Genesis of the Alien Cortex What’s the hidden tale behind the monkeys without tails – the eight “Great Apes” or Hominids? And why did one of them – us – become so numerous, so dominant, and even suit up and lope about on the Moon, while our seven cousins hang on the edge of the endangered species list by their fingernails and presumably hardly ever even gaze up at the stars? What set us on such different evolutionary paths? And how come the track we are on now seems to be headed for the destruction of our whole primate family and our home planet? Thanks mainly to our species, five of our evolutionary cousins are “Critically Endangered” (orangutans and gorillas) and two (common chimpanzees and bonobos) are merely classed as “Endangered”. The IUCN Red List of Threatened Species lists us in the conservation category of “Least Concern.” But an increasing number of forward-looking ecologists, anthologists, environmentalists and futurists are not as sanguine. Like bacteria in a fermenting vat before their last and fatal doubling, if you take a snapshot-in-time of our species then we are probably in our heyday. But we are also probably at, or nearing, “peak human”. In January 2020 the infamous Doomsday Clock was set to the closest it’s ever been to midnight – a mere 100 seconds short. Yet optimistic writers, like Steven Pinker, are at pains to point out that in “measure after measure, things have never been better.” For humans, that is. For most wild species outside the orbit of our domestic arrangements, things could hardly be worse. More insightful observers, like mathematician Sidney Smith, who take food, fresh water, waste, sources of energy, lack of biodiversity and human habitat, overpopulation and anthropogenic climate instability into account, come to the opposite conclusion. They think that, thanks to the very successes that Pinker celebrates, we will probably not survive the Holocene mass extinction event – a cataclysm of our own making. By cherry-picking a few positives, millenarian utopians like Pinker find it all too easy to brush off the dire big-picture dynamics of global overshoot, drawdown, collapse and unavoidable species extinction. Aside from such extreme points of view, how did our species get to such an extreme? What accident of evolution took us on such a wild excursion away from our closest primate relatives? The 20th Century saw a veritable cottage industry of theories to explain why humans were unique amongst primates (sotto voce … “superior” in the scala naturae or medieval Christian “Great Chain of Being”). Plausible theories were lined up like a coconut shy and knocked down one after another. One popular theory held that making and using tools set our species apart. Then researchers were shocked to discover that chimpanzees (Pan troglodytes verus) in southeastern Senegal routinely fashioned spears and used them to hunt bushbabies for meat. Jane Goodall discovered wild chimpanzees making specialized toolkits for foraging army ants, and soon various primates were found to use rocks as tools to crack nuts. Observers have even seen both bonobos and chimpanzees making "sponges" out of leaves and moss that they use for grooming. Darwin had a whole section on primates using tools in his book, Descent of Man (1871), but it seems to have been somewhat overlooked. He even mentioned baboons in Abyssinia having pitched battles, where one species used boulders as weapons and rolled them down on their rivals. So much for our uniqueness! If tools where not the key, others claimed that what set humans apart was “culture”. The theory claimed that humans were uniquely able to transmit behaviors socially, through cultural learning, whereas other primates could not. In the finest millenarian tradition, pedagoguery supposedly allowed humans to bank knowledge from generation to generation and therefore gradually accumulate the know-how to make the internal combustion engine, penicillin and rockets to reach the Moon. However, in the 1940s Japanese primatologists made the rather inconvenient discovery that macaques serendipitously discovered that sweet potatoes could be washed and salted in the sea and they transmitted that cultural invention/habit down the generations to this present day merely by active learning. So culture was definitely not unique to humans. By the 1990s the “cultural primatology” section of the library was overflowing with books about animal culture, and in particular chimpanzee culture. Another theory in the history of the human struggle for Apartheid from other primates held that language was the key differentiator. Famed linguist Noam Chomsky claimed that only humans had language. That idea bit the dust in the 1970s when cognitive scientists at Columbia University taught a chimp, scurrilously named Nim Chimpsky, to string sentences together using sign language. However, Herbert Terrace, the man who led the project, eventually became the most vocal critic of “animal language.” Although Nim learned about 125 signs, he was unable to learn syntax or the importance of word order. So Terrace concluded that no chimp could meaningfully master the art of language. “Animal language” is still controversial and hotly debated by the only species that claims linguistic ability exclusively for itself. It’s hard to untangle whether animals are just clever mimics, merely automatically responding to stimulus (like Clever Hans, a horse that looked like he could do basic arithmetic until it was revealed he was just responding to his human audience) or if they are genuinely communicating complex thoughts and feelings. Parrots are one of six groups of animals that develop some form of verbal language in order to function socially. The other six are various cetaceans, songbirds, bats, hummingbirds and primates. Some other animals also instinctively know how to vocalize and interpret the signals their species rely on to communicate and survive. For example, vervet monkeys use different alarm calls for different predators. The “snake” call makes them stand up and scan the ground, the “eagle” call makes them look up and scatter, and the “leopard” call sends them racing to the tops of the trees. This is all evidence of predator classification and semantic communication, so with such a great start, why haven’t monkeys evolved to hunt leopards to extinction with rifles the way we have? We are both close cousins and it wasn’t that long ago that we shared a common ancestor. So how did we turn the tables on our mutual ancestral enemy and tame it to become the domestic cat, while our other close cousins failed to? At the end of the 20th Century, many researchers hoped that the answer to our supposed uniqueness would be revealed in our genes. In 1990, the Human Genome Project (HGP) was launched with the aim of sequencing the entire human genome and identifying all specifically human genes. Scientists waited with great anticipation, optimistically expecting that a cornucopia of information was about to explode onto the scene. They eagerly anticipated finding the “gene for” everything one could possibly imagine. The “gene for” heart disease, sickle-cell disease, clinical depression, schizophrenia, maybe even the “gene for” suicide or cancer seemed on the cusp of being discovered, with the implication that there would be breakthroughs in the treatment of everything that ails our species. Finally it looked like we would get a complete insight into what really differentiates us from other primates. Excitement built as the book on what makes humans human looked like it was about to be opened (and closed) once and for all. In 2000, biologists literally started making a book to bet on the number of genes in the human genome. At the annual Cold Spring Harbor Genome Meeting, attendees took $1 bets on how many genes the human genome would turn out to have when sequencing was finally complete. The mean prediction was 61,170 genes, with the lowest guess at 27,462 and the highest at 153,478. In 2003, biologists were flabbergasted to discover that the human genome had only somewhere in the range of 20,000 to 25,000 genes! When you consider that the human brain alone has 86 billion highly organized neurons, that seems like a very compact instruction set for our entire blueprint. With so few genes, the whole notion of a “gene for” this or that had to be dropped (in all but the popular press, where it’s still in fashion, much to the chagrin of geneticists). Somewhere in that meager stock of physical functional units of human heredity was the crucial 4-letter coding difference between Noam Chomsky and Nim Chimpsky. By 2005 the chimp genome was finally sequenced and it turned out that our genes are about 98% similar. We are actually about close enough to successfully interbreed. Rumors of the “Humanzee” have circulated since the Tarzan movies came out in the 1920s, and in 2019, human-monkey chimeras were almost certainly created at the Salk Institute for Biological Studies in the US. But don’t expect research like that to ever get published! Bigotry and inter-primate Apartheid are still too firmly entrenched in our culture to allow things like that to get through a wall of massive academic censorship. The genetic difference between individual humans is about 0.1%, on average. The average difference between the chimpanzee (Pan troglodytes) and bonobo (Pan paniscus) genomes and ours is about 1.2%. Gorillas turned out to diverge from us by about 1.6%. The Asian great ape, the orangutan, diverges from us African apes by about 3.1%, and rhesus monkeys by about 7%. The age-old philosophical debate about what constituted the divide between humans and other apes was clarified in 2011 when landmark research pinned down what the essential genetic differences coded for (in as much as the concept of a “gene for” something is valid).
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