Posted: 29 Jun 2009 07:51 AM PDT

As the annual International Whaling Commission meeting stumbles to a close, unable to negotiate a compromise between whaling opponents and people who’ve killed more than 40,000 whales since 1985, scientists say these aquatic mammals are more than mere animals. They might even deserve to be considered people.

Not human people, but as occupying a similar range on the spectrum as the great apes, for whom the idea of personhood has moved from preposterous to possible. Chimpanzees, gorillas and bonobos possess self-awareness, feelings and high-level cognitive powers. According to a steadily gathering body of research, so do whales and dolphins.

In fact, their capacities could be even more ancient than our own, dating to an evolutionary explosion in brain size that took place millions of years before the last common ancestor of the great apes existed.

“If an alien came down anytime prior to about 1.5 million years ago to communicate with the ‘brainiest’ animals on Earth, they would have tripped over our own ancestors and headed straight for the oceans to converse with the dolphins,” said Lori Marino, an evolutionary neurobiologist at the Yerkes National Primate Research Center.

The idea of whale personhood makes all the more haunting the prospect that Earth’s cetaceans, many of whom were hunted to the brink of extinction in the late 19th and early 20th centuries, are still threatened.

At the annual International Whaling Commission being held this week in Portugal, officials failed to curb the continuing killing of some 1,000 whales every year, mostly by hunters from Japan, Norway and Iceland. Many scientists say populations are still too fragile to support commercial hunting or, in the case of Japan, “scientific research” that appears to kill an especially high number of pregnant females.

Mortality from hunting, however, may be the least of the whale’s worries. Industrial pollution has suffused their bodies with heavy metals and toxins. Noise pollution drowns out the vocalizations on which whales rely to find food and navigate. Overfishing punches holes in oceanic webs of life. Whales and dolphins are also accidentally caught in nets and struck by ships.

Such collisions appear to be pushing the North Atlantic right whale to oblivion, and the IWC says that ship strikes “should be reduced to zero as soon as possible.” But though the U.S. has set speed limits off its northeast coast, the World Shipping Council has fought such measures internationally. It’s also possible that Navy sonar tests, which may have caused mass beachings in the Bahamas, are to blame. The U.S. Supreme Court has struck down restrictions on the tests. And though President Obama has noble intentions on ocean policy, pollution and overfishing is a global problem.

nur02002In the midst of this, research has continued on whales and dolphins, which have long been difficult to study. Whales can’t be kept in captivity. Scientists require expensive ships and tools that, despite their sophistication, produce relatively low-resolution readings of whale life.

Most findings come from bottlenose dolphins, killer whales, sperm whales and humpback whales — the species that scientists have painstakingly studied for a few decades, and now continue their work with improved gene sequencing and song analysis tools. In these four species, scientists see considerable social complexity and individual distinction. They talk of whales and dolphins in terms of cultures and societies, and say cetaceans possess qualities of personhood. They say the same is likely true of other species, who simply haven’t been studied yet.

“It’s only due to our lack of knowledge that humans remain this exclusive species,” said Shane Gero, a Dalhousie University marine biologist. “We’re getting a lot of long-term studies in cetaceans, hitting multiple generations, and we’re finally able to get at these questions.” Though there’s still more evidence for primate than cetacean personhood, Gero said accumulating research “will start tipping the scales.”

Gero trained under Dalhousie University biologist Hal Whitehead, who started studying whales in 1977. Researchers from his lab and that of St. Andrews University biologist Luke Rendell, another former Whitehead student, have studied sperm whales around the world. They’re responsible for much of what’s known about the whales’ social behavior, which involves wide variations in group formation, hunting and child-rearing. Groups even appear to communicate in their own unique dialect.

“Based on what we know, I’d guess that cetacean culture is intermediate between humans and chimpanzees. Not in material culture, but in most other respects,” said Whitehead.

Culture is an especially important measure of personhood in whales, since it’s difficult to administer the sorts of tests that have found chimpanzees to be capable of basic math, altruism, laughter and complex communication, the latter of which can be neurologically imaged in real-time.

dolphinrecognitionBut if cetaceans can’t take these tests, they have met one critical laboratory benchmark of higher cognition: self-recognition. With Wildlife Conservation Society cognitive scientist Diana Reiss, Lori Marino showed that bottlenose dolphins can use mirrors to investigate marks hidden on their bodies. “When they look in the mirror, they’re saying, ‘That’s me,’” said Marino. “They have a sense of self through time.”

And in a much-celebrated first documented example of tool use in marine mammals, a family of dolphins in Australia uses sponges to hunt.

Cetaceans even surpass most primates in their use of sound. “We’ve known for some time now that the communication systems of these animals is more complex than we can imagine,” said Marino. “People are starting to use some interesting statistical methods to look at their vocal repertoires, and they’re finding structural complexity that suggests there may be something like grammar, syntax, even language.”

Fueling the evolution of cetacean communication is an ability, observed in dolphins, humpback whales and sperm whales, to pass songs and codas between generations and individuals.

“One of the ways in which dolphins are unusual among mammals is their ability to imitate sounds. Most apes are barely able to modify the sounds that they make vocally, based on what they hear,” said Peter Tyack, a biologist at the Woods Hole Oceanographic Institute. “To be able to learn sounds and incorporate them is really important for human communication.”

According to Tyack, the individually distinctive calls of dolphins may even be equivalent to names. “That’s an open research question,” he said.

In addition to cultural evidence, researchers who’ve studied cetacean brains — many of which are among the largest in the animal kingdom — have found highly developed analogues to human structures. Whale brains appear to have undergone massive growth about 30 million years ago, a process linked in primates to the development of complex cognition and culture.

“The parts of the brain that are involved with processing emotion and social relationships are enormously complex, and in many cetaceans even more highly elaborated than in the human brain,” said Marino. “If we assume that the limbic system is doing what it’s doing in all mammals, then something very high-level is going on.”

As for the nature of a whale’s inner life, it’s difficult to say but possible to speculate.

“My strong suspicion is that a lot of sperm whale life revolves around social issues,” said Whitehead. “They’re nomadic, live in permanent groups, and are dependent on each other for everything. Social structure is vital to them. The only constant thing in their world is their social group. I’d guess that a lot of their life is paying attention to social relationships.”

These relationships would be “interestingly different from ours, for a variety of reasons,” continued Whitehead. “There’s nowhere to hide, they can use sound to form an image of each other’s insides — whether you’re pregnant, hungry, sick. In a three-dimensional habitat, it’s probably much harder to say something is mine, or yours, whether it’s a piece of food or a potential mate.”

Tyler Schulz, another researcher in Whitehead’s lab, recently refined a method for linking sperm whale codas to the individual who composed them. That should help researchers get an even better appreciation of personal traits.

“He found that in one group, most of the animals had a similar repertoire of calls, but the mother of a baby had a different one,” said Whitehead. “As we analyze the data, we’ll be able to figure out whether that was the mother’s originally vocabulary, and she was a weirdo, or if maybe that was just baby talk. We all know women who change their vocabularies when they have babies.”

FROM PHANTOMS AND MONSTERS

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