Mind of the Raven: Investigations and Adventures With Wolf-Birds (44 page)

Consciousness would be particularly useful when there is a need to anticipate another’s moves, blow for blow. For example, a raven feeding with wolves on a carcass could potentially learn by trial and error how to avoid getting bitten and how to get meat. But how many wolf bites can a raven afford and still survive? If the raven could consciously anticipate the wolf’s moves and plot its own responses, it could avoid the first fatal mistake—the only one that really matters. Once consciousness has been selected to serve one purpose, it can be co-opted for use in other similar circumstances, in the same way that an insect’s wing is not only adapted for flight but can secondarily serve as camouflage, armor, sexual signaling, and shading.

The neural basis of consciousness is unknown, although opinions of what it may be range from presumptions of the existence of mysterious properties to the idea that it is little more than elaborating on memory. As previously indicated, I tend toward the latter view, because we already know that the vividness and depth of our consciousness is a function of the vividness and depth of our memories. Neurobiologists agree that consciousness requires the standard chain reactions of impulses traveling neuron to neuron in the brain, but probably in multiple neural circuits. The neural circuits traverse a labyrinthine jungle of inconceivable micro-anatomical complexity with almost unlimited possibility for input to affect the loops, and it is in this arrangement of neurons and their circuits that consciousness resides.

We’ll never find proof for the existence of consciousness by picking the animal apart, or by looking at its parts in isolation. That’s like trying to understand the caching behavior of ravens by grinding them up, examining ever smaller parts down to the molecules, and studying them through the laws of physics and chemistry. That’s backwards. To the biologists life is made of matter, but the nature of every living thing in the cosmos is time-bound. Every living thing is, like a book, more than ink and paper. It is a record of history spanning over two billion years. The more we dissect and look at the parts disconnected, the more we destroy what we are trying to find—the more we destroy what took millions of years to make. Mind, like life or liveness, is an emergent property that is a historical phenomenon, though also still wholly a physical one. It reveals itself far above and beyond its component parts, in this case, primarily the nerve cells with their infinite interconnections that cannot and will not ever be unraveled one and all. Consciousness is not
a
thing. It is a continuum without boundaries. We can most readily see its presence or absence in the extremes. In mussels, and in men. Is one of these extremes for birds found in ravens? Is it of sufficient magnitude for us to detect with our feeble detectors, our minds?

How can we envision a progression of steps leading from memory to consciousness? At first, the neural connections between different reverberating circuits could be loose and tenuous. Perhaps one pathway merely monitored when another was active. Then, with more
interconnections, it could monitor activity more precisely, ultimately to track the other circuit ever more accurately, sensing its cycle before that cycle is committed to muscular effort (i.e., behavior). By these analogies, a graceful action such as a swan dive, or a raven’s wing-dipping in flight, if not already hardwired, is first an idea. Repeated often enough, the thought becomes engraved in the nervous system. It becomes automatic, and no more decisions to guide its course are necessary beyond that of the “go” signal to execute the action. That is, it becomes unconscious, like most of our vital functions that run on “autopilot.”

The physical bases of emotions and feelings are potentially more of a theory problem than of mental representation, such as that underlying conscious insight and intelligence. Nevertheless, one might legitimately ask, why do organisms have subjective experience and emotions at all? I will add little here to that topic which I discussed (pp. 109-112) in my book
A Year in the Maine Woods
. I speculated there why it is unlikely that a lobster would feel boiling water, why a worm that writhes does not necessarily feel pain, and why a raven probably feels love and a dog not, and why a moth seeking a mate would likely do so without any conscious awareness. Pain has a function. It is not an “extra,” even though you can build a robot that recoils from a wall or a hot stove. Pain is a warning system that has evolved where choice is possible, that when coupled with insight or learning from experience, helps us avoid potential damage. If we feel the pain of a pinprick, then coupled with insight and/or learning, that sensation spares us the potential future damage of sitting on a spike. If we have a sensory feel of jumping off the back step and combine a memory and insight with it, then we won’t kill ourselves by jumping off the roof on a whim. We’d strenuously resist any such whim. An angle worm probably doesn’t have the need for a memory linking each of its behaviors with sensations, because it doesn’t need to make choices. We do, and so do ravens. Of course, it makes absolutely no difference what a raven’s private pleasurable sensation of eating raw skunk meat is, so long as it has one that links its memory with its reward system. The sensations may change dramatically, even in the same individuals. I recall one dramatic inci
dent. I had always loved the taste of cranberry juice after a hot jog. Later I was forced to drink gallons (by a cranberry juice producer who sponsored me on a championship race). I drank it for 100 km, even as I felt increasing unbearable agony. I tried it on my next race, and then it tasted to me like the most disgusting fluid I’d ever imbibed. I was unable even to drink water flavored with it (dispensed from the same bottle). My body had tagged cranberry juice as a pain-inducing substance. I had a choice, and exercised it. I stopped drinking. (I dropped out of the race.) My body avoided the pain it had previously experienced in association with that particular taste. Like the color of lobster pots spread around in Muskongus Bay that identify their owners, the
specific
sensations are arbitrary by themselves.

Sensations and emotions regulate behavior. We feel attraction, love, revulsion, jealousy, fear, happiness, determination, and anxiety, all governing responses largely connected with specific behavior relating to long-term survival and reproduction. They serve to motivate and guide behavior when there is no immediate reward or logic to guide us. When functioning properly, they inform us and keep us on the right track. Who, for example, has not felt happiness on being in the woods on a spring day, listening to the birds singing, the insects buzzing on the flowers, the green grass swaying in a breeze, seeing elk graze and fishes darting along the banks of a sandy stream? We are programmed to feel happy under these circumstances because we are experiencing the stimuli that through evolutionary history have represented the sort of productive environment we might seek for survival and reproduction. A raven or a rat’s neural centers would likely be wired to feel more internally stimulated by different scenarios, possibly a fetid dump or a beach littered with carcasses. Since ravens have long-term mates, I suspect they fall in love like we do, simply because some kind of internal reward is required to maintain a long-term pair bond.

Less specific emotions also help us stay on track for relatively short-term goals, again by rewarding us for intermediate steps. For example, we get no reward by turning to random numbers, say 10-8-3, on a combination lock on a chest full of money. If we
know
that the combination 10-8-3 will open the lock, allow us to reach the money, and that
the money will then buy us bread, we will turn those numbers as if almost “tasting the bread.” As Anthony Dickinson, a psychologist at Cambridge University, has pointed out, “Consciousness is necessary to confirm value.” Our values are emotional rewards that allow us to do otherwise proximally senseless things that have no immediate reward whatsoever. The same idea applies to a raven pulling a string. The bird gets no tangible reward from all the intermediate steps before it reaches the food. It needs an emotional satisfaction to do those nonrewarding steps. And it can only get an emotional satisfaction for the senseless act of pulling on a string, as such, unless that act satisfies a thought or mental scenario of getting what the string will provide.

Some believe that consciousness and the thinking derived from it are made possible only with linguistic ability. According to that very narrow view, humans are indeed the only conscious beings. But who of us translates everything we are aware of, thinks, or feels, into words? Who thinks only with sentences? We can all project mental images of ourselves or others throwing a ball, or envision how a bicycle operates, or know how to kill a bison with a spear. To transcribe such thoughts into words takes valuable time and effort. Of course, we can and do think with words, but that’s not because thinking requires words. It’s instead because we’re social animals who have evolved to use words to communicate, allowing us to transfer useful mental images into our helpers’ and associates’ minds. Admittedly language was not possible until we had achieved a critically high threshold of consciousness, which probably exceeded that of any other existing animal. After crossing that threshold, we needed even more consciousness to think using words, requiring still more consciousness, and that sped us down the road of cultural evolution. It was words, then, that enormously amplified our capacity to store and transfer knowledge, to build culture, to form alliances, to wage wars. The word became the weapon. I suspect the great gulf, or
dis
continuity, that exists between us and all other animals (as the one between those of us now manning a console on a moon orbiter versus those of us wielding spears) is ultimately less a matter of consciousness than of culture.

R
AVENS HAVE LIMITED CULTURES
and are closely and intimately tied to their external physical and biological environment, unlike us, who are culture-bound and only indirectly connected to the external environment. Throughout my studies, the goal has been to understand the birds’ life in their natural environment, which provides context to almost everything about them. Almost nothing about them makes sense unless seen from that perspective, in the same way that very little about us makes sense unless seen from the perspective of our culture. Nevertheless, to study details of their intimate lives is practically difficult or impossible in the complex, multidimensional wilds encompassing hundreds of square miles. At times, I detained groups of wild birds in aviaries for close observations. These aviaries were as large and as natural as I could make them. They did fulfill the birds’ needs—hand-reared and wild birds alike successfully built nests and reared young in them—but when it was time to release the birds, I was glad for them to resume their full, but much more risky, wild lives.

You will recall Goliath and Whitefeather, who were my particular friends. Goliath was hand-reared by me from a nestling, and his mate Whitefeather was a female he had met in a crowd of temporary captives. For reasons that are totally inexplicable to me, they immediately struck up a relationship. Whitefeather and Goliath built a nest in captivity, laid eggs, incubated and raised their own and another pair’s young. The couple stayed on my hill after I tore open one side of their aviary, and the surrounding area became their territory. After their first successful breeding attempt (inside the aviary) they returned on their own into the aviary the next year to build a partial nest, but they then aborted that year’s breeding attempt, possibly saving their energies for the next.

Having Goliath and Whitefeather as permanent residents on my Maine hill seemed like a dream come true. I could observe them closely on their terms, in their environment. What more could one want than to be surrounded by interesting friends who made no demands, who provided constant entertainment, and who were teachers. In the spring of 1997, the pair even provided me with new data I used for a paper on caching behavior in a prestigious international journal. I was high on these birds. Whenever I came walking up the hill to the clearing by the cabin after an absence of one to several weeks, I hollered “Golii-ath”—and I would soon hear him answer from the forest. Then he would circle over me, spiral down, and land on the dead birch tree by the picnic table. I’d pull a dead mouse or some other tidbits out of my pocket, and he’d drop down and swagger over in his slow, deliberate walk. Rachel tells me the moment she knew she was in love with me was one morning as she watched me sharing my oatmeal with Goliath in the yard. Whitefeather, who was still somewhat shy of me, would call from the nearby pine woods. She begged from Goliath, who shared the food that he got from me.

After mid-May in 1997 and through the summer and fall, I came up to a silent hill. No raven answered my call, and I felt a loss. Had something happened to them? I talked with the neighbor living in the shack at the bottom of the hill. Yes, he had seen them, he said. They had come several times and “made a racket” in the big pine tree next to his hut. But he couldn’t be sure of dates, and I couldn’t be sure if he
had seen my ravens, or some others, although he said he could by then recognize Goliath’s distinctive voice. The pair seemed to be gone. I still harbored a faint hope that they might occasionally be stopping by when I wasn’t around, and would perhaps resume their residence later on. I was absent from Raven Hill camp for most of the fall and early winter, and when I returned with thirteen students to teach a field ecology course in late December 1997 and early January 1998, I saw no sign of them. I gave up hope of ever seeing them again.

On the evening of January 10, just as we were about to leave and as I was walking out of the woods to the log cabin, I heard a raven excitedly making a loud commotion. Looking up, I saw to my great surprise a pair of ravens flying over with a third bird following, all heading directly to the aviary in back of the cabin. I stayed away from the aviary to avoid disturbing the trio. After an hour or so, I heard a female’s knocking call and continuous
rap-rap-rap
calls. The pair, or at least one of them, was back, and they were excited, possibly thinking about nesting. The next dawn, their calling resumed, and I felt confident that they were back to stay. In the first reds, blues, yellows, and turquoise of a glorious sunrise, all the trees shone like silver from their heavy loads of ice after the infamous five-day ice storm that had severely damaged the New England woods. Nevertheless, I felt happy.

As it was just barely getting light, I heard agitation calls from the aviary. At least one bird was extremely upset. I had not wanted to go near the aviary at that critical time for fear of discouraging their nesting, but these calls demanded attention. What in the world could be going on? To find out, I approached cautiously through the woods, at last seeing three birds fly up from or out of the aviary. One of them saw me, backpedaled in the air, and rapidly flew off. The second followed it. The third flew toward me and landed next to me.
Goliath!
He seemed nervous at first, perhaps because we hadn’t had contact since May, eight months earlier. He stayed near me, but seemed subdued and uninterested in me, even though I talked to him. I checked inside the aviary and found fresh raven tracks in the snow by the old nest. There could now no longer be any doubt. They were back! They were getting ready to nest.

I heard at least two ravens twice more at the aviary later in the day. In the evening, the calls came from near the edge of the pine grove just north of the cabin where Goliath and Whitefeather had often slept before. We had to leave that very day, and I had to be absent from Raven Hill camp for the rest of the late winter and early spring, due to teaching and other commitments in Vermont, and planned experiments with my six aviary birds there. Glenn Booma stayed at the cabin in mid-March and called me with exciting news; he had heard ravens in the aviary. He did not go near them for fear of disturbing them, but it was the proper time for ravens to start building new nests or refurbishing their old ones. I was confident that the pair’s old nest—the one that Goliath had built but that was never lined by Whitefeather—would now finally be lined with deer hair and ash and cedar bark, and would soon hold their eggs.

When I finally returned on April 29, I rushed into the aviary almost immediately to find an unpleasant surprise: The nest was just as it had been left a year ago. Hardly a twig had been altered. No lining had been put in, and it was now long past the time for the ravens to have eggs. I heard no ravens calling. Dejected, I walked to the pine grove in which they had roosted and which I had thinned out to favor the largest trees. If I were a raven, I thought, I’d build my nest
here
. I looked up. There, that dark mass ahead of me—a raven nest! As soon as I saw it, a raven flew to it with nest lining in its bill.

They were nesting now in the wild, and my spirits soared like never before. At the same time, I immediately contemplated the mystery of this extraordinary late nesting.
All
the other raven nests I had ever found at the end of April had young, many ready to fledge! This was the latest raven nesting attempt I had ever seen, out of nearly a hundred in this area. Might a disagreement among the pair have been the cause of the long delay? Perhaps Goliath, having grown up in the aviary, wanted to rebuild in the aviary, but Whitefeather, who grew up wild, did not agree. Last year, Goliath had built a nest-frame in the aviary, but she apparently had not agreed on the site, because she did not cooperate to finish buidling. She didn’t do her part, to line it with fur to receive the eggs. As a result, they had failed to breed. This year,
they had checked out the site again. There had probably again been a long disagreement, but she had won this time. They built on a pine tree in the tradition of other local ravens. Much valuable time had been lost. Apparently, there are advantages for ravens to have long-term mate relationships, especially if the birds come from different traditional backgrounds and with perhaps different expectations. In northern Germany, for example, most ravens nest on beech trees; in Maine, most nest in white pines; in Vermont, on cliffs.

On May 8, when I returned for a full week, I immediately went to the nest in the pine tree. Even from some seventy-five yards away, I could see Whitefeather’s dark head above the nest rim as she was incubating. She slipped off quietly on folded wings, diving down the valley toward Alder Stream. I saw only two birds near the nest at any time. Neither came near me, and neither showed alarm. Both were quiet.

I marveled at how quiet the birds were. But two days later, at 3:30
P.M.
, there was big excitement near the nest—lots of vocalizing. A heavy rain had just stopped, a cloud ceiling was lifting, and there was a slight wind. Were they excited about taking a flight? I rushed out of the cabin, sprinted down the path, and looked up. Sure enough, ravens were soaring in the breeze. But there were four of them together, and they were flying along amicably in a formation, as if on a mutual friendly romp in the sky. There were no chases, no aggressive calls as when intruders come or are being held off.

One pair split off and flew over the hill to the north, where less than two miles farther on I’d just seen four large fully feathered young perched on the branches around the Braun Road nest. Goliath and Whitefeather flew back toward their own nest. As fast as I could, I ran to the top of the ridge and climbed a tall spruce from which I watched the still vocal Goliath and Whitefeather flying closely together, circling, wheeling, diving, circling some more. It was great flying weather, and I could enjoy their play vicariously. I saw the pea green patches of freshly unfurled poplar trees in the valley below. Their light washes of brilliant green in the forest tapestry contrasted with the yellowish- and reddish-brown of red maples springing to life. Thick swaths of dark green red spruces and pines showed on the hills against a pale blue sky splashed
with drifting white cumulus. A thought struck me: Maybe they were excited because the young had just hatched. I almost tumbled out of my tree. I had to try to climb up to the nest, but large pines are not easy to ascend, especially without climbing irons, and I got exhausted in the attempt, finally giving up. By 7:30
P.M.
, the birds had long since returned to the nest, but I still heard sporadic bouts of
rap-rap-rap
calls. Whatever it was that had excited these ravens, it had made a big enough impression to last for at least four hours.

On the next day at 6:30
A.M.
, a red-tailed hawk flew by the cabin in the valley just below and toward the raven nest. The raven’s
kek-kek-kek
alarm calls erupted immediately, but lasted only the several seconds until the hawk had flown on by. Later, seven turkey vultures flew over a calf carcass I had left. Both ravens flew up, intercepted, and chased them away. They again made the
kek-kek-kek
calls, and again became totally quiet within seconds after the intruders had left.

I was still bothered by not knowing the reason for yesterday’s great excitement. It looked as if the cause was the other pair’s visit. But why did they come visiting? Why did Goliath and Whitefeather’s emotions continue to be high for four hours after they left? I decided I had to see inside that nest. Maybe their young had indeed hatched, and the other pair’s visit was incidental.

The tree was swaying in the wind, but it didn’t matter. I was determined. I clung tightly and inched my way up anyway, knocking off brittle dead branches as I climbed. After I reached the first solid branch that I could grab, it was easy. Within minutes, I was on live branches, directly under the great stick nest. Goliath and Whitefeather had left, silent. I swung around under the framework of broken-off poplar twigs as thick as my thumbs. I peered into the nest cup with great anticipation.

I have peered into many raven nests, but to be physically there always leaves me awed, especially after a risky, sweaty, hard climb. Four eggs! They were the most beautiful eggs I had ever seen. Their ground-color was green, like that of the then unfurling leaves of the birches, mixed with the blue of the clearest spring sky or that of the azure “little blue,” a butterfly then fluttering over the forest floor. They were blotched with dark olive green, like that of the spruce, and the gray
brown of pine bark. There were a few flecks of purple and a lot of gray and black. One, unlike the others, was most heavily blotched on the pointed rather than the round end of the egg. The four lay in a deep soft cup lined with tufts of white hair from a deer’s tail, shredded cedar and ash bark, chunks of pea green moss, and small tufts of black bear fur.