There were many important players on my journey to the answers.

world journey
 

 

ARDI

Early Upright Posture

To help inform the answers, I needed to understand how we got to Homo sapiens in the first place. Ardi was a key link in our lineage from our common ancestor with the chimpanzees to the first human species which was probably Homo habilis. Ardi is the nickname for Ardipithecus ramidus ("root ground ape"). This famous fossil was reported by Tim White in 1994 after its discovery in Ethiopia. It is thought by many to be the earliest hominid in the line to Homo sapiens, although Sahelanthropus tchadensisOrrorin tugenensis, and Ardipithecus kadabba are also contenders for that distinction. Ardi is about 4.4 million years old. She lived mainly in the trees, helped along by her opposable big toe, but was also able to walk upright between the trees. She had a small brain, closer to the size of a chimpanzee, and didn't make tools. She provided compelling evidence that bipedal upright posture proceeded the development of our large modern brain.

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Aubrey de Grey

1963 - Present

The Methuselarity

Aubrey de Grey is the Chief Science Officer of the SENS (Strategies for Engineered Negligible Senescence) Research Foundation. He is also a faculty member of Singularity University. His research is on regenerative medicine and his focus is on processes to slow or reverse the aging process. He has coined the term "Methuselarity" which is defined as the point at which our ability to reduce the effects of aging exceeds the aging process. At that point, human life expectancy will be almost unlimited. This is different from the "singularity" popularized by Ray Kurzweil, but is related to it in that the singularity once achieved will hasten our progress in science and technologies important to achieve the Methuselarity. One of those technologies is genetic engineering which may be key to slowing or reversing aging, although as Aubrey de Grey's research shows, there will be other factors as well. Certainly if the Methuselarity is achieved, it profoundly alters Homo sapiens.

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Bill Joy

"...we are on the cusp of the further perfection of extreme evil..."

1954 - present

Bill Joy is the co-founder of Sun Microsystems. He is a computer scientist noted for major software developments at Sun. After leaving Sun Microsystems he became a venture capitalist.

His relevance here is related to the famous essay he published in Wired Magazine in 2000 entitled, "Why the Future Doesn't Need Us." In this article he warns that certain emerging technologies, including genetic engineering, artificial intelligence and nanotechnology are potentially worse for humanity than weapons of mass destruction. His proposed solution, "voluntary relinquishment" or voluntary agreement not to pursue these technologies has prompted some to label him a "neo-Luddite."

He is one of a long list of notables that I have cited who are warning us particularly against the dangers of artificial intelligence. The others cited are Stephen HawkingVernor VingeShane LeggStuart RussellMax TegmarkNick BostromJames BarratMichael AnissimovElon Musk, and Irving Good.

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C. Owen Lovejoy

1943 - Present

Why Do We Walk Upright?

 C.Owen Lovejoy is an anthropologist at Kent State University. He is best known for his work related to pre-Homo fossils, particularly Ardi and Lucy. Much controversy surrounds various theories as to why these early species developed upright posture and gait at this time. Lovejoy's explanation is that in our shift from primarily tree-dwelling animals to ones requiring longer travel distances each day to find food, upright posture enabled the male forager to carry back more food from each outing with his freed-up upper limbs. Further, it enabled the female to transport more than one infant at a time enabling more frequent child-bearing. This also precipitated the beginning of the nuclear family and long-term male/female bonding since a male would be less likely to spend long periods away from the female searching food if there was concern about female loyalty.

Other possible explanations for bipedality are discussed including safety from large cat predation, safer conflict resolution, and better heat dissipation. I am not personally convinced that we ever will really know the answer, but I am convinced from the perspective of a physician that upright posture has caused us more problems than it solved. I like the explanation attributed to a Tibetan scholar: "A sense of humor."

To me, this difficulty nailing down the reasons we evolved bipedality is illustrative of a larger issue in studying evolution: not all features selected by natural selection necessarily lead to long-term benefit for a species. In fact, since over 99% of all species have gone extinct, it raises the question whether Darwinian natural selection is a short-term rather than a long-term process. This may apply to the answers.

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Carl Linnaeus

1707 – 1788

Linnaeus

A Classification Junkie

Did King Philip Call Out For Good Soup? This is one of the many mnemonics people use to remember the hierarchy of the classification of living organisms: Domain,  Kingdom,  Phylum,  Class,  Order,  Family, Genus,  Species. This classification, used world-wide for centuries in some form and still the basis for the current tree-of-life classification was originally constructed by Carl Linnaeus, a Swedish biologist and physician. He is thus known as "the father of modern taxonomy." Although this basic classification schema is used today, it has changed somewhat since Linnaeus' description as more precise knowledge of living organisms has developed. For example, the highest level, Domain, wasn't added until 1990 to separate all plants and animals (Eukarya) from Bacteria and Archaea—latter two types of organisms not known to Linnaeus.

The premise of this book is that whatever comes after Homo sapiens will be a species in the genus Homo.

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Charles Darwin

1809 – 1882

Darwin

Survival of the fittest

This book is about the next species after Homo sapiens. The major question is how this species will emerge with secondary questions regarding the timing of this event and the nature of the new species. Charles Darwin is the prime character in describing the prime candidate for the "how." Up until today, for the billions of years that we have had life on Earth, new species have appeared through a process we call evolution. Evolution consists of two processes: 1) Random genetic changes to a living organism and 2) Natural selection. It is Charles Darwin that is generally credited with proposing the second of these processes in his historic book published in 1859 On the Origin of Species. At about the same time another naturalist, Alfred Russel Wallace, had proposed essentially the same thing.

 

At the time of Charles Darwin's life, it was generally recognized that all living organisms, categorized into different species, had variations within these species that appeared spontaneously over time. The genome and the exact genetic mechanisms underlying these variations were not known. However, Darwin observed that individuals with certain variations tended to succeed in propagating future generations while others did not. In his seminal publication, he attributed this success to a process he called "natural selection"—characterized as "the survival of the fittest." That is, there is something in the environment that "selects" certain variants of organisms to succeed and others to fail. Regardless of what caused the variation within species, there was something about certain characteristics that enabled some of the organisms to thrive or better adapt to natural conditions in the environment. Specifically, it enabled them to have more offspring. Those environmental conditions could be almost anything such as climate, food and water sources, predators, competitors for food, infections, geology and other physical features and many more. The genetic variations in the organisms are thus reflected in their ability to adapt to these natural conditions; such as the ability to survive in the particular climate, ability to avoid predation, ability to be a predator, good digestion, better metabolism, resistance to infection, smarter brains, ability to attract mates and many more. In essence, natural selection enables certain individuals with certain characteristics to procreate more than individuals without those characteristics, thus causing that species to survive and ultimately to evolve.

Although natural selection is a primary process in evolution, it is incomplete as an explanation for how new species emerge in the process of evolution. Speciation is more complicated than that.

Evolution by Darwinian natural selection or Darwinian evolution is one of five major mechanisms explored in this book that could lead to the creation of our successor species. The other mechanisms are catastrophe, genetic engineering, electronic evolution and robotics.

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CRISPR

Clustered Regions of Interspersed Palindromic Repeats. 

The Swiss Army Knife of Genetic Engineering

Quite a mouthful!  

For decades, researchers have observed a strange sequence of DNA nucleotides at the end of some bacterial genes—which is what the term CRISPR describes. At first they thought this was just junk DNA. However in 2005, it was shown that a part of this odd-looking sequence actually corresponded to a piece of the DNA of certain viruses that can infect these bacteria. Subsequent research showed that this was not junk, but rather an effective defense system of the bacteria against these viruses. The CRISPR part of the genes actually create RNA molecules that in conjunction with a protein called Cas9 cuts up the invading virus DNA and destroys it. (CRISPR is sometimes referred to as CRISPR/Cas9). Cas9 is an enzyme called a nuclease that actually does the cutting. The CRISPR part of the system tells the Cas9 part where to do the cutting.

Eureka! It became apparent that if one could change the CRISPR sequence with some DNA editing, one would have a general-purpose tool that could cut any DNA anywhere by using the modified CRISPR to direct the Cas9 enzyme. That’s exactly what has now happened. Previous to CRISPR, if a researcher wanted to replace a bad gene in an organism, he or she could identify a good gene somewhere, cut it out and splice it into recombinant DNA with a vector and then insert it into cells with the bad gene. The problem was that the scissors used to “cut out” the good gene and splice it into the recombinant DNA was not a simple tool. It was labor intensive, took months to years to make for any given target gene, was expensive, and was subject to error. Previous tools included zinc finger nucleases and TALEN

CRISPR/Cas9 changes all of that. It can be set up cheaply in just a few weeks for virtually any gene. Suddenly, a tool had been found that in less than a year’s time since its discovery was being used in hundreds of different types of organisms for myriads of genetic engineering experiments. Some have called this the Swiss army knife for genetic engineering and gene therapy.

CRISPR/Cas9 is an amazing tool. You can set it up to cut out and splice any gene quickly. You can purchase a kit on-line to do that for $65. Since many genetic disorders are caused by multiple gene mutations, CRISPR/Cas9 can be set up to deal with multiple genes simultaneously. It can be used in somatic cells, stem cells and germline cells. Animal models of human diseases can be created in a matter of weeks rather than months to years required with previous methods. New companies are sprouting up to market commercial uses of CRISPR. Patent wars have already begun over its ownership. The potential uses are limited only but imagination.  CRISPR was named Science Magazine’s 2015 “Breakthrough of the Year."

Genetic engineering is one of the five pathways I explore in detail that is relevant to the possible answers.

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Elizabeth Kolbert

1961 - Present

The Sixth Extinction

There have been five times in the history of life on earth when over 50% of all living species have gone extinct over a relatively short period of time—evolutionarily speaking. The most recent was about 66 million years ago when a bolide collided with Earth in the Yucatan Peninsula and wiped out the dinosaurs and most other species.

Elizabeth Kolbert, in her book The Sixth Extinction: An Unnatural History, argues that we are probably in the midst of a sixth extinction now. If so, what does that mean for the future of Homo sapiens? What about other catastrophes such as a massive volcano or a nuclear holocaust? Do these simply wipe out today's humans—never to return again; or is this a possible pathway to our successor species?

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Ernst Mayr

1904 - 2005

Species and Speciation

Before one can consider the next species following Homo sapiens, it is first necessary to have some idea as to what we mean by the word "species" and how new species develop—what we call "speciation."

Ernst Mayr dominated this discussion for most of the 20th century. He was the foremost taxonomist of that period. His definition of "species" involving natural interbreeding populations within an ecological niche stressed reproductive isolation as a key part of the definition. That is, the inability to breed with other closely related species was necessary in defining a species. He also developed key concepts of speciation related to natural barriers to interbreeding—what we call allopatric speciation. His theories were widely accepted for most of the century. However, by the end of the 20th century, multiple competing definitions of both species and speciation have been developed with the advent of greater understanding of the genome and mechanisms of genetic variation as well as more complete and precise observations of species in their natural environment.

This has led to what we now call the "species problem" in trying to get agreement on exactly what constitutes a species and when to lump or split groups of similar organisms into one or more species. There is ongoing debate as to whether species are "real" in the sense of having some existential observable external reality versus being arbitrary concepts in the minds of Homo sapiens. All of these issues are discussed in the book. One cannot talk about a successor to Homo sapiens without first agreeing on what a species is and understanding how speciation occurs.

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Eugene E. Harris

1966 - present

The Chimps are in Our Genes

Our closest living relatives are the bonobos, in the same genus as chimpanzees. Eugene Harris, an anthropologist at City University of New York, takes us through the science of genomics and the techniques we now have to better understand our evolution. His book Ancestors in our Genome, provides a clear understanding of our evolutionary history particularly as it relates to the past 15 million years when the great apes emerged and ancient humans evolved into modern humans. Understanding this history informs our possible pathways to our next evolutionary event.

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Gregor Mendel

1822-1884

mendel

 Inheritance

Gregor Mendel was an Augustinian friar at St. Thomas' Abbey in Czechoslovakia. At the time of his experiments in the mid-1800s, traits in children were thought to be inherited by "blending" those of the parents. Mendel did meticulous experiments with peas to disprove that notion. Instead, he showed that various characteristics, for example pea color and pea shape, were inherited discreetly and independently according to rules of dominant and recessive inheritance. He showed that there were two types of peas showing any dominant trait:  purebred and hybrid. Peas showing the recessive trait were always purebred for that trait. When cross-breeding a purebred dominant plant with a purebred recessive plant, all offspring showed the dominant trait. However, when crossbreeding two of these offspring, three-quarters of the subsequent offspring would show the dominant trait and one-quarter would show the recessive trait. There was never any "blending" of the traits in the offspring. He determined from these and other experiments that each trait had two forms of discreet units of inheritance: a dominant unit and a recessive unit. Hybrids always appeared to have the dominant trait, but still were able to pass on the recessive unit to one-half of their offspring.

Mendel's rules of inheritance were largely ignored, ridiculed and even forgotten during his lifetime. It wasn't until the early 1900s that his work was re-discovered. The "units" of inheritance were then given the name of "genes" by the Danish botanist, Wilhelm Johannsen. These genes were contained in particles called "chromosomes" contained in the nuclei of Eukaryote organisms which include all plants and animals.

We now know that Mendel's purebreds were homozygous for the dominant trait whereas his hybrids were heterozygous for the trait. Since both the heterozygous and homozygous dominant plants appear to have the dominant trait, we call this appearance the "phenotype" of the plant. Plants having the recessive phenotype were always homozygous for the recessive trait. The genotype describes the actual genes so that the purebred dominant phenotype has a genotype containing two copies of the the dominant geneone from each parent. The hybrid dominant phenotype would have one copy of each gene type, again one from each parent. The recessive phenotype would always contain two copies of the recessive form of the geneone from each parent. Each of the genetic traits is now called an "allele" in the genome.

Today we call this type of inheritance Mendelian inheritance or Mendelian genetics. Twentieth century statisticians, when reviewing Mendel's publications, basically concluded that his results might have been too good to be true. They seemed fudged to prove Mendel's theories rather than reflecting the normal range of error and variation usually found in natural experiments. That is, statistically speaking, mating two hybrids would not always give the exact ratio of 3/1 in offspring phenotypes as Mendel's data showed, but rather by random chance would have various results around those values. None-the-less, Mendel's ratios are correct and his basic rules still apply generally in genetics. But as you will see in reading the chapter on genetics in the book, this greatly oversimplifies how our genes work and is even somewhat misleading.

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Henry Markram

1962 - present

Blue Brain

The key differentiator of Homo sapiens from all other species both living and extinct is our superior brain. In looking to the future, certainly brain related functions played a huge role in my evaluation of possibilities related to the answers.

Henry Markram is a neuroscientist and Professor at the École Polytechnique Fédérale de Lausanne in Switzerland. His Blue Brain Project is one of the preeminent studies of the mammalian brain with the goal of completely simulating the brain in a computer. The Blue Brain Project subsequently became the core of a European €1 billion 10-year initiative to study the human brain called the Human Brain Project. The Human Brain Project was launched in 2013. A parallel project, funded by the Obama administration in the US is called the BRAIN Initiative (Brain Research through Advancing Innovative Neurotechnologies), also launched in 2013. Markram has boldly predicted that complete understanding of the human brain will be achieved by 2023. He recently published the simulation of a small portion of a rat brain. Although a remarkable achievement, it fell far short of his previous prediction to simulate a full rat brain by 2014. This failure to come anywhere close to achieving his projections has led many neuroscientists in Europe to question the likely success of the Human Brain Project as well as Markram's leadership of it.

Understanding the human brain and its genetics is a major focus of multiple scientific and technologic approaches to not only solving many neurologic disorders, but to fundamentally altering Homo sapiens as a species. It is central to achieving the singularity and other futuristic predictions regarding our species and research in this area heavily imbued the journey. One key focus of these studies is to be able to completely understand the "connectome" of various species. The connectome is a description of all of the neuron connections in a brain. So far, the only species in which the complete connectome has been published is that of a worm called C. elegans. This worm has 302 neurons in its brain. Progress is being made in describing the connectome of a fish called the zebrafish as well as the mouse.  The zebrafish brain has 100,000 neurons and the mouse brain has 71 million neurons. The human brain has 85 billion neurons! We have a long way to go to get from simulation of 302 neurons to 85 billion and hopefully, both the Human Brain Project and the BRAIN Initiative will help get us there.

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Iam Tattersall

1945 - present

The Rickety Cossack

Ian Tattersall is a paleoanthropologist and the curator emeritus of the American Museum of Natural History in New York City. He has studied and written extensively on the origins of Homo sapiens. His book The Strange Case of the Rickety Cossack, is both educational and entertaining. He reviews in great detail the numerous twists and turns in trying to piece together the fossil evidence around the world related to our origins. The story is neither pretty nor clear. It is a tale that involves almost as much variation in the backgrounds of the scientists as it does in the sciences being studied. We have paleoanthropologists, paleontologists, systematists, anatomists, evolutionary psychologists, cultural anthropologists, neuroanatomists, taxonomists and paleogenomicists all vying for attention. There were many conflicting reports based on fragments of bones found in caves, sediments and ancient seabeds all over the world. These differences sometimes led to petty personal conflicts, shouting matches at professional meetings and even life-long feuds. There was claim jumping at archeological sites, political intrigue at the highest levels of governments, the Piltdown man fraud, and lawsuits. There were lots of Leakeys. Theories of our origin ranged from narrow straight-line evolutionary paths to complex matrices leading to multiple independent lineages reflected in our current cultural and geographic diversity. Finally, the list of purported genera and species in the Homo lineage is as long and sometimes as ephemeral in the fossil record as they are in the Homo sapiens’ literature.

Ian Tattersall is one of many anthropologists that guided me on the journey. The diversity of possible paths and the uncertainties surrounding them in the fossil record were important factors informing my conclusions regarding the answers. They stimulated me to search broadly.

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Jean-Baptiste Lamarck

1744 - 1829

Soft Inheritance

lamarck

Jean-Baptiste Lamarck was an eminent French biologist and taxonomist. He published an influential theory of evolution, one component of which claimed that attributes that an organism acquires during life are passed on to progeny. Ernst Mayr called this "soft inheritance" to differentiate it from "hard inheritance" governed by genetic processes. So-called Lamarckian evolution was pretty well debunked by the early 20th century to be replaced by Darwinian evolution and Mendel's theories of dominant and recessive inheritance through genes.

It turns out that Lamarck was not entirely wrong. We now know that some epigenetic processes are influenced by the environment and that some of the resulting epigenetic alternations affecting gene expression may be passed on to progeny. Further, germline genetic engineering which is "acquired" during an organism's lifetime is certainly passed on to progeny. Of course Lamarck was not aware of the epigenome nor of the possibility of genetic engineering.

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John Markoff

1949 - present

Machines of Loving Grace

John Markoff is a journalist and senior writer for the New York Times. His recent book Machines of Loving Grace, describes the current tension in robotics between Artificial Intelligence (AI) and Intelligence Augmentation (IA). That is, should we be designing robots to replace humans (AI) or assist humans (IA) when it comes to tasks requiring decisions, advice and other cognitive functions.

The broader issue of robotics is one of the main pathways to the answers researched in the book. The other pathways are catastrophe, natural selection, genetic engineering and electronic evolution.

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Katherine Pollard

"...you do not need to change very much of the genome to make a new species.”

Katherine Pollard heads the Pollard Group at the Gladstone Institutes at the University of California, San Francisco. She is Professor of Biostatistics and applies her skills to statistical analyses of the genomes of humans and other species.

One of the seminal questions I pursued in my research is to find out exactly what makes Homo sapiens different from our predecessor species. That might point the way to our future evolution into a successor species. Since all of our direct predecessor species are extinct, we have only fragmentary fossil comparisons. We're not even sure exactly which species was our direct predecessor. It was probably Homo heidelbergensis or Homo erectus or some close relative of one of those.

The best way to answer this question would have been to compare the genomes of Homo sapiens to the predecessor. Unfortunately, we have not yet been able to recover any DNA from the possible predecessor fossils. Svante Pääbo and his team at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany has been able to recover and analyze the genomes of two other extinct human species: Neanderthals and Denisovans. Although their comparison to Homo sapiens is informative, since neither of these species is in our direct lineage, it does not fully answer the question.

Katherine Pollard and her team have taken another genome related approach to answering this question. We can do genome analyses on living species that share common ancestry with Homo sapiens and compare them to our genome. Using massive computer power and statistical analyses we can infer a great deal from such comparisons. Genetic mutations are random so there is a baseline number of expected changes that should occur throughout the genome of all species. However, since natural selection is operating on those changes, some parts of the genome will show more changes than others because those changes conferring a beneficial effect will be selected to be passed on to future generations. These so-called “accelerated regions” tell us a lot about evolution and speciation.

Katherine Pollard and her team did such a genome comparison. She found that there is a very small part of the human genome that has undergone the most rapid changes since we split from the chimpanzees. That region is called HAR1 (human accelerated region 1). HAR1 consists of just 118 nucleotides (out of three billion in our genome). By looking at these same nucleotides in the genomes of chickens, chimps, and other species, she could determine that those same nucleotides were stable in the previous 300 million years in those other species. Something happened in the 5.4 million years since we split from the chimps to cause the changes in these particular nucleotides to be selected. Those changes must be related to the emergence of Homo sapiens. It turns out that HAR1 is important in regulating the genes that cause the human brain to develop the convolutions in our neocortex. It is these convolutions which provide the enormous increase in surface area of our brain enabling much more complex behavior. They are epigenomic changes.

There were some other HARs that Dr. Pollard examined as well. These are related to our linguistic ability and our increased manual dexterity—two other key differentiators of our species. Thus, it appears that Homo sapiens emerged because of a relatively small number of genetic mutations in a relatively short period of time. As Dr. Pollard states, “In other words, you do not need to change very much of the genome to make a new species.” This was a key clue to looking for the answers.

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Kevin de Queiroz

The Species Problem

Kevin de Queiroz is a research zoologist at the Smithsonian National Museum of Natural History in Washington, DC.

In order for me to talk about the next possible species in our lineage, I had to be clear on exactly what I meant by the word "species." Scientists from all related fields have struggled for centuries to agree on such a definition. The debate over what exactly should define a species dates all the way back to the days of Plato and Aristotle. One would think that with modern technology, particularly the ability to study the genomes of living species, that this debate would have been settled by now. It hasn't. We still have what is called the "species problem." In our recent history, prominent scientists like Ernst Mayr and Theodosius Dobzhansky have all published their views on this topic. John Brookfield, Professor of Evolutionary Genetics at the University of Nottingham summed it up nicely: “The essence of the ‘species problem’ is the fact that, while many different authorities have very different ideas of what species are, there is no set of experiments or observations that can be imagined that can resolve which of these views is the right one. This being so, the ‘species problem’ is not a scientific problem at all, merely one about choosing and consistently applying a convention about how we use a word. So we should settle on our favorite definition, use it, and get on with the science.”

So that is exactly what I did. Kevin de Queiroz has published what he believes is the solution to the species problem. His definition goes back to fundamental principles that can incorporate multiple factors that others have used to define species. The definition is as follows: "A species is a segment of a separately evolving metapopulation lineage."  I realize that the typical reader will not have any idea what this definition means, but I assure you that I have explained it in the book in easily understandable terms and have applied it to the possible answers.

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Lucy

The Missing Link?

Lucy is arguably the most famous fossil of all time. She was discovered in Ethiopia in 1974 by Donald Johanson. Her species is Australopithecus afarensis (Southern Ape from Afar). She lived 3.2 million years ago and often is called the "missing link." She is probably in our direct lineage between Ardi, who lived 4.4 million years ago, and our Homo genus ancestors, who emerged about 2 million years ago.

Like Ardi, Lucy walked upright. However, unlike Ardi, she did not have an opposing big toe and was more "human-like" in that regard. Therefore, she spent a lot more time on the ground and relatively little in the trees. Her brain, however, was still small and her abilities were ape-like.

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Miguel Nicolelis

1961 - present

Brainets

The brain is the differentiator of humans from all other species. Yet there is still much we do not know about it. Speculation in the book envisions the possibility of silent communication between future humans via "brain wave" detectors in a manner analogous to the way in which an electroencephalogram (EEG) today can detect electrical signals in a brain. Could such a biological detector ever evolve? Could an artificial one be somehow embedded in future humans? Could the receipt of such a signal be interpretable by another brain? All speculation of course. However, we have evolved other biological sensors equally complicated such as the retina for electromagnetic wave detection, the cochlea for sound wave detection and the olfactory system for chemical substance detection. Further, our brain has a magnificent capability to recognize patterns in signals so receivedfar better than any artificial detection systems we have developed.

Miguel Nicolelis is providing us with a proof of concept of this speculation. He has attached electrodes into the brains of monkeys and has shown that a monkey is capable of manipulating a distant robotic arm based on signals received from these electrodes. More amazing, he has networked multiple monkeys with such attached electrodes so that they could receive the signals from each other. Monkeys using these so-called "Brainets" are able to cooperate in certain tasks leading to food rewards better than monkeys not so attached!

Equally amazing are experiments in humans to demonstrate what are called brain-to-brain interfaces (BBI). In one such experiment, signals detected in an EEG of one individual are transmitted to a computer. The computer signal is communicated to a remote computer location where this second computer is attached to a signal generator, called a Transcranial Magnetic Stimulator, attached to the skull of a second individual. The second individual was able to understand certain limited communications from the first individual in this manner!

One of the speculations regarding the possible future singularity envisions an artificial superintelligence consisting of networked humans and computers through the Internet creating a so-called "Global Brain." Are Dr. Nicolelis' monkeys and BBI also proof of concept for this?

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Paul Allen

1953 - present

The Singularity Isn't Near

Paul Allen is the co-founder of Microsoft with Bill Gates. He owns the Seattle Seahawks and the Portland Trail Blazers. His relevance to the journey, however, is that he is the founder and chief benefactor of the Allen Institute for Brain Science.

Understanding the possible future of Homo sapiens, including possible speciation events investigated in this book, is highly informed by the study of two major biological systems: the genome and the brain. The Allen Institute for Brain Science is playing a major role in brain studies. The Allen Mouse Brain Atlas is one of several on-line tools made available on the Internet by the Institute. It is an on-line resource to researchers studying the connectome of the mouse brain and gene expression in the mouse brain bringing together research findings from around the world. Studies of the mouse brain provide valuable insights into the human brain because of similarities of the mammalian mouse brain as well as the mouse genome to the human brain and human genome. Experimentation can be performed on mice and other animal models that are not ethically possible on humans.

I also met up with Paul Allen in the journey through an article co-authored by him and another computer scientist, Mark Greaves. The article is "The Singularity Isn't Near" which is a rebuttal to some of the projections of Ray Kurzweil.

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Paul Berg

1926 - present

Recombinant DNA

Genetic engineering is one of the major tools explored in the book that could influence the possible future speciation of Homo sapiens.  

Paul Berg, who received the Nobel Prize in Chemistry in 1980, inaugurated the era of genetic engineering with his seminal work on nucleic acids, the building blocks of DNA. In the early 1970s, he and his colleagues at Stanford showed that it was possible to selectively take a portion of DNA from one organism and insert it into the DNA of another organism. This was the first demonstration of the creation of what is called recombinant DNA.

Based on this work, in 1973, Herb Boyer and Stanley Cohen experimented with common bacteria found in all humans, E. coli. These bacteria have structures in their cells called plasmids that are small circular pieces of DNA, separate from the chromosomes, which produce proteins in bacteria. They play a role in a small number of functions, including antibiotic resistance. Boyer and Cohen were able to transfer plasmids from one strain of E. coli having resistance to a single antibiotic into another strain that did not have that resistance. After transfer, the receiving strain subsequently had resistance also. This showed that the genes from one strain of E. coli could be transferred to another strain.

What really got the ball rolling, however, was when they showed they could selectively cut out the part of the plasmid containing the resistance gene and patch it into the plasmid of another strain of E. coli thus creating recombinant DNA with the resistance gene. This is the key to genetic engineering: the ability to isolate a small segment of an organism’s DNA that contains a particular nucleotide sequence of interest, to make many copies of that DNA segment, and then splice or patch that segment into some vector to create recombinant DNA. The vector is then used to enter the target or host organism. In this first case cited above, the vector was a bacteria plasmid. Viruses are commonly used as vectors as well. Since the recombinant DNA gene was from the same species as the host organisms, the process is called cisgenic.

Next they created a recombinant DNA plasmid that contained the genes for resistance to multiple antibiotics by patching genes from a different species of bacteria, Staphylococcus aureus, into a single E. coli plasmid, transferred that plasmid to other E. coli which then not only became resistant to all the antibiotics, but also conveyed those same traits on to future generations of that strain of E. coli. This showed that genes from a different species of bacteria could be transferred to host bacteria. When genes are passed across species, it is called transgenic. Genetic engineering was now underway.

Finally they demonstrated that they could create an E. coli recombinant DNA plasmid that contained a gene from a toad! And the toad gene functioned in all future generations of that strain of E. coli. This showed that transgenic engineering could occur virtually unconstrained by species and set the stage for human genetic engineering.

Genetic engineering is one of five major pathways to a future future human species explored in the book. The other pathways are catastrophe, natural selection, electronic evolution and robotics.

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R.A. Fisher

1890 - 1962

Modern Evolutionary Synthesis

fisher

In the mid-1800s Gregor Mendel debunked the then current thinking of heredity as a process of blending the traits of the two parents (see Jean-Baptist Lamarck). Instead, heredity was driven by individual units (later called genes) that contained dominant and recessive variants. These units acted independently and recessive traits would be carried across generations and reemerge visibly (later called phenotype) when in the homozygous state. There was no blending of the dominant and recessive variations.  

In 1859, Charles Darwin published his revolutionary concept of evolution by natural selection. This concept explained how environmental factors worked against the variations within species leading to the eventual emergence of new related species. Although Darwin overlapped with Mendel, he was unaware of Mendel's work and did not understand the mechanism of variation within species nor how that variation changed over time.

To many in the early twentieth century, there seemed to be an incompatibility between Mendelian inheritance and Darwinian evolution. How could the gradual evolution of species through natural selection be explained by genes that worked in step-wise, all-or-none gradations?  

Sir Ronald A. Fisher, an Englishman, was a statistical genius who laid the foundations for modern experimental design. He was knighted in 1952. His contributions to biostatistics are foundational. He applied strict mathematical principles to Mendelian genetics to quantify and solidify the principles of natural selection and to explain how blended phenotypes can arise from what he called "particulate" inheritance. His work, along with J.B.S. Haldane and Sewall Wright is the basis for the field of population genetics. This work was later expanded by the geneticist Theodosius Dobzhansky into the modern evolutionary synthesis. This grand synthesis brought together key concepts of Darwinian evolution, Mendelian genetics, genetic drift and paleontology.

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Sally McBrearty and Alison Brooks

The Revolution that Wasn't

Tracing the origins of Homo sapiens through the fossil record is fragmentary. First of all, the fossils themselves are fragmentary, containing only some of the bones of any given specimen. Only a small number of fossil specimens is found for any given species and these are often spread out in different sites and come from different times. Finally, there is significant variation within any given species (look at today's humans!) so any small sample of individuals can be misleading when extrapolating to the entire population. Therefore, paleontologists look for clues in other ways that might reflect on the culture, capabilities and even the appearance of any given extinct species. These include looking at other artifacts that are found adjacent to the fossils like tools, pottery, jewelry, wall engravings, other animal fossils, and other clues.

Sally McBrearty and Alison Brooks have done just that regarding the years leading up to the emergence of Homo sapiens and have described this work in their beautifully written article in the Journal of Human Evolution"The Revolution that Wasn't: A New Interpretation of the Origin of Modern Human Behavior."

They demonstrated that the culture and behaviors we associate with modern humans (us!), like wall painting, jewelry making, fishing and tool-making, did not just appear suddenly. Instead, they emerged over a long period dating from 280,000 years ago through about 50,000 years ago. These cultural changes were associated with a number of our predecessor species as well as our own in our transition from archaic humans to modern humans.

This work makes it clear that there wasn't some abrupt, sharp delineation between pre-Homo sapiens and Homo sapiens. Rather, there is a continuum of changes that evolved over two hundred thousand years or more. Will this also be true regarding our evolution to a successor?

Sally McBrearty is a professor and head of the Department of Anthropology at the University of Connecticut. Alison Brooks is Professor of Anthropology and International Affairs; Director, Center for the Advanced Study of Hominid Paleobiology at the Elliott School of International Affairs at George Washington University in Washington, DC.

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Scott Blois

1919 - 1988

Common Sense

Marsden Scott Blois, MD was the Chairman of the Section on Medical Informatics at the University of California, San Francisco School of Medicine. His relevance to the journey is two-fold. First, I knew him personally while on the faculty at UCSF. He was one of the founders of the American College of Medical Informatics of which I am a founding member. More importantly, Scott is the author of an important journal article describing a key concept that I used in the book. The article, published in the New England Journal of Medicine in 1980 was entitled, "Clinical Judgement and Computers."

blois

The figure to the left is taken from this article. The funnel is meant to show the decreasing cognitive span of a physician during the process of making a diagnosis regarding a patient. At first, represented by point A in the figure, any diagnosis is possible. The physician, with his or her general knowledge of medicine and of the world in general and the ability to interact with other humans by talking with them (taking a history), examining them and observing their behavior must narrow down the huge number of possibilities to a reasonably small number called the differential diagnosis. Selecting from the smaller number of choices in the differential diagnosis is represented by point B in the figure. The process at point B to get to the correct diagnosis often requires the use of laboratory tests and other diagnostic procedures and very specific detailed knowledge of the narrow disease spectrum. Blois’ contention was that physicians are far superior to computers at point A whereas computers, if programmed properly with the right rules, are superior to physicians at point B.

The funnel could represent any domain of knowledge, not just medicine. Somehow, the human brain is born with the capability to get to point A just by living in the world. It is common sense. The goal of artificial intelligence is to move point B as close as possible to Point A. When Artificial General Intelligence is achieved, Point B will be at Point A and when the singularity and Artificial Superintelligence is achieved, Point B will be to the left of Point A.

The above discussion is part of the journey regarding electronic evolution, one of the major paths explored regarding the answers.

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Singularity

When Artificial Intelligence Exceeds
Human Intelligence

In astrophysics, a singularity is the point at which gravity becomes infinite as in a black hole or at the point of the Big Bang. That is not the kind of singularity discussed in this book. Rather, the singularity in this book refers to a potential future phenomenon wherein artificial intelligence (AI) reaches the level of human intelligence and then "explodes" into a process of ever increasing intelligence far exceeding that of humans.

If and when such a singularity is reached, it has profound implications for the future of Homo sapiens and calls into question the essence of what it means to be human, the future of our species and even our very existence going forward. Clearly I needed to sort out science from science fiction in reviewing the literature on this possible phenomenon.

The first person to apply the term singularity as a serious possible future human condition was the great mathematician, John von Neumann. In the 1950s he defined the singularity as the moment beyond which "technological progress will become incomprehensively rapid and complicated."

Irving J. Good was a British mathematician who worked with Alan Turing at Bletchley Park during World War II to decrypt German codes. In 1965, he said, “The survival of man depends on the early construction of an ultraintelligent machine.” He further said, “Let an ultraintelligent machine be defined as a machine that can far surpass all the intellectual activities of any man however clever. Since the design of machines is one of these intellectual activities, an ultraintelligent machine could design even better machines; there would then unquestionably be an ‘intelligence explosion’ and the intelligence of man would be left far behind…Thus the first ultraintelligent machine is the last invention man need ever make, provided the machine is docile enough to tell us how to keep it under control.”

Vernor Vinge is a mathematician and computer scientist. In 1993, at a NASA conference, he described the singularity as the point at which we have created a computer with intelligence greater than human intelligence. At that point, he said, "the human era will be ended."

Ray Kurzweil has taken on the mantle of popularizing the discussion of the singularity and bringing it to near cult-like status. He is a graduate of MIT and has pioneered in the development of numerous technologies including voice recognition, optical character recognition and electronic keyboards.  His books The Singularity is Near and How to Create a Mind are must reads for anyone interested in understanding the science and technology of the singularity. Kurzweil's premise is based on the fact that technology is increasing at an exponential pace and that we are reaching a critical "knee" in that pace where our knowledge and technology explode. This applies particularly to our ability to understand the human brain and to be able to simulate it entirely in a computer. This, he predicts, will happen by the year 2030. At that point, we will be unable to distinguish computer intelligence from human intelligence. That is, a computer will be able to pass the Turing Test. Further, by using nanobots, tiny computerized robots that can be injected into the bloodstream and populate the brain, we will greatly enhance our brain understanding and capability. These nanobots will allow us to “download” wirelessly all information in our brains into a computer so that basically a computer will be able to “think” like a specific individual human. In essence, a person’s mind will exist in silicon. Since these electronic technologies do not have the physical limitations of our biological brains, they will process information far faster than our slow neurons can. The computer emulations will learn and change their own software accordingly. Thus they will evolvefar faster than natural selection allows our biological brains to evolve. These computer enhancements can be continually uploaded back into the human brain’s nanobots. At this point, the biological and silicon brains will be interchangeable and we will have reached the singularity. That will happen by 2045. The question for me is whether this can be considered our successor species or lead to it.

This is not science-fiction. Kurzweil has co-founded the Singularity University which sponsors legitimate research forums on artificial intelligence, nanotechnology and other other related science and technology topics. People who promote the concept of the singularity are referred to as singularitarians. Kurzweil became Google's Director of Engineering in 2012 and now has the backing of one of our largest companies in furthering his concepts.

Many others, besides Kurzweil, have written extensively on the singularity and have studied its possible consequences. There are many visions as to how this might play out. Nick Bostrom is a Philosophy Professor at the University of Oxford and founding director of the Future of Humanity Institute. He has studied AI extensively and describes what he calls the "crossover point" where the AI computer is able to begin re-programming itself and making itself ever increasingly intelligent. It then becomes a superintelligent computer. Bostrom warns that after the crossover point, we will be unable to control the AI and that it will become an existential threat to humanity. Therefore, we must plan now to attempt to embed software that will insure that the future superintelligent computer will be "friendly" to humans. He warns, however, that such attempts are likely to fail.

James Barrat, another writer on AI, describes the point at which AI equals human-level intelligence, called Artificial General Intelligence (AGI). As Bostrom has predicted, he states that the AGI will quickly cross over into Artificial Superintelligence (ASI) and warns of the same dangers.

Francis Heylighen is a Belgium cyberneticist (a person who studies complex control systems.) He has a somewhat different view of the singularity. Rather than being a single entity, he sees the future ASI to be the result of a gradual evolution to a network of connected humans and computers that collectively have superintelligence. Their super ability will be related to the fact that they are networked through the Internet so that they are virtually everywhere on Earth and are therefore all-seeing and all-knowing. His view is that this distributed model of superintelligence will not be a threat to humanity. This model is called the Global Brain.

There are now multiple groups that have formed organizations whose purpose, at least in part, is to study methods to prevent the existential threats from AI. These include the Machine Intelligence Research InstituteHumanity+The Future of Life Institute, Future of Humanity InstituteOpenAI and the Foresight Institute.

The singularity is discussed at length in the chapter on electronic evolutionone of five major paths considered for the answers. The other paths are catastrophe, natural selection, genetic engineering and robotics.

The singularity surely has had an influence on my thinking about the answers. Its impact will be a surprise to you.

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Stephen Jay Gould

1941 - 2002

The Human Accident

Stephen Jay Gould was an inspiration to me throughout this book. His insights into human evolution were unique and illuminating. The readability of his many books to us lay readers set a bar I wish I could achieve.

He taught me that evolution does not imply progress. He taught me that Homo sapiens is not the epitome or goal of evolution but just one of many branches no more significant than many others. He taught me that Homo sapiens is a random accident that would be unlikely to be repeated even if we could roll back time to the primordial conditions from which we emerged and plant the exact same chemical seeds.

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Svante Pääbo

1955 - present

Genomes of Extinct Humans

Svante Pääbo is revolutionizing our understanding of human evolution. He is the Director of the Department of Genetics of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.

Our ability to sequence the genome has improved by orders of magnitude since the Human Genome Project completed its first draft in 2003. We have learned amazing things since then about today's humans and many other existing species. By comparing our genome with that of chimpanzees, for example, we can learn not only what really makes us different, but when certain events occurred since we separated from our common ancestor 5.4 million years ago. Analyses such as that done by Katherine Pollard has enabled us to determine exactly what changes in our genome caused this differentiation. By comparing the genomes of different humans from different parts of the world, we can trace the history and timings of migrations that occurred thousands of years ago. Genome databases from humans and many other species are creating research opportunities in every biological field.

However, questions about our exact lineage in terms of other human species in the fossil record cannot be determined solely from examination of the genome of living humans. We need to be able to look at the genomes of extinct human species to do that. That has always seemed to be impossible since the tissues containing DNA are not preserved in fossils...until Svante Pääbo figured out how to do it. It turns out that some DNA is preserved in some teeth and bones of some fossilsbut only in minuscule fragmentary amounts. It has taken Pääbo's team years of meticulous process development to be able to extract that DNA, piece it together, and generate the genome of an extinct species. At first this was done only for mitochondrial DNA which is present in higher volume but later was accomplished for the more important nuclear DNA. One of the big problems facing everyone attempting to accomplish this is that in the process of performing the laboratory analyses, contamination of DNA from the researchers and/or fossil handlers has confused the analysis. Microscopic particles from human skin or airborne saliva or other sources can easily contaminate the fossil specimens. This could have occurred anywhere in the handling of the fossils including even at the site at which they were originally discovered. The Pääbo team has developed the methods to detect and eliminate such contamination and has created special "clean" laboratories for these analyses.

So far, the complete genomes of two extinct human species has been determined: Neanderthals and Denisovans. In fact, this genome analysis from the few teeth and bone fragments we have available, is the only way we even know that Denisovans existed and were a species distinct from other humans.

What we have learned from these analyses is amazing! First of all, the DNA from current Europeans contains 1-2% of their DNA from Neanderthals. A similar amount of Neanderthal DNA is contained is today’s Asians. However, no Neanderthal DNA is contained in today’s Africans. Wow!!! That means that Neanderthals did not emerge until the predecessor to Homo sapiens had already left Africa. Neanderthals had separated from an earlier hominin, probably Homo heidelbergensis, at least 400,000 years ago. Since that was before Homo sapiens appeared, the Neanderthals are not in our direct ancestral line. The genome analysis confirms that there was a small amount of interbreeding between Neanderthals and Homo sapiens that must have occurred after “Out of Africa 2.” That is, the Neanderthals split from a more ancient human species that left Africa at an earlier time (Out of Africa 1). Then, since Homo sapiens emerged later in Africa, it was after the Homo sapiens migration from Africa (Out of Africa 2) that the interbreeding occurred. Since Neanderthal DNA shows up in Europeans and Asians about the same amount, it suggests that the interbreeding could have occurred in the Middle East before Homo sapiens spread in the two directions. Similarly, some of today’s Asians and particularly those in Oceania contain as much as 3-6% of their DNA from Denisovans whereas Europeans contain no Denisovan DNA. Native Americans do have Denisovan DNA. This pattern would confirm that Homo sapiens interbred with Denisovans to a small extent while they were on their way to North American through Asia.  Neanderthal DNA is 99.7% identical to Homo sapiens DNA. That’s a lot closer than we are to chimps.

Some of the evidence we’re getting from extinct genomes is making things muddier. Svante Pääbo’s group have recently been able to painstakingly extract enough mitochoncrial DNA from some ancient bones in Spain to cast doubt on the date Homo sapiens diverged from its predecessor. The DNA confirmed that these ancient fossils were Neanderthals. But the striking thing about this is that their age is much older than previously thought indicating that the date that Homo sapiens may have split from our predecessor may be as early as 700,000 years ago rather than 200,000 years ago. This depends on which version of our lineage turns out to be correct. Several alternatives are discussed in the book. To further complicate the timing issue, DNA analyzed from a Neanderthal fossil found in the middle east from about 100,000 years ago contained some Homo sapiens DNA indicating that at least some modern humans migrated from Africa much earlier than thought and interbred with Neanderthals there. The more we are able to tease out DNA from ancient fossils and compare them to a growing database of DNA from living humans around the world, the more complicated our history seems to get. There probably were at least five distinct periods and locations where interbreeding occurred between Homo sapiens and ancientnow extincthuman species.

Hopefully, Pääbo's team will soon be able to extract the DNA for other extinct human species and either further illuminate or further complicate our history.

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Sydney Brenner

1927 - present

 "The Mind of a Worm"

The great differentiator of Homo sapiens is our brain. Much focus in the book is on the future of the brain and/or brain simulations through artificial intelligence. Indeed, much focus in genetics and neuroscience world-wide is in understanding both the genetics and connectome of the human brain.

Sydney Brenner has provided the first major stepping stone in achieving that understanding. He has determined the complete connectome as well as the associated genetics of a worm called C. elegans with its 302 neuron brain. He received the Nobel Prize in Physiology or Medicine for this work. In the cover letter used in submitting the paper for publication, he called his work, "The mind of a worm." He further stated that "There are no other wires, we know all the wires."

Although Brenner's work is a major achievement, it will be quite a leap to scale up from a worm to a human brain with its 85 billion neurons.

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Terry Sejnowski

1968 - present

 The Human Brain in a Computer

Terry Sejnowski is what I would call a singularitarian. He directs the Computational Neurobiology Laboratory at the Salk Institute for Biological Studies in San Diego. His research into neural networks, brain computation, and brain functionality at the synaptic, electrical and chemical levels has made him one of the preeminent neuroscientists in the world. To me, he is one of the many eminent scientists that brings credibility to the singularity notion.  He has pioneered the modeling of brain activity in a computer in exquisite detail.

The following is from his website: "Terrence Sejnowski has turned to computer modeling techniques to try to encapsulate what we know about the brain as well as to test hypotheses on how brain cells process, sort and store information. While other scientists have focused on mapping the physical arrangement of neurons (tracing which cells connect to which), Sejnowski is interested in a more functional map of the brain, one that looks at how sets of cells are involved in processes—from filtering what we see to recalling memories. To collect data on brain function, Sejnowski records the electrical activity of select sets of cells, as well as analyzes thin slices of autopsied brains. He uses that information to create and refine computational models on how the brain stores information for different activities. Through these models, he gets a better understanding of what information different cell types encode, what molecules are needed and how signals move throughout the brain. At the same time, he learns how diseases such as schizophrenia or Parkinson’s might alter these patterns."

Brain modeling, neural networks and the singularity are all part of the journey as described in the chapter on electronic evolution.

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Theodosius Dobzhansky

1900 - 1975

Discontinuities

The groundwork that I had to do before I could explore the answers involved acquiring a basic understanding of what is meant by the word "species" and how we would be able to recognize if and when a new species emerged from Homo sapiens. Much of that groundwork was provided by the great geneticist, Theodosius Dobzhansky. His publication in 1937 of Genetics and the Origin of Species provided a framework for evolutionary biology, called the modern evolutionary synthesis, that is still meaningful today.

He pointed out the apparent paradox that if we were able to assemble all of the organisms that ever existed, it would constitute a seamless continuity making it difficult if not impossible to create a classification system of different species. The fact of the matter is that many types of organisms have become extinctin fact most of them. This has created discontinuities between types of organisms enabling the ability to define species and categorize them.

Nonetheless, evolution is gradual and continuous which complicates my task in defining the answers.

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Victor McKusick

1921 - 2008

The Father of Medical Genetics

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I was a medical student, medical resident and faculty member at the Johns Hopkins School of Medicine in the 60s and 70s. During that time, Victor McKusick was Professor of Medicine there. Must of us, if not all, were in awe of him. He not only knew everything there was to know about human genetics and genetic-related diseases, but he seemed to know everything about a lot of other topics as well. I remember an incident during a time I was doing an elective project in cardiology. I was learning how to use a special device for recording and analyzing heart sounds called a spectral phonocardiograph. One day Dr. McKusick happened by and gave me a few pointers on how to use the equipment. When he left, the head of the laboratory told me that he was the one who had invented the technology!

On Dr. McKusick's days in the clinic, the waiting room would be filled with a mixture of Amish (who had a high incidence of genetic disorders because of inbreeding), dwarfs, and all variety of people with genetic disorders and genetic variations. We now know that of the 3 billion nucleotides that make up the human genome, only 0.1% of them account for all the variation we see in humans. Dr. McKusick studied these variations, published voluminously about them and created in the 1960s a database of all known genetic abnormalities in humans. Because of this work, he is often referred to as "the father of medical genetics."

My path intersected again with Dr. McKusick's greatness during the journey for this book. His database grew over the years and went through 12 book editions. In 1998, it was converted to an online database by the National Center for Biotechnology Information and is now called the Online Mendelian Inheritance in Man (OMIM). Researchers from all over the world contribute to this online resource which is still maintained by the Johns Hopkins School of Medicine. It contains descriptions of over 5,500 medical conditions with a known genetic basis including the detailed nucleotide sequence and chromosome location of over 3,400 gene mutations.

Genetic engineering, one of the main possible pathways to the answers described in the book, depends first on understanding which genes cause which disorders. It starts with OMIM.

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Watson and Crick

  James D. Watson

  James D. Watson

dna
Francis Crick

Francis Crick

"It has not escaped our notice..."

The journey took me into contact with the work of many great people in the history of science as it relates to human evolution. These included Carl Linnaeus, Charles DarwinGregor MendelTheodosius DobzyanskyErnst Mayr, and many others. Perhaps it is James Watson and Francis Crick that represent the seminal turning point in our understanding of this evolution. Their publication of the structure of DNA in 1953 was rewarded with the Nobel Prize in Physiology or Medicine along with Maurice Wilkins. In their publication, they stated, “It has not escaped our notice that the specific pairing we have postulated immediately suggests a possible copying mechanism for the genetic material.” What an understatement! That “possible copying mechanism” revolutionized our understanding of genes. Of course the "pairing" they were referring to is the famous double-helix configuration of DNA. The key to discerning the double-helix structure was based on the x-ray crystallography work of Rosalind Franklin who worked in the laboratory of Maurice Wilkins at Kings College in London. Many feel that Rosalind Franklin deserved to share in the Nobel Prize.


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