When was the last time you went through the old family photographs? Imagine doing it now, but in a very different way. This photo collection is titled "Time Machine." Everyone appears at your present age, and the first picture is of yourself. But next to yours is a picture of one of your parents, whose picture is in turn next to that parent's parent (your grandparent), then your great grandparent, and so on -
A few significant differences might be invisible, but present nonetheless. If you happen to have Tibetan background, you probably have a gene for high altitude-adapted blood that this ancestor did not have, and similarly if your background is Andean, because those genes spread more recently. Similarly if you have a Scandinavian or East African dairy farming background, you probably have a dairy digestion-adapted gene that this ancestor did not. Has your background has not yet been mentioned but you were still hoping for some evolutionary enhancement to distinguish you from your ancestors of 10,000 years ago? Not to worry much - there may be some and they probably will be discovered soon enough. But when all is said and done, the human of today is mostly indistinguishable from the human of 10 millenia ago.
back through time.
Four generations would take you back roughly 100 years. Forty - just a few pages of an old-fashioned photo album or a couple screens of thumbnails - would go back a thousand years. That's a ways back, but we're not finished. Four hundred generations would be about 10,000 years. That is a long time, yet the photos would still fit in an old-fashioned photo album, or alternatively perhaps 20 screens of thumbnails. However ten thousand years ago things were very different: no reading or writing (or school), no religion we would recognize today, and many other differences. The neolithic (agricultural) revolution was beginning, and no doubt you can fill in some of the other blanks. Yet, the most distant ancestor pictured, from some 10 thousand years ago, would look much the same as the most recent one - you (except of course for the clothes).
Four generations would take you back roughly 100 years. Forty - just a few pages of an old-fashioned photo album or a couple screens of thumbnails - would go back a thousand years. That's a ways back, but we're not finished. Four hundred generations would be about 10,000 years. That is a long time, yet the photos would still fit in an old-fashioned photo album, or alternatively perhaps 20 screens of thumbnails. However ten thousand years ago things were very different: no reading or writing (or school), no religion we would recognize today, and many other differences. The neolithic (agricultural) revolution was beginning, and no doubt you can fill in some of the other blanks. Yet, the most distant ancestor pictured, from some 10 thousand years ago, would look much the same as the most recent one - you (except of course for the clothes).
A few significant differences might be invisible, but present nonetheless. If you happen to have Tibetan background, you probably have a gene for high altitude-adapted blood that this ancestor did not have, and similarly if your background is Andean, because those genes spread more recently. Similarly if you have a Scandinavian or East African dairy farming background, you probably have a dairy digestion-adapted gene that this ancestor did not. Has your background has not yet been mentioned but you were still hoping for some evolutionary enhancement to distinguish you from your ancestors of 10,000 years ago? Not to worry much - there may be some and they probably will be discovered soon enough. But when all is said and done, the human of today is mostly indistinguishable from the human of 10 millenia ago.
Similarly humans 10,000 years from now will likely be mostly indistinguishable, physically, from those of today. Some interesting differences may occur, however. The most obvious differences will be cultural, with present-day nations, nationalities and ethnic distinctions, and even religions changed greatly, perhaps nearly beyond recognition. From a genetic standpoint, the most dramatic possibity is that organized selective breeding will occur. Dogs have been bred for about 15,000 years, and it is amazing how much they can differ from each other as well as from their wolf forebears after such a short time. In humans there is little precedent for this process. But there is also little doubt that deliberate selective breeding could potentially produce, in just few generations, super-athletes, super-geniuses, super-wine tasters and so on.
Perhaps slightly less dramatically, a selective sweep could modify the human genome in short order. Consider long-term nonprogressors, the tiny percentage of people who have the HIV virus but do not become ill from it and thus do not need medicine. They do not "progress" to obvious illness. Unless a very cheap and effective cure for HIV is found, over the next 10,000 years the genes that protect these long-term nonprogressors are likely to become the rule instead of the exception.
Another apparently on-going selective sweep relates to alcohol. I recently witnessed a tall man exiting a liquor store on a Friday afternoon with a hefty payload - and the expression and demeanor of naked intent to get home fast and begin another weekend to remember (or forget). The past 10,000 years appear to have witnessed an ongoing selective sweep of the genetic ability to comparatively rapidly metabolize alcohol, clearing it from the body with the enzyme alcohol dehydrogenase. Populations not exposed to much alcohol until more modern times, like native Americans, tend to have higher rates of alcohol abuse. The havoc that alcohol causes abusers and their families is so great that it is nearly inconceivable that licensed sellers can sell it to abusers. Licenses should be required of purchasers. Each license could be a plastic card with an embedded chip that records purchases and permits them only at non-abuse rates.
Currently, the world is so awash in substance abuse that there may be significant genetic selection for resistance to addictive substances. Intriguingly, while some genes apply only to specific intoxicants, like the alcohol dehydrogenase gene, others may affect susceptibility to addiction in general. Why is this intriguing? Because potential for addiction is built into the brain, more in some people than in others. Likely that potential is there for a reason, with the addiction issue present only as an accidental side effect. It might be a good reason; we just don't know. As addiction is bred out of the human genome, brains, thus minds, thus society will change. But in what ways? The reader might enjoy speculating, because that is about all one can do as the facts are not yet known.
Go back a hundred thousand years, 4,000 generations, and things are different. Now you'd need about 10 photo albums or a couple hundred screens of thumbnails to hold a snapshot of just one person in each generation. What would your ancestor from then look like? For one thing, he or perhaps more likely she might be a Neanderthal. Biologically, humans today belong to one race. Back then, however, there were two. One was us, and the other was the Neanderthals. (See http://en.wikipedia.org/wiki/
between these two races of humans occurred, leading to a small but significant fraction of the average non-African person's genome being Neanderthal. Physical features of Neanderthals often considered "distinguishing" can in fact be found in some people. For example some people have an occipital bun - a bump or protrusion on the back of the head. Other people might have particularly heavy brow ridges, or thick, bowed thigh bones, or a barrel-shaped rib cage, and so on. The photo from 100,000 years ago in your collection might indeed be a Neanderthal, however, more likely it would not be. What would it look like, then? It wouldn't be a Flores Man (Homo floresiensis), the 3-4 foot tall hobbit-like species whose bones have been found on Flores Island, Indonesia. Apparently more closely related to humans than any other species, these short, hobbit-like hominids (if one hesitates to call them people, "animal" induces hesitation as well) survived at least until 12,000 years ago and just maybe almost into modernity, possibly giving rise to the Floresian Ebu Gogo ("grandmother who eats everything") legend. Perhaps Flores Man still exists, living unnoticed in jungles of the region.
If this picture from a hundred thousand years ago was not a Neanderthal, then what was it? Except for the Neanderthal race, humans had not yet left Africa. Hence doubtless they had not yet developed the light skin color adaptation that enables better vitamin D production in the diminished sunlight intensity of higher latitudes (at the price of increased susceptibility to sunburn and skin cancer). For the same reason, today's modest regional variations in facial features had not yet developed, nor had any other present-day regional genetically based variations, from visible and known (green eyes, etc.), to unknown and waiting to be discovered in the future.
100,000 years ago we were different, but hardly unrecognizably so. Thus, it is likely that 100,000 years from now we will also look different - yet still clearly human. At 4,000 generations, that many years is enough for even very slight selective pressures to cause significant evolutionary changes to the human species. Today's regional variations in appearance (facial features, stature, skind color), which did not exist 100,000 years ago, will be long since lost in the mists of history. If we can identify existing evolutionary pressures and extrapolate, thus envisioning their magnified effects, that might help characterize humanity as it moves forward toward 100,000 year from now. If the brain is our essence, that essence will change. But how? Here is just one example (science should identify as many others as possible).
Do you think a gene for high ability to distinguish between fantasy and reality will tend to propagate to the next generation more successfully than poor such ability? I am not so sure, but suppose for a moment it will. Now consider a part of the brain that correlates with and likely confers just such an ability: the paracingulate sulcus (PCS). Some people have two well-developed PCSs (one in the left hemisphere and one in the right). Some have just one. Others none. PCSs can be well-developed, missing, or anything in between. It might not be long before an eye witness in a high-stakes criminal court case will have the size and number of her paracingulate sulci splashed across news screens world wide. Dating services will soon have decide: are people with similar PCSs more compatible, or is this a case where opposites attract? It is suggested that of two individuals with the same degree of schizophrenia-induced hallucinations, the one with better PCSs will likely handle it better and be more able to function. (It is unknown if Nobel prize-winning economist and schizophrenia sufferer John Nash has good PCSs or not. Einstein's brain, however, is in storage and could be checked.) Chimpanzees do not have paracingulate sulci. If good paracingulate sulci, on balance, benefit reproduction, in 100,000 years most everyone will have good ones. If the opposite - no one will!
A million years. Despite the foregoing, a hundred thousand years ago people looked like - and were - people. But go back a million years and things were different. For one thing, the modern lack of other species very similar to us (i.e. also in the genus Homo) did not hold. There were others, very similar in many ways, yet different as well. Not only Homo floresiensis (the "hobbits"), but also Homo antecessor and Homo heidelbergensis. Antecessor lived up to about 800,000 years ago and was roughly the height of modern humans, though of more robust build. Bones showing damage from stone tools suggest that antecessor both practiced cannabalism, and used tools, sometimes at the same time.
Their brain size was about 20% below ours, which still counts as large and, apparently, intelligent. With a low forehead and not much chin, they are only known to have lived in Europe. Homo heidelbergensis lived more recently than antecessor and may in fact be evolved from antecessor, just as we will evolve into something different if we survive long enough. They lived more recently than antecessor and may in fact be evolved from antecessor, just as we will evolve into something different if we survive long enough. First discovered in the form of a jaw found near Heidelberg in 1907, Heidelbergensis stood tall, about 6 feet in Europe and often exceeding 7 in South Africa, and was muscular and strong. The European population of heidelbergensis is likely to have evolved into the Neanderthals. The African population may have evolved into modern humans, which would make heidelbergensis our common ancestor. Compared to heidelbergensis, however, we have higher foreheads and flatter faces, and are smaller boned. (Technically speaking, heidelbergensis was "robust" while we are "gracile.") In this we are not unlike a heidelbergensis child, illustrating our neoteny - the slowing of development, tending to lead to the retention of childhood characteristics into adulthood. Neoteny is considered a broad characteristic of modern humans compared to our ancestors. It helps explain our relatively long trunks, short limbs, small brow ridges, small noses, high foreheads, and flat faces. This trend may continue into the future. Neoteny is also a broad characteristic of dogs, which are neotenized wolves.
To further illustrate the amount of evolutionary change that can occur in a million years, consider the modern primates most closely related to humans, chimpanzees (Pan Troglodyte) and bonobos (Pan paniscus). These species split from their own common ancestor roughly a million years ago. The bonobo is smaller than the chimpanzee, but behavioral differences are dramatic. Far less aggressive than the chimp, the bonobo is known for its unique sexual life. Bonobo sex, both hetero- and homo-, has an important place in the everyday function of bonobo society, for example in smoothing over conflicts to avoid fighting. This seems to be absent in the larger, more aggressive and dangerous chimpanzee. Additionally, bonobo society is mostly matriarchal (female dominated) while chimpanzees are highly patriarchal (male dominated), with a dominance heirarchy in a troop placing essentially all adult females below all adult males. Given such huge behavioral differences, it is likely that Homo heidelbergensis temperament, behavior, and society differed considerably from our own (and from traditional human tribal societies, which also tend to differ greatly from each other). Behavioral differences likely exceeded the not inconsiderable differences in appearance and physique. We will never know this for sure, of course, but we can make some guesses about them. The general developmental principle that humans are neotenized relative to their predecessors most likely influences our emotional development as well, resulting in human adults having some temperamental characteristics more typical of heidelbergensis youths than heidelbergensis adults. If one has trouble believing that neotenized physical characteristics have much to recommend themselves for physically dealing with the world - running around, finding food - as I do, then one must suspect that it is the neural and temperamental characteristics provided by neoteny that drove the neotenization of our species, with our also-neotenized physical characteristics being an accidental side effect. So what might those neotenous brain and mind-related traits be?
One trait relates to the fact that retaining juvenile characteristics tends to delay adulthood. This means a longer childhood, which today's developed nations use for extended schooling. A lengthened childhood period helps here, as you can't teach an old dog new tricks (so the saying goes). In fact, human childhood is so long that most other animals die of old age in the time humans take just to grow up. By extending youth, humans likely have a longer period of high neural plasticity, supporting improved ability to learn over a longer period of time. Still, like old dogs, old humans in some ways learn less quickly. In the future, if neoteny proceeds further, that may change.
Dogs can serve as more than a source of sayings. They also provide a great example of neoteny themselves. Dogs are a neotenized form of the gray wolf, domesticated at least 15,000 years ago. Since that time, they have held on to their position as "man's best friend" in large part because of neotenized aspects of their temperaments. Why? Remember that a standard gray wolf is *not* man's best friend. A gray wolves would *eat* a man (woman, and especially child) if it figured it could get away with it. Gray wolves (fighting weight may exceed 120 pounds) are definitely not good with small kids, like so many dogs are. Wolf puppies, however, are cute, fluffy, playful and fun, like many adult dogs. (In fact, so are the fiercest lion and grizzly bear cubs.) Thus neotenized mammal adults like us may be expected to be comparatively friendly, sociable and playful. And cute: we appear genetically predispositioned to find juvenile characteristics like short arms, roundish, flattish faces with short or no muzzle, and small noses endearing. Can you think of any politicians that one might suspect benefit in popularity from possessing neotenously cherubic or "cute" physical features? Many other animals are analogously programmed. This helps the young to benefit from, rather than be forced to compete with, the superior experience, skill and strength of parents and other adults.
The amounts and types of evolutionary differences between us and H. heidelbergensis suggest the amount and types of evolutionary change we may undergo in our next several hundred thousand years. Thus our brains may enlarge, perhaps by around 20%. Will that make every man an Einstein, every woman a Curie? Perhaps (and perhaps much more than that). Einstein's brain was on the small side, but surely an extra 20% would be good for something. Considering bodies, with heidelbergensis's robust physique and our gracile one, if this trend continues basketball has good long-term future prospects, while sumo wrestling may eventually face some challenges. No need to panic though - at a time scale of hundreds of thousands of years there is plenty of time for sports franchises to adapt to changing times. Moving to neoteny, a continuation of the trend toward increased neoteny suggests a distant future of shorter limbs and longer trunks, baby-faced adults, and more playful, friendly cultures. Hopefully, increased neoteny, by in a sense lengthening youth, will result in longer natural life spans, since getting old is not exactly a sign of youth.
Chimpanzees and bonobos, our closest living relatives, split from their most recent common ancestor about a million years ago and thus their differences form an interesting animal analogy to the amount of change we might expect in ourselves at that time scale. They look quite different and act even more differently, with chimp society patriarchal and bonobos matriarchal. While chimps are promiscuous in a sense any human can understand, bonobos raise to a whole new level the integration of sex into multiple facets of daily life. Bonobo philosophy seems to emphasize the "make love not war" concept far more than humans. There may possibly be human swingers and adult industry careerists who could empathize with bonobo society to a degree, but to most of us it's pretty alien. In a million years our descendants may be similarly alien to present day human understanding, but the only way to tell for sure is to wait and see. Since no one except a few die-hard singularitarians expect to be able to wait that long, the curious will simply need to use their imaginations, so imagine away if you like and bon voyage.
Ten million years ago, things were very different. It is thought that our ancestors of that time, roughly 400,000 generations ago, were hominids (Latin: Hominidae) who had not yet branched out into their current descendant - orangutans, gorillas, bonobos, chimpanzees - and us. The hominid family and our genus, Homo, are well-known, landmark taxa in our evolutionary tree. However there are also superfamily, subfamily and other auxiliary taxa that are instructive (or maybe just confusing!) to mention.
The hominid family forms a branch of the hominoid superfamily, which also includes gibbons. The hominids branch in turn into orangutans and the hominine subfamily (last syllabus pronounced like the word "nines"). The hominines branch into gorillas and the hominin (no "e") tribe, which in turn branches into chimpanzees and bonobos, on the one hand, and the hominan (with an "a") subtribe on the other, of which we are the only surviving example. The hominans contain the genus Homo, or humans. This terminological mess of hominthises and hominthats may seem ridiculous! And maybe it is. However, one way to help remember the ordering is to keep in mind that the homin- terms are - almost - in alphabetical order from smallest to largest grouping: hominan, hominin, hominine, hominid, hominoid, with 1 exception. Hominid is out of order but at least next to the other d-containing name, hominoid.
Some milestones of prehistory. About 75 million years ago, primates split off from the rest of the evolutionary tree of life, or the Linnaean taxonomy, after Carl Linnaeus (1707-1778), the Swedish scientist who created this branching map of evolutionary relationships that bears his name and is still with us today. 75 million years is a fairly long time ago, even for biological evolution; our roots go deep! Apes diverged from the monkeys about 32 million years ago. Apes were the first "hom-," the hominoids. The great apes, technically the hominids, came along around 19 million years ago. They include orangutans, gorillas, chimpanzees, bonobos, and humans. Moving into the upper reaches of the 1-10 million year ago time scale, a likely common ancestor race of all living hominines, from gorillas to us, but not orangutans since they had already branched off, was the Nakalipithecus. A partial fossil was found near Nakali, Kenya. This hominine is just under 10 million years old.
Gorillas then split off around 7 million years ago. Chimps and bonobos split from our common ancestral species roughly 5 or 6 million years ago. That species enjoyed considerable success in its day, spawning almost 2 dozen separate identifiable human-like hominins. Most are somewhat obscure, though our earlier-mentioned friends neanderthalensis, habilis and ergaster are among them. Although only 1 strain survives today, us, this remarkable species has pretty much achieved world domination. The jury is still out on its fitness to rule but the question will certainly be resolved sooner or later. Perhaps you are reluctant to call such extinct species as Homo habilis (Latin for "handy man") and Homo ergaster ("working man") human. If so, recall well-known hominid Groucho Marx, who famously opined, " I don't want to belong to any club that will accept me as a member."
The dramatic changes over the past 10 million years will most likely be mirrored in the next 10 million. But how? There are many ways, but let us focus on brain size and intelligence.
Humans may be characterized as big headed, and we're proud of that. Our brains are big, bigger than all but a few very large animals, elephants and whales in particular. But we are way ahead of even those animals on other crucial brain measurements. Since the brain mass of a species tends to increase with species body size, but not as fast, a measure called encephalization quotient is often used to express the deviation of brain size from what would be expected for a given body size if the organism had an average encephalization quotient of 1.0. On that metric, human brains are over 7x bigger than expected for an organism of our size. No other animal is that high. One survey puts elphants and whales at 1.3x and 1.8x respectively. Bottlenose dophins get to a little over 5x, and their brains are in fact close in size to ours, possibly making them geniuses of the animal kingdom. White-fronted capuchin monkeys get to almost 5x although absolute brain size is a lot less than for humans because their body size is so much smaller. By contrast, cats are 1x, while dogs are 1.2x. The lowly and somewhat homely opossum, at a mere 0.2x, might thus be characterized as better endowed with beauty than brains.
Even ignoring body size entirely, we are still way ahead on the number of neurons in our brains. Those big animals with brains bigger than ours actually have fewer neurons, the information processing units of the brain. By analogy, ordinary computers are getting more powerful year by year not because they are getting bigger but bcause their processors are being made with more information processing units (which for computers are not neurons but transistors). These transistors are actually getting smaller over time. Thus computers, as they get more powerful, are actually getting smaller, not bigger.
A dramatic process of brain enlargement in our past began approximately two million years ago. Our brains have literally tripled in size since that time. Presumably, that is why some primates like bananas, while some of us like books in addition to bananas. What if this process continued? Will our brains triple again over the next couple million years, giving us descendants who chuckle condescendingly at our admiration for mere books as we might chuckle over a monkey's admiration for mere bananas? Would such brainy descendants find the solutions to our most vexing problems of war and peace, poverty and excess, illness and health, love and hate obvious and easily taught in elementary school? Perhaps they will, but there are serious limits such rapid brain growth. These limits appear to forbid brain size (measured as number of neurons) from increasing at a rapid clip forever. Specifically, another tripling would, it appears, rqeuire major changes in brain structure surpassing the structural differences between human brains and those of other apes - in short, a major evolutionary leap requiring significantly more than a measly few million years. On the other hand, doubling brain size can be done more easily (and presumably quickly) because no major architectural changes would be necessary. Thus, our brains can fairly easily double, but tripling would be more problematic.
Here is a mathematical explanation of why. First, the brain is composed of many chunks which must communicate with each other. In contrast, the old syncytium theory that the brain is essentially a big blob of weakly organized tissue, sort of like a big ball of cotton, had been largely disproved by Spanish neuroscientist Ramon y Cajal by 1900, a feat for which he won the Nobel prize in 1906. The bigger the brain, the more chunks there are that need to communicate. The more communicating chunks, the more neurons need to be devoted to communication (thus acting like the telephone wires and internet cables of the brain). Let's see why this is a problem.
Suppose 3 chunks, 3 people, 3 computers, 3 offices, or 3 of any kind of communicating entity all need to communicate with each other. How many communications paths are needed? Three: one between A and B, one between B and C, and one between A and C. Suppose we add a 4th communicator, D, that needs to communicate with all the others. How many more, new paths are needed for all to communicate? Four minus one, or three: between D & A, D & B, and D & C. We added one more communicating chunk and needed to double the communication paths. The problem just gets worse the more chunks we add: the thousandth chunk requires adding 999 new communication paths, running between the new chunk and each of the previous 999. The fourth chunk needed 3 more paths but the thousandth needed 999! Thus adding one new chunk to a large brain that already has lots of chunks requires lots of extra neural tissue to be added for communication purposes. In practice, this is the white matter of the human brain cortex which, because of this problem, forms a disproportionate fraction of the human brain compared to other primates. It gets progressively more biologicallly expensive to incrementally increase brain capacity and humans are in the zone where this expense starts to become prohibitive of dramatic increases.
Of course, only doubling our brains is nothing to sniff at and could lead to impressively brilliant descendants, even if much more than doubling proves unachievable. We can only hope that such high-flying beings can still smell the flowers and, indeed, enjoy an occasional banana.
Recommendations
The future of the human race will be, to a significant extent, written in our genes. Much about us at present is written there now. But we know too little about what those genes say, what variations in them do, and what new and beneficial variations are possible. Such information will enable, for example, advanced medical interventions, the beginnings of which are occasionally in the news now. To add to knowledge of our genes it will be helpful to develop animals whose genes are replaced by homologous human genes, so these genes can be more effectively studied. Humanized mice are now available and increasingly used in cancer research and other laboratories. Still more knowledge would become available by humanizing other animals as well. Eventually, unusually intelligent dogs could come to replace ordinary pooches as "man's best friend." But studying our genes is also done without humanized animals.
By comparing our genome to those of chimpanzees and other primates we can deduce a great deal about ourselves from those genes we share and those that differ in small or large ways. We can deduce not only when we split from them, but how physical characteristics vary and how fast it can take for changes to occur. Thus we can tell that several million years hence our descendants will look quite different from how we look, perhaps as much as we look different from creatures that split from our line several million years ago, like chimpanzees. But those descendants probably won't look as different from us as bats, cats, or starfish. Many important conclusions remain to be discovered by advanced scientific techniques for comparing our genome with those of related animals. Yet many primates are decreasing in population and are now, or may become, at risk of extinction. Every such extinction will close off access to genomes and associated phenotypes (traits of the organisms) that have much to tell us about our past and, maybe, our possible future. Understanding how we got where we are now can shed considerable light on where we could go, what our genetic potentials are, and how long it might take to reach them.
Thus, preservation of primate species is in our interest and strongly recommended. The diversity of gorilla populations is one example of concern, as numbers of gorillas in distinct population locations are decreasing precipitously. At stake is not just understanding of our distant past, but of our possible futures as well.
Human evolution has produced great change, and great strides, over the past 10 million years. But wouldn't it be nice if changes we might desire - much better brains, markedly more athletic bodies, adaptations helpful in colonizing other planets and moons, resistance to diseases from malaria to flu to heart disease, much longer lifetimes, ability to reproduce without need of assistance from the opposite sex (most plausible for women), inborn dislike of the taste of junk food (or alternatively, ability to nutritionally thrive on junk food since it is sooooo tasty), three hands since everyone knows that sometimes two are just not enough, and so on. And wouldn't it be even nicer to get such things without those annoying multi-million year lead times. Certainly in 10 million years "we" will look very different regardless, but changes can potentially happen vastly faster, and in desired directions, if change is managed and controlled appropriately. Far from the eugenics movement of the decades surrounding the year 1900, which was so scientifically naive and blatantly racist as to make one doubt the mental fitness of its proponents, a new movement would be aimed at encouraging genetically updated people to be created and to exist, instead of the discredited concept of discouraging out groups from reproducing.
How might this new "benegenics" approach work? Benegenics would involve, first, screening people for new and rare mutations. It is those genes that will eventually rule the future. It is also those genes with the greatest potential to help change the human condition - for the better, but maybe for the worse if we are not both careful and wise. While by definition a very small proportion of people have genes that are both rare and valuable, the total number of such persons is larger now than throughout all of human history and prehistory. The simple reason is that there are more people in existence now than ever before. Once identified, such people may often be willing to participate as research subjects to expand human knowledge about our genetic potentials, particularly if paid. As for the rest of us, we are each unique in our combination of genes, but that uniqueness is not passed on to our descendants. Our children contain their own unique genetic mix, but that mix is composed of the same genes found in countless others. Your genetic recipe is unique but the gene ingredients are standard. The ingredients get passed on down the generations but the recipe gets changed each time such that it is rarely more than barely recognizable across even a couple of generations.
Even genetic differences between ethnic and racial groups are minor contributors to the human genetic range, because genetic diversity within ethnic and racial groups is known to dwarf average differences across groups. The few genes that cause visible distinctions between some groups may seem noticeable but tend to be only skin deep (literally), and not determine deeper aspects of the human condition. Consequently the self-serving pipe dream of the old eugenicists, that suppressing reproduction of people unlike themselves would improve the human race, is naive. It is also socially destructive - contradicting the movement's own stated goal of a better society. The contribution one may hope to make with one's children is not genetic but social and cultural, because constructive people benefit the world and every little bit helps.
References
"If you happen to have Tibetan background...": J. K. Pritchard, How we are evolving, Scientific American, Oct. 2010.
"On the other hand if you have a Scandinavian or East African dairy farming background...": Pritchard, How we are evolving.
"But there is also little doubt that deliberate selective breeding could potentially produce, in just few generations, super-athletes, super-geniuses, super-wine tasters and so on." R. Dawkins, The Greatest Show on Earth: the Evidence for Evolution, Free Press, 2009.
"Apparently more closely related to humans than any other species, these small hominids...survived until at least as recently as 12,000 years ago...": M. J. Morwood, P. Brown, Jatmiko, T. Sutikna, E. W. Saptomo, K. E. Westaway, R. A. Due, R. G. Roberts, T. Maeda, S. Wasisto, and T. Djubiantono, Further evidence for small-bodied hominins from the Late Pleistocene of Flores, Indonesia, Nature, Oct. 13, 2005, vol. 437, no. 7061, pp. 1012-1017.
Http://www.ncbi.nlm.nih.gov/
"Now consider a part of the brain that confers just such an ability: the paracingulate sulcus (PCS)." M. Buda, A. Fornito, Z. M. Bergstrom, and J. S. Simons, A specific brain structural basis for individual differences in reality monitoring, The Journal of Neuroscience, Oct. 5, 2011, vol. 31, no. 40, pp. 14308-13.
"Chimpanzees do not have paracingulate sulci." M. De Haan and M. H. Johnson, The Cognitive Neuroscience of Development, Psychology Press, 2003.
"Bones showing damage from stone tools suggest that antecessor practiced cannabalism, aided by tools." Y. Fernández-Jalvo, J. Carlos Díez, I. Cáceres and J. Rosell, Human cannibalism in the Early Pleistocene of Europe (Gran Dolina, Sierra de Atapuerca, Burgos, Spain), Journal of Human Evolution, Sept.-Oct. 1999, vol. 37, no. 3-4, pp. 591-622. http://www.sciencedirect.com/
"The great apes, of which we are kin, came along around 19 million years ago." M. E. Steiper and N. M. Young, Primates, in S. B. Hedges and S. Kumar, The Timetree of Life, Oxford University Press, 2009, pp. 482-486.
"A partial fossil was found near Nakali, Kenya." Y. Kunimatsu, M. Nakatsukasa, and 12 other authors, A new Late Miocene great ape from Kenya and its implications for the origins of African great apes and humans, Proceedings of the National Academy of Sciences USA, Dec. 2007, vol. 104, no. 49, pp. 19220-5.
"Gorillas split off around 7 million years ago." S. L. Robson and B. Wood, Hominin life history: reconstruction and evolution, Journal of Anatomy, April 2008, vol. 212, no. 4, pp. 394-425.
"That ancestor enjoyed considerable success in its day, spawning almost 2 dozen separate identifiable human-like hominins." Table 5 of Robson and Wood, Hominin life history: reconstruction and evolution.
"One survey puts elphants and whales are 1.3x and 1.8x respectively." G. Roth and U. Dicke, Evolution of the brain and intelligence, Trends in Cognitive Sciences, vol. 9, no. 5, May 2005, pp. 250-257.
"A dramatic process of brain enlargement in our past began approximately two million years ago." M. A. Hofman, Human brain evolution: design without a designer, Heredity, vol. 20, 2007, pp. 62-67.
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