David Reich > Quotes

“There was never a single trunk population in the human past. It has been mixtures all the way down.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past

“We geneticists may be the barbarians coming late to the study of the human past, but it is always a bad idea to ignore barbarians.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the new science of the human past

“The extraordinary fact that emerges from ancient DNA is that just five thousand years ago, the people who are now the primary ancestors of all extant northern Europeans had not yet arrived.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past

“Seventy thousand years ago, the world was populated by very diverse human forms, and we have genomes from an increasing number of them, allowing us to peer back to a time when humanity was much more variable than it is today.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past

“The genome revolution has shown that we are not living in particularly special times when viewed from the perspective of the great sweep of the human past. Mixtures of highly divergent groups have happened time and again, homogenizing populations just as divergent from one another as Europeans, Africans, and Native Americans.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past

“Prior to the genome revolution, I, like most others, had assumed that the big genetic clusters of populations we see today reflect the deep splits of the past. But in fact the big clusters today are themselves the result of mixtures of very different populations that existed earlier.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past

“Ten generations back, for example, the number of ancestral stretches of DNA is around 757 but the number of ancestors is 1,024, guaranteeing that each person has several hundred ancestors from whom he or she has received no DNA whatsoever.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past

“As a society we should commit to according everyone equal rights despite the differences that exist among individuals. If we aspire to treat all individuals with respect regardless of the extraordinary differences that exist among individuals within a population, it should not be so much more of an effort to accommodate the smaller but still significant average differences across populations.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past

“So how much Neanderthal ancestry do people outside of Africa carry today? We found that non-African genomes today are around 1.5 to 2.1 percent Neanderthal in origin,24 with the higher numbers in East Asians and the lower numbers in Europeans, despite the fact that Europe was the homeland of the Neanderthals.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the new science of the human past

“Tracing back fifty thousand years in the past, our genome is scattered into more than one hundred thousand ancestral stretches of DNA, greater than the number of people who lived in any population at that time, so we inherit DNA from nearly everyone in our ancestral population who had a substantial number of offspring at times that remote in the past.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past

“the multidimensionality of human traits, the great variation that exists among individuals, and the extent to which hard work and upbringing can compensate for genetic endowment, the only sensible approach is to celebrate every person and every population as an extraordinary realization of our human genius and to give each person every chance to succeed, regardless of the particular average combination of genetic propensities he or she happens to display. For me, the natural response to the”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past

“The avalanche of new data that has become available in the wake of the genome revolution has shown just how wrong the tree metaphor is for summarizing the relationship among modern human populations.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the new science of the human past

“But “ancestry” is not a euphemism, nor is it synonymous with “race.” Instead, the term is born of an urgent need to come up with a precise language to discuss genetic differences among people at a time when scientific developments have finally provided the tools to detect them.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past

“Constant effort to struggle against our demons—against the social and behavioral habits that are built into our biology—is one of the ennobling behaviors of which we humans as a species are capable, and which has been critical to many of our triumphs and achievements”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past

“a result, the most efficient way for evolutionary forces to spread beneficial mutations has often been to invent mutations anew rather than to import them from other populations.44 The limited migration rates between some regions of Africa over the last few thousand years has resulted in what Ralph and Coop have described as a “tessellated” pattern of population structure in Africa. Tessellation is a mathematical term for a landscape of tiles—regions of genetic homogeneity demarcated by sharp boundaries—that is expected to form when the process of homogenization due to gene exchanges among neighbors competes with the process of generating new advantageous variations in each region.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past

“A great surprise that emerges from the genome revolution is that in the relatively recent past, human populations were just as different from each other as they are today, but that the fault lines across populations were almost unrecognizably different from today.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past

“The right way to deal with the inevitable discovery of substantial differences across populations is to realize that their existence should not affect the way we conduct ourselves. As a society we should commit to according everyone equal rights despite the differences that exist among individuals”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past

“So how much Neanderthal ancestry do people outside of Africa carry today? We found that non-African genomes today are around 1.5 to 2.1 percent Neanderthal in origin,24 with the higher numbers in East Asians and the lower numbers in Europeans, despite the fact that Europe was the homeland of the Neanderthals.25 We now know that at least part of the explanation is dilution. Ancient DNA from Europeans who lived before nine thousand years ago shows that pre-farming Europeans had just as much Neanderthal ancestry as East Asians do today.26 The reduction in Neanderthal ancestry in present-day Europeans is due to the fact that they harbor some of their ancestry from a group of people who separated from all other non-Africans prior to the mixture with Neanderthals (the story of this early-splitting group revealed by ancient DNA is told in part II of this book). The spread of farmers with this inheritance diluted the Neanderthal ancestry in Europe, but not in East Asia.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past

“We now know that nearly every group living today is the product of repeated population mixtures that have occurred over thousands and tens of thousands of years. Mixing is in human nature, and no one population is—or could be—“pure.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the new science of the human past

“By computing the proportion of European male and female ancestors that would be necessary to produce the observed difference in European ancestry between chromosome X and the autosomes, Bryc was able to estimate the separate male (38 percent) and female (10 percent) proportion of European ancestors in African Americans.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past

“more plausible explanation is that in this period, it began to be possible for single males to accumulate so much power that they could not only gain access to large numbers of females, but they could also pass on their social prestige to subsequent generations and ensure that their male descendants were similarly successful. This process caused the Y chromosomes these males carried to increase in frequency generation after generation, leaving a genetic scar that speaks volumes about past societies.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past

“Evidence of the antiquity of inequality should motivate us to deal in a more sophisticated way with it today, and to behave a little better in our own time.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past

“A concern is that when members of groups are directly engaged in scientific investigation of their own history, people’s wish that certain things should be true often colors presentation of the findings.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the new science of the human past

“The truth is that India is composed of a large number of small populations.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the new science of the human past

“But the data are sternly consistent: the evidence for Neanderthal interbreeding turns out to be everywhere.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the new science of the human past

“The geneticist Daniel Bradley and his colleagues identified a Y-chromosome type that is present in two to three million people today and derives from an ancestor who lived around fifteen hundred years ago.16 It is especially common in people with the last name O’Donnell, who descend from one of the most powerful royal families of medieval Ireland, the “Descendants of Niall”—referring to Niall of the Nine Hostages, a legendary warlord from the earliest period of medieval Irish history.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past

“In the oldest text of Hinduism, the Rig Veda, the warrior god Indra rides against his impure enemies, or dasa, in a horse-drawn chariot, destroys their fortresses, or pur, and secures land and water for his people, the arya, or Aryans.1”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the new science of the human past

“But on the Y chromosome, the studies found a pattern that was strikingly different. In East Asians, Europeans, Near Easterners, and North Africans, the authors found many Star Clusters with common male ancestors living roughly around five thousand years ago.18 The time around five thousand years ago coincides with the period in Eurasia that the archaeologist Andrew Sherratt called the “Secondary Products Revolution,” in which people began to find many uses for domesticated animals beyond meat production, including employing them to pull carts and plows and to produce dairy products and clothing such as wool.19 This was also around the time of the onset of the Bronze Age, a period of greatly increased human mobility and wealth accumulation, facilitated by the domestication of the horse, the invention of the wheel and wheeled vehicles, and the accumulation of rare metals like copper and tin, which are the ingredients of bronze and had to be imported from hundreds or even thousands of kilometers away.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past

“Today there is an intricate caste system that shapes the lives of many people within Ethiopia, with elaborate rules preventing marriage between groups with different traditional roles.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the New Science of the Human Past

“a perennial debate among historians is the extent to which the human past is shaped by single individuals whose actions leave a disproportionate impact on subsequent generations. Star Cluster analysis provides objective information about the importance of extreme inequalities in power at different points in the past.”
― David Reich, Who We Are and How We Got Here: Ancient DNA and the new science of the human past