Tonto Creek rushes past my perch in the granite/gneiss heart of the canyon below Bear Flat.
Lobo lies on the grassy bank alongside me, having returned from his initial reconnaissance to resume his fitful study of the mystery of human motivation.
I am not sure he has accepted this whole fishing thing — despite the completely unpredictable yield of fish intestine treats. But then, perhaps his puzzled expression denotes a distant dose of coyote dung.
I love to take the twisty, five-mile drive down the two-wheel-drive-friendly dirt road that cuts off Highway 260 just before you get to Kohl’s Ranch. The road fetches up at the campground and chain of fishing holes at Bear Flat. Even such a short and benign stretch of dirt road filters out most of the flip-top-popping, flip-flop-flapping Lookiloos. A half-mile trek down toward where the creek enters the Hellsgate Wilderness takes care of the rest of the riff-raff.
Rumor has it that trout lurk beneath the sky-dappled surface of the pool, which gathers into a swirl above a cataract of stone just downstream. But you cannot as yet cite me as a source for the rumor. The stone is flood-smoothed and pink — rock forged miles beneath the surface a billion years ago, then thrust into the sunlight by a shrug of the continent and exposed to the sculpting of floodwaters just a geologic eyeblink ago.
Still, that blink no doubt exceeds the otherwise impressive time that Lobo’s ancestors and my ancestors have been working out their relationship.
No fish rise to molest my fly. I have lots of time for random speculations. Lobo sniffs the breeze, suddenly intent.
Read recently that some scientists have discovered a 33,000-year-old dog skull in a giant cave in Siberia. Thanks to extraordinary advances in reconstructing the genetic blueprint of DNA from bits and pieces, the researchers created a sample they could compare to both wolves and modern dogs. They also had a well-preserved jawbone, so they could compare the layout of the teeth to both wolves and dogs. I found the description of the research by folks from the University of Arizona and elsewhere on the Science Daily Web site, which referenced an article in the online journal PLoS ONE.
As it happens, scientists had previously unearthed the 36,000-year-old skull of another domestic dog in a cave in Belgium, from which they’d also reconstructed DNA.
Studies of diverse doggie DNA had already convinced experts that dogs diverged from wolves something like 100,000 years ago, presumably when they first took up with humans. The scientists based the estimate on the accumulation of little, random, meaningless mistakes in the coil of DNA that accumulate between genes at a more or less steady rate. These changes create a “molecular clock” that enables experts to estimate the time that has passed since any two species shared a common ancestor.
Now, here’s where it gets really strange. DNA comparisons among different humans show we’re all related to people who lived in Africa between 70,000 and 80,000 years ago. Dogs evidently hooked up with the ancestors of modern humans at just about the time we ambled out of Africa and occupied the whole planet. Some speculate we spread so far and fast because we were loping along behind great herds moving across Europe and Asia, our faithful hunting dogs trotting alongside.
Now, as it happens, another cave in Siberia yielded a 30,000-year-old finger bone and tooth from a previously undiscovered relative of modern humans, which scientists have dubbed the Denisovans, according to a study published in the journal Nature. DNA from a finger bone and a tooth from two different Denisovans turned up a genetic link with modern people living in New Guinea. This means their ancestors interbred with some Denisovans way back when. It also proves that the Denisovans lived scattered across the globe before modern humans showed up.
That mirrors the startling DNA reconstructions of the much better known Neanderthals — who lived scattered across Europe before modern humans arrived on their journey out of Africa. That analysis has revealed Neanderthal DNA in many European groups — indicating a little hanky panky back in the Ice Age.
So it looks like early human beings spread out of Africa about 400,000 years ago and gave rise to Denisovans, Neanderthals and other groups. Then 100,000 years ago, modern humans whose ancestors had stayed behind in Africa undertook another global migration — displacing distant relatives along the way.
As it happens, Lobo also has a pretty interesting family tree. Turns out the 33,000-year-old Siberian domestic dog and the 36,000-year-old Belgium domestic dog aren’t Lobo’s ancestors. They’re dogs — not wolves — but their lines both died out. So I’m thinking, maybe they died out because they got themselves dependent on the Neanderthals and Denisovans, who died out about the time we showed up.
Lobo’s ancestors, by contrast, bet on the winning biped — which would be us. Me, really.
Of course, in Lobo’s case — he’s got some pretty recent wolf thrown in for growls and giggles. Got back to his roots I guess. Domestic dogs have shortened snouts, wider jaws and more crowded teeth than wolves. Lobo, who adopted me on the streets of Tucson one fine day, falls somewhere in between.
I let my gaze drift from my floating fly to Lobo, sitting alertly on the bank, staring fixedly at a thicket of brush on the far side of the pond, very wolfish.
“Thanks for the company, fella,” I say conversationally. “I mean, you know, way back.”
He glances up at me. He understands more human than I’ve learned dog — no doubt about that. But I can see from the patient, condescension reflected in his golden-brown eyes that most of what I say strikes him as gibberish.
Then for the first time since I had deployed my fly rod, a hidden trout ruffles the surface — close by my fly.
I turn my rapt attention to the trout, which is why I do not see Lobo launch himself from the bank. He lands nearly on top of my fly and strikes out immediately for the far bank.
I wipe the splash of Tonto Creek from my polarized sunglasses and call after him. “Yeah, well, like I said, thanks for the help.”
Wonder if the Denisovans had such dog days.