hour or angle Mav chose for his approach, no matter how slowly he sidled up, the bullhead would always jet at the last minute. But after about 3 months of pursuit, Mav finally got him. I had a big log angled across the tank so he had something to hang on when he was resting near the surface. He learned how to dangle upside down from the log, hanging on with his hind legs, and strike straight down at the bullhead's back. On the first attempt he put a neat triangular notch in the bullhead's dorsal fin, but on the second try he got the epaxial muscle, and that was the end of it. Once he had his jaws in something he'd retract his neck to pull the prey to him (or to pull himself to the prey, depending on who was stronger). Once the prey was up close, he could use his forefoot claws to rip it to shreds. It wasn't always fast, and it was rarely pretty, but it sure was effective.

I had a 300 gallon/hour filter on the tank, by the way. It would have been massive overkill if I'd just had fish. With Mav, I think it was just what I needed.

I know Mav was a male because when I picked him up he would hiss, snap, and (incongruously) stick out his penis. It was purple and about 2 inches long and just over a quarter of an inch wide. That's when his carapace was about 6 inches. I let him go shortly thereafter. He was just getting too big. Normally it takes a hatchling snapper 6 or 7 years to get that big, but Mav did it in two. Of course, he was warm all year long and had all the food he could handle...

More on the indestructibility of snappers. One evening I was driving to Julian's place for a barbeque and I saw a big snapper smashed on the road near the OU duck pond. It was off on the shoulder, but I could see red flesh in the middle of its shell, so I knew it was toast. When I got to Julian's, we decided to go back and see if we could get the head.

Whew. The next part isn't pretty. The snapper was a monster. I measured the carapace: 15 inches. It had been run over on its right side, and that half of the carapace was caved in. I could see the lungs, liver, and intestines exposed through the hole in the shell. It gets worse. The turtle had been hit in the middle of the road, and managed to drag itself more than 15 feet from the center median to the shoulder; the path was marked with blood and fluid. And here's the worst bit: when we got there, the turtle had its head up and was looking around. It was not just waving it's head in some kind of stupor. It was alert. That that hideously wounded animal was still alive was the most sickening thing I'd seen in my life to that point (and may still be).

Well, we had to put it out of its misery. I don't know how long that poor animal had been there since the collision, but we were going to give it a swift, merciful death. Trouble is, killing a snapper is no easy task. First we tried to crush its neck with an axe handle. No luck. Keep in mind, this was two guys, fresh back from hucking 100-lb bags of matrix around in the field, and we couldn't break the turtle's neck. Unfortunately, we were just working with what we had on us, and the axe handle in the bed of Julian's truck didn't have a head on it. Then we tried to saw through its neck with the saw on my Swiss Army knife. That saw is no joke. I had used it for cutting holes in sheetrock and trimming the edges of plaster jackets. It was sharp as hell, but I could not get through the skin on that snapper's neck. It was like trying to saw through, I don't know, a Kevlar boot, maybe. I couldn't even draw blood. In the end, Julian drove back to his house and got a hatchet, and we chopped the turtle's head off. The severed head continued to move its eyes and snap at us for five minutes, I shit you not. (We pithed it after a few minutes.) Julian still has the skull. It's four inches across at the widest point.

I got my own snapper skull later that summer, and learned a little more about the toughness of snapper skin. I was cleaning out a warehouse at OU and found a trash bag with a mummified snapper in it. I guess someone had found a dead one and collected it, and then just forgotten about it. Bugs must have gotten to it at some point, because the flesh and guts were mostly gone. It was mainly mummified skin and shell. I decided to clean it up using bacterial maceration. I put the crispy critter in a 5 gallon bucket, filled it with water, covered it with 2 boards and a cinder block to keep the opossums and raccoons out, and let it sit on my back porch in the 100+ F Oklahoma heat for two weeks. At the end of that time I had a bucket of thin turtle soup with greasy but otherwise clean bones at the bottom. Unfortunately the shell fell apart--snapper shells are solid enough in life, but take off the soft tissue and they go to pieces, just like trionychids. I degreased the bones and still have most of them, although I gave the skull away (but not before I'd gotten a better one). One cool discovery was that the spikes on the tail consist of bony cores under a keratin sheath. Most of the spikes were floating in connective tissue, but the most proximal one had gotten so large that it had contacted the neural spine of the adjacent caudal vertebra and fused to it. I could probably take some pictures for you if you're interested...

Oh, on the ruggedness of snapper skin. I forgot to mention that after the two weeks of maceration, the bones were clean and the shell had fallen apart, but the skin was still more or less intact. I fished it out and it could be torn, but it would not fall apart on its own. That's after a certain amount of decomposition, several years of dessication, and two weeks of maceration in 100+ temperatures. So the lesson is that snapper skin may look and feel soft, but it is nearly impenetrable.

Finally, I kept a Platysternon (Southeast Asian Big-Headed Turtle) for most of the past three years. I think the most recent phylogenetic analyses posit Platysternon as an aberrant batagurid or batagurid ally. That makes sense to me. The similarities to the chelydrids are entirely superficial. Platysternon has a flat, unserrated shell, a short neck, a fairly flat plastron, skin without the numerous spikes, fringes, and tubercles of chelydrids, and a prehensile, spikeless tail. I'd read about the tail prehensility, and about Platysternon supposedly vocalizing. It's all true. My turtle, Carl Hungus, had remarkable ability to control the tail and to exert force through it. Put him in a five-gallon bucket and he'd prop himself up on his tail alone, and keep pushing with progressively more distal segments, until he could hook a forelimb over the edge and pull himself out. That's a turtle with a seven-inch carapace. Platysternon's head is shaped very differently from Chelydra's, and the top of the head is covered with a single large, rigid scale, very unlike the soft leathery skin on the heads of snappers.

Oh, the vocalizing. Sorry, I'm pooped and frankly even I'm getting sick of writing about turtles. Yeah, Platysternon vocalizes, both in and out of the water. Out of water it comes out as a scream. I've heard tortoises wheeze, but Carl's screams could be mistaken for a baby's. Once when I was giving him a checkup he screamed and Vicki came out of the bedroom to see if it was London. In the water, Carl would growl. It sounded like someone sliding furniture across a wood floor. It was just an incredible amount of noise to come out of an animal that is basically the size of a really big sandwich.

There you go. If you're really nice, maybe someday I'll write about my experiences keeping box and musk turtles.

Dr. Vector drops some science

Following the recommendation of Mike Taylor and the inspirational example of Darren Naish, both limey bastards from the other side of the pond, I will post at least two entries on snapping turtles. This is the first. Try not to crap your pants with excitement.

Transcribed from an e-mail conversation on Feb. 10:

Any evidence for giant snapping turtles eating hapless swimmers? Hmm. Seriously, are you familiar with the "sport" of noodling for catfish, in which one sticks a sometimes gloved but usually bare hand up under overhanging banks of southern creeks and ponds in the hopes that a giant channel or flathead catfish will bite the hand and thereby be captured? Since the noodlers are running completely blind, and since the hollows under overhanging banks are favorite haunts for both species of snapping turtle, people occasionally get a turtle instead, and the injuries can be spectacular.

Hmm. There ought to be some web resources on this.

Noodling described; photos debunked.
http://www.snopes.com/photos/animals/noodling.asp

Noodling as an extreme sport.
http://www.cabelas.com/information/cabelas-field-guides/Catfish-Techniques/Noodling-for-Catfish-The-Ultimate-Thrill-in-Fishing.html

Not noodling related, but a testament to the dangerousness of snapping turtles.
http://www.ananova.com/news/story/sm_1438724.html

I tried to find picture of people who have had fingers severed by snapping turtles. No luck so far in my exhaustive ten-minute search. There are pictures in Peter Prichard's book on the alligator snapping turtle.

I have seen and handled many common snapping turtles, and I can tell you that they are meanest creatures on the planet, and that legends of their ferocity usually come nowhere near the truth. I raised one from a hatchling to sexual maturity (carapace length of about 8 inches) and when it was younger it would frequently kill fish that were bigger than it was. The speed and power of the bite and the turtles' willingness to use it on anything that moves could hardly be exaggerated. They are my favorite living tetrapods.

That's the common snapper (Chelydra serpentina), which only gets up to a poxy 76 pounds in the wild (a National Geographic story on snappers from the late '90s has a photo of that turtle being weighed), although captive specimens have topped 90 lbs. In the 1800s it was evidently fairly common to put a captured snapper in a hogshead barrel and fatten it up for several months on table scraps. They're incredibly hardy and almost impossible to kill. I have seen big (~18 inch carapace) snappers crawling around in the creek near my cousins' house in Elma, Manitoba; I have pulled snappers out of cold, cobble-bottomed trout streams in the Ozarks; and there is a verified record of a snapper sunning itself on a frosty bank in January when the air temperature was 25 degrees F.

The alligator snapper (Macroclemys temmincki) is whole 'nuther ball of wax. Numerous verified reports of specimens over 200 lbs and with carapace lengths approaching 3 feet. Unsubstantiated reports of specimens up to 400 lbs and with carapace lengths approaching 4 feet. Any run-of-the-mill alligator snapper skull will be 8 inches across the back end, and I think the world record skull was more than 10 inches wide.

In the New World snappers range from Ecuador to Canada; the ones I saw at my cousins' place were very near the northern limit for the species. There used to be snappers in Eurasia, but they bit it back in the Pliocene. What would make snappers go extinct I can't imagine. Anyway, you guys probably have some feral populations now, since snappers can survive just about anywhere, live practically forever, have no natural enemies once they're past the hatchling stage, and can toss out up to 80 eggs a year. People are so afraid of snappers becoming established in California that it's illegal to even bring them into the state.

Um.

I'll stop now.