A female humpback was spotted in December 2005 east of the Farallon Islands, just off the coast of San Francisco. She was entangled in a web of crab-trap lines, hundreds of yards of nylon rope that had become wrapped around her mouth, torso and tail, the weight of the traps causing her to struggle to stay afloat. A rescue team arrived within a few hours and decided that the only way to save her was to dive in and cut her loose.
For an hour they cut at the lines and rope with curved knives, all the while trying to steer clear of a tail they knew could kill them with one swipe. When the whale was finally freed, the divers said, she swam around them for a time in what appeared to be joyous circles. She then came back and visited with each one of them, nudging them all gently, as if in thanks. The divers said it was the most beautiful experience they ever had. As for the diver who cut free the rope that was entangled in the whale’s mouth, her huge eye was following him the entire time, and he said that he will never be the same.
TO DATE, NO neurological studies of the gray-whale brain have been done. In 2006, however, researchers at Mount Sinai School of Medicine analyzed the brains of two other baleen species — humpback and finback whales — as well as those of a number of toothed whales like dolphins and killer and sperm whales. The study revealed brain structures surprisingly similar to our own. Some, in fact, contained large concentrations of spindle cells — often referred to as the cells that make us human because of their link to higher cognitive functions like self-awareness, a sense of compassion and linguistic expression — with the added kick that whales evolved these same highly specialized neurons as many as 15 million years before we humans did, a stunning instance of a phenomenon biologists refer to as parallel evolution.
“In spite of the relative scarcity of information on many cetacean species,” the Mount Sinai scientists concluded in a report in the November 2006 edition of the journal The Anatomical Record, “it is important to note in this context that sperm whales, killer whales and certainly humpback whales exhibit complex social patterns that include intricate communication skills, coalition formation, cooperation, cultural transmission and tool usage.” They added that it is therefore “likely that some of these abilities” are related to the comparable complexity in the brain structures of whales and hominids.
The sperm whale, for example, which has the largest brain on earth, weighing as much as 19 pounds, has been found to live in large, elaborately structured societal groups, or clans, that typically number in the tens of thousands and wander over many thousands of miles of ocean. The whales of a clan are not all related, but within each clan there are smaller, close-knit, matriarchal family units. Young whales are raised within an extended, multitiered network of doting female caregivers, including the mother, aunts and grandmothers, who help in the nurturing of babies and, researchers suspect, in teaching them patterns of movement, hunting techniques and communication skills. “It’s like they’re living in these massive, multicultural, undersea societies,” says Hal Whitehead, a marine biologist at Dalhousie University in Nova Scotia and the world’s foremost expert on the sperm whale. “It’s sort of strange. Really the closest analogy we have for it would be ourselves.”
Whitehead has even discovered distinct clan dialects using different codas, what he describes as a “Morse code-like pattern of clicks” that the whales make with their long head cavities and use to communicate with one another over many miles, reinforcing social bonds and declaring clan affiliation. Whitehead, who has been tracking and recording sperm whales around the globe since the early 1980s, has positively identified five distinct clan dialects and studied two extensively. “The regular clan,” he told me in a phone conversation from his lab in Nova Scotia, “makes three to eight equally spaced clicks. And then there are the Plus-One clans. They have two to eight clicks and then a pause and an added click at the end, kind of like the Canadian ‘eh.’ We’ve also noticed that these clans ply the water differently. Regular groups move in wiggly tracks closer to shore, while the Plus-Ones swim further from shore in straight lines.”
Whales display an incredible degree of coordination and cooperation in their efforts. Aaron Thode, an associate research scientist from the Scripps Institution, who was in Baja doing acoustical studies of grays, told me of another project he is involved in, using the latest research tools to gain insights into how whales perceive the world. He showed me an extraordinary video of sperm whales pilfering catch from fishermen’s lines in Alaska, 50-foot-long, massive-jawed behemoths delicately snatching a single black cod from a longline’s dangling hook, like an hors d’oeuvre from a cocktail toothpick. Fishermen are currently losing 5 to 10 percent of their yearly haul and fear the problem could become worse because whales who have mastered the technique are busily teaching it to others. The news seems to be rapidly spreading, as reports of similar fish-snatching are coming in from fishermen all over the world.
Humpback whales, meanwhile, have devised a prime example of what Fred Sharpe, executive director of the Alaska Whale Foundation, has described as “communal tool use.” Based on 20 years of observing humpbacks at sea and simulating their behaviors in the laboratory, Sharpe has been able to piece together the humpback’s rather ingenious fishing strategy. A group of humpbacks will get together and begin herding prey — herring, for example — toward the sea surface through the use of coordinated hunting calls. A designated leader of the group, meanwhile, will dive beneath the herded fish and emit from its blowhole an intense stream of rising bubbles, essentially forming a tube-shaped net to hold the fish in place. Waiting for the precise moment when the net has fully formed and captured the optimum number of fish, the group then rises as one, mouths agape, toward the surface.
Somehow the more we learn about whales, the more we’re coming to appreciate the sublimely discomfiting reality that a kind of parallel “us” has long been out there roaming the oceans' depths, succumbing to our assaults. Indeed, when that baby gray calf bobbed up out of the sea and held there that first morning, staring at me with his huge, slow-blinking eye, it felt to me as if he were taking one impossibly long and quizzical look in the mirror.
I asked Frohoff at one point if, given both the dark past of human-whale interactions in those lagoons and what we’ve now come to know about whale intelligence, there could possibly be some element of knowing forgiveness behind their actions. She took a deep breath and widened her eyes, making it clear that she wanted to be very careful about how she answered such a question.
“Those are the kinds of things that for the longest time a scientist wouldn’t dare consider,” she said. “But thank goodness we’ve gone through a kind of cognitive revolution when it comes to studying the intelligence and emotion of other species. In fact, I’d say now that it is my obligation as a scientist not to discount that possibility. We do have compelling evidence of the experience of grief in cetaceans; and of joy, anger, frustration and distress and self-awareness and tool use; and of protecting not just their young but also their companions from humans and other predators. So these are reasons why something like forgiveness is a possibility. And even if it’s not that exactly, I believe it’s something. That there’s something very potent occurring here from a behavioral and a biological perspective. I mean, I’d put my career on the line and challenge anybody to say that these whales are not actively soliciting and engaging in a form of communication with humans, both through eye contact and tactile interaction and perhaps acoustically in ways that we have not yet determined. I find the reality of it far more enthralling than all our past whale mythology.”
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