Sunday, March 29, 2009

Giving Back

From Science, March 6, 2009, cover image. Reprinted with permission from AAAS.

Our voyageuring trip in the Algonquin Provincial Park, Ontario, was one of the last true adventure vacations Heather and I have managed to swing [1]: the better part of two weeks on our own [2], without resupply, paddling and portaging our way across a vast system of lakes that differed from each other in stunning ways. One portage away from a brown-water lake thick with reeds, waterfowl, and the occasional, terrifyingly close bull moose, we would encounter one that seemed identical from the water level up: but deep, with a bottom strewn with rectangular rocks that you could almost touch. Then you’d look back at the guidebook, and find out those rocks were boulders, a hundred feet below you, made visible and hauntingly close by absolutely glass-clear water.

It was a damned fine trip, but for one or two very early pieces of misfortune.

We had decided — wisely, it turned out — to take a water taxi to the longest portage available from our entry lake. It accomplished several things, among them being it got us away from a motorboat-legal area in minimal time. It also put a mile-and-a-half carry of a 17-foot canoe and two really heavy dry bags behind us immediately, which seemed the best way to buy solitude as quickly as possible.

As I said, it was a wise decision, though it didn’t exactly go as planned. First, the moment I stepped off the water taxi, a hornet tagged me on a Tevaed f00t (not, at that moment, treading the jeweled thrones of the Earth). It wasn’t just the pain that had me cursing — a few seconds later I’d have had my heavy backpacking boots on, and the little bastard couldn’t have gotten me in such a critical body part. Heather pulled out the Sawyer Extractor [3], got my paw bandaged up, and I pulled on the boots and just cowboyed up.

Well, next thing was that, trying to lift the 17-footer on my own, I immediately broke the piece-of-junk yoke. That, though, turned out to be good luck in disguise: we realized that the unusual top-of-the-frame cargo extensions on our JanSport pack frames actually were a perfect shelf on which to balance a canoe. Not only could we ferry the dry bags easily, by attaching them to the frames as we’d planned, but the canoe carry itself proved easy. We had to do the portage in two goes, but then we’d been expecting to do that anyway.

I don’t remember which part of the three-legged trip it was, but I do vividly remember the sight of the woman standing at the bottom of a downhill stretch of trail, waiting with a certain tenseness as Lilly led us over the crest. Lilly had topped the hill first, seen the woman, and then come back to tell us about it.

When she saw us, the woman relaxed visibly. She later admitted, “I thought she was a wolf.”

Now, if you’re going to encounter a 73-pound she-wolf on a trail, Algonquin is a pretty logical place for it to happen. They most certainly do have wolves, whom we heard just about nightly — or at least, when the loons would shut the frack up. And I admit that there’s something unmistakably wolf-like about an uncharacteristically [4] quiet, self-possessed, mostly black German shepherd with a dark face.

Heather pretty much summed it up, though, in her unique, kill-a-man-at-20-paces-with-her-sarcasm way, when she said, “Very few of the wolves around here wear red backpacks.”

Both the woman’s error and the mythical black wolf that lurks in our collective unconscious may be doubly ironic: black color is rare among wolves, and according to a report in the March 6 Science by Tovi Anderson and a cast of characters from Stanford and a bunch of other places, it may not be “natural” to wolves (or at least, those in North America) at all.

The researchers analyzed the DNA sequence of the K locus, which causes black color in wolves, in individuals on both sides of the tundra/boreal forest divide in northwest Canada, and compared those data with dog sequences. They found out that, when you look at polymorphisms in the DNA — essentially, mutations that build up over time — for either dogs alone or dogs and wolves together, enough changes have racked up in the gene to account for the black-color mutation being nearly 50,000 years old. [5] Which is provocative, because that starts to bump up against a couple of very interesting dates: The Great Leap Forward, when among many other things human art jumped from crude representation to works like the achingly beautiful high art of Lascaux; and the upper range of the more conservative dates for the domestication of dogs.

The stunner, though, was that when they analyzed the wolf data alone, the gene appeared to be much younger: as young as 12,000 to 14,000 years, which bumps against the human colonization of the New World through the Bering Straight.

Anderson & Co.’s conclusion: New World wolves appear to have lost the gene for black color, possibly before the domestication event, and may well have regained it by back-crossing with dogs in astonishingly recent times.

Now, I hear some of you saying [actually, it’s Heather, more or less over my shoulder]: “Makes no sense. The gene for black color predates fur, for Pete’s sake: you can find it in fish, birds, and, well, us. How could it only be 50,000 years old?”

Interesting fact, though: that gene is for the Melanocortin 1 receptor, and causes black color through a slightly different tweak of the same biochemical pathway as the K locus. Different beast. [6]

So it appears that North American wolves had no black-furred individuals at all until people brought their homeys over the land bridge. But that’s not the really neat part.

Anderson et al. made another discovery, when they looked at the geographical distribution of the K locus: tundra wolves have the black version far less often then boreal forest wolves. It looks very much like the wolves who make their daily bread [7] in the dark of the pines are experiencing evolutionary selection in favor of black color.

So there you have it: domestication may not be a one-way street. Human activity can, sometimes, bring favorable genes back into wild populations. [8] It doesn’t change the devastation our footprint can bring in the slightest. But it does, perhaps, signal a glimmer of hope that our presence need not always be disaster personified.

And it feels good to know that our companions maybe gave something back.

[1] Responsibilities, time, and yes, some significant aches and pains, if you must know.
[2] Heather, me, and our two first SAR partners,
Lilly our steadfast anchor and Mel our superstar.
Debunked, as it turns out, as a treatment for snakebite, but to my mind still a credible tool for managing insect stings.
[4] Based on what’s being bred now, for the most part. Don’t get me started.
[5] Huge error bars here, as is often the case with these kinds of dates. But I’m using the mean because that’s where the probability maxes out.
[6] Dogs also have a second black-color gene, though wolves don’t share it.
[7] Well, sweetbreads anyway.
[8] Sure, we may be the threat that they need dark color to evade. What a cynical bunch you guys can be!


Luisa said...

Heather pretty much summed it up, though, in her unique, kill-a-man-at-20-paces-with-her-sarcasm way, when she said, “Very few of the wolves around here wear red backpacks.”

Only the ones that eat backpackers.

Also: Sean Bush [venom doc] is my homie. That is all.

Heather Houlahan said...

Algonquin wolves wear those holier-than-thou green backpacks -- but with the smug maple-leaf flag sewn on.

Wouldn't wanna be mistaken for one of those boorish Isle Royale wolves, eh?

My word today is milehalk

Ken Chiacchia said...

Hey, I think it was the season before we went to Algonquin that a wolf tried to drag a 12-year-old from the Pittsburgh area out of his sleeping bag. Very scary, but not unusual for the critters in Algonquin: their black bears, for instance, never seem to have gotten the memo that it's the grizzlies that eat people. Every 10 years or so, an Algonquin black bear will pass by a picnic basket and a pack full of Clif bars to kill and eat a person. Not exactly reassuring, but it makes a portage through a long, dark forest, with your dogs' fur on end as they prowl around you like curs waiting to be whipped, unique.