did he intend soul to connote some sort of immaterial or supernatural essence. He might just as easily have used the words song, water, or wave. For orcas, soul is a substance no different than the water that forms up on the surface of the sea from which the whales take their greater being. If the orcas could be said to have a goal that they seek to achieve, it would be the shaping of themselves into perfect waves that share the same water of life with all others. So vital is this imperative to bring forth the most beautiful manifestation of true nature that Arjuna speaks of the soul dozens of times. He liked to say that he was involved with the soul of humankind.
Of course, Orcas don’t mind repetition in their communications to each other. Or rather, the nature of the orcas’ ever-flowing language, as far as we understand it, makes boring repetitions nearly impossible, in much the same way it is impossible to step twice into the same surging stream. Each sound picture that an orca paints – even one so commonplace as that of a salmon – differs from all others in nuance, inflection, and the many colors of sound. The nearly infinite complexity of these sound pictures, like variations of themes in an open-ended cerebral symphony, engages an orca’s full attention at the same time that it discourages human examination. Sadly, human beings remain bound to essentially one-dimensional sequences of syllables spoken in time, and despite Arjuna’s assurances to the contrary, it is extremely unlikely that we will ever comprehend the three-dimensional language of the whales. We simply don’t have the mental machinery to do so.
More must be said about the human brain – its deficiencies and limitations – in comparison with the brains of orcas and other toothed whales. The mammalian brain has been built up by evolution in layers over millions of years. The foundational structure, the primordial paleocortex or reptile brain (called the rhinic), recalls the similar structures of the brains of fish, amphibians, and reptiles such as lizards and snakes. (Though it must be stressed that this does not imply that mammals evolved from reptiles, for instance, any more than humans did from chimpanzees. Both mammals and reptiles share a common ancestor in the Carboniferous period 300 million years ago.) The limbic lobe overlays this structure, as the supralimbic lobe does both. The outer lamination of brain matter is called the§ neocortex, whose growth over vast periods of time has enabled the leaps in intelligence of the mammals.
This ‘new brain’ – with its convolutions, fissures, and folds somewhat resembling those of a shelled walnut – is the pride of humanity. The brains of no other creature, it was thought for a long time, approach those of the human in differentiation, neural connectivity, sectional specialization, complexity, and power. Few of our kind have welcomed the discovery that the orcas’ (and other whales’) gyrification exceeds that of human beings. The surface area of a typical adult human’s neocortex measures about 2,275 cm2, while in dolphins, it is 3,745 cm2, and in orcas and sperm whales much greater. It is true that the orca neocortex is thinner than the human, but there is simply more of it folded up with greater complexity. To add insult to the injury of wounded human vanity is the fact that orca brains weigh in at three times the size of human brains – and the brains of sperm whales exceed in size our own by a factor of six.
For many decades, various scientists have thought to obscure this glaring and embarrassing reality. They have conjured up various ‘fudge factors’ in a desperate attempt to ensure than human beings will be number one in any ranking of species’ relative intelligence. Arjuna, in his account, with a simple thought experiment, demolishes the long-respected though ridiculous brain/body mass ratio as a measure of intelligence. (If this ratio proved true, the hummingbird would be the world’s smartest animal.) Realizing the limitations of the older metric, so-called scientists have invented a new one: the Encephalization Quotient (EQ), which measures the actual brain mass against the predicted brain mass for an animal of a given size. Of course, human beings with our large brains relative to our small bodies, again, come out on top. This, however, is not science; it is bosh. First, and most importantly, absent a method of universally measuring intelligence and correlating it with the EQ, it is just another voodoo statistic, sounding impressive but possessing no meaning. Second, while the EQ does an excellent job of fulfilling its purpose of distinguishing human intelligence from that of supposedly lesser beings, it fails in providing meaningful comparisons among other species. For example, the EQ of a capuchin monkey, about two, more than doubles that of supposedly much smarter gorillas and chimpanzees. Third, if some species are over-encephalized, mathematics necessitates that some species must be under-encephalized, therefore lacking the mental machinery to perform the basic cognitive functions necessary for survival. The usage of the EQ attempts to obscure the rather obvious fact that only a certain percentage of the brain is used to operate the gross functionings of the body, no matter how large (or small) that body might be. As it turns out, very little amounts of brain can account for rather amazing powers of muscle, bone, feather, and flesh. The peregrine falcon, the fastest bird in the sky, manages to perform its aerial acrobatics and compute its 250mph dives through the air to catch a darting dove by virtue of a brain the size of a peanut.
A better question, too little asked when considering what we think of as intelligence, would be to inquire how much of an animal’s brain can be devoted to the interconnectivity and association of ideas? In rats, this associative skill has been measured at approximately 10%. A cat tests out at 50% while a chimpanzee scores a 75%. Human beings, at 90%, thus need only 10% of our brains to operate our sensory and motive capabilities. What about the whales? The average associative skill measure estimated for cetaceans, at 96%, much exceeds our own, while orcas have available approximately 97.5% of their very large brains for a very wide range of cognitive functions.
More recently, Suzana Herculano-Houzel has argued in favor of another way to estimate intelligence, hitherto impossible to measure correctly. Citing the work of Williams and Herrup, she points out the reasonableness of assuming that the computational capacity of the brain should correlate with the absolute number of neurons in that brain, specifically in the neocortex, the supposed seat of animals’ higher cognitive abilities. How, though, to actually count the number of neurons in a brain?
In a brilliant piece of science, Herculano-Houzel succeeded in using detergent to dissolve the brains of various species to make a ‘brain soup’ in which neurons’ nuclei could be separated out and counted. The computations that resulted cleared up several mysteries. It turned out, for instance, that the elephant, with a brain more than three times as massive as that of the human being, does have more neurons; about 257 billion neurons compared to a human’s 86 billion. However, 98% of those neurons are to be found in the cerebellum; the elephant’s cerebrum contains a paltry 5.6 billion neurons compared to the 16 billion in the human cerebral cortex. That seems to explain our experience that human beings are a good deal smarter than the admittedly still-smart elephant. As Herculano-Houzel likes to say, ‘Not all brains are made the same.’ As she puts it, brains scale differently in different species and in different orders. The primate brain, and particularly the human brain, has evolved to pack more neurons more efficiently into a smaller volume, thus giving humans an advantage in intelligence over other species.
What, then, of the whales? Cetaceans share a rather close phylogenetic relationship with Artiodactyls such as pigs, deer, and giraffes. Based upon the scaling for those species, Herculano-Houzel predicted that the count of neurons in the much larger cerebral cortexes of several kinds of cetaceans would actually come out to a significantly lower number than that of humans. The largest cetacean cortex, that of the sperm whale, would contain fewer than 10 billion neurons, still much less than that of a human. It seemed that human beings’ ranking of number one would remain unchallenged.
There the matter stood until a whale hunt happened to deliver the brains of ten long-finned pilot whales into researchers’ hands. Using the techniques of optical dissector stereology, it was discovered that the neurons in the pilot whale neocortex numbered 37.2 billion – more than twice the human’s 16 billion. Heidi S. Mortensen, Bente Pakkenberg, and five others described the quantitative relationships in the delphinid neocortex in a paper published in Frontiers of Neuroanatomy. Their discovery should rank among the greatest in importance in the history of science. Instead, this very great breakthrough remains largely unknown. The cortical neurons of the orca have yet to be counted, but it would not be surprising if they topped out at over 75 billion.
As if all this weren’t enough