A Brief History of Everyone Who Ever Lived: The Human Story Retold Through Our Genes

by Adam Rutherford

our genomes are slowly purging themselves of Neanderthal DNA, which suggests that these matings were not to our advantage, but not massively disadvantageous. Our DNA around Neanderthal chunks is undergoing weak negative selection,

The observation that there is less Neanderthal DNA on our Xs implies that the first encounters we had with them that resulted in procreation were male Neanderthals with female Homo sapiens.

Around a million years ago, somewhere in Africa, a group of humans lived who were to be separated into us, the Neanderthals, and the Denisovans.

Pope John Paul II pontificated, as popes do, in 1996 that evolution was more “than just a theory,” which while being a generous bridging gesture between the magisteria of science and religion, misunderstands that theories in science, unlike in the vernacular, are the top of the intellectual pile, the zenith of descriptions of the true nature of nature. Theories are the best we’ve got.

just like with Homo sapiens, the Neanderthals mated with the Denisovans too).

The seven billion of us alive today are, according to all the evidence available to us, the last remaining group of human great apes from a set of at least four that existed 50,000 years ago.

Whenever humans met—sapiens, Neanderthal, Denisovan—they had sex.

We carry the past with us. There was no beginning, and there are no missing links, just the ebb and flow and ebb again of living through epochs. Those ancient people never went extinct—we just merged.

There may have been health benefits for a regular food chain, but this has been disputed as some archaeological remains suggest that people got shorter after domestication, which can be associated with a less nutritious diet.

The “Paleo Diet” is a popular fad that eschews processed foods and carbohydrates in favor of the only foods imagined to be available to the hunter-gatherers of the Paleolithic: no dairy or processed grains, no lentils, beans, peas, or other human-designed veg. Nuts are OK, but no peanuts, as they’re a farmed product. It is almost certainly built on bunkum foundations, as indeed most fad diets are.

The Yamnaya came from the Russian Steppes, driving sheep, riding wagons, making bronze jewelry, and covering their dead in ochre as part of ritual burials. They came and rapidly their way of life spread into middle Europe, bringing their culture and genes, and their fair skin.

The absence of lactase, or its reduced activity, means that the lactose doesn’t get digested in the small intestine, so it passes into the colon, where it encounters bacteria that can break it down and it ferments, causing gas buildup. That’s the direct cause of the bloating and fartiness, but also the increased pressure triggers diarrhea, and so on. This is called lactose intolerance, and admittedly though not particularly pleasant, it’s not the worst condition someone can have, and is pretty normal for most people if they drink milk into adulthood. Which is why most people don’t.

we can say with confidence that the Africans who populated the Middle East and southern Europe 50,000 years ago were dark skinned. We also know from the DNA of burials in Hungary and Spain and the man from Loschbour in Luxembourg that these hunter-gatherers had dark skin around 8,000 years ago. There’s no trace of genetic fair skin between those two dates.

The acres and tons of archaeological evidence for 400 years of the Roman Empire in Britain are rich and wondrous. But the biological traces are comparatively absent.

this supports the idea of a single, small population seeding the continents, and—unlike in Europe or Asia—these people being cut off, with little admixture from new populations for thousands of years, at least until Columbus.

suggest that that the Beringian Standstill hypothesis is correct: All Native Americans, north and south, have versions of genes relating to diet that are suited to their current environments, but born of an ancient population subject to local adaptation in the frozen north, thousands of years ago.

Chang factored that into a further study of common ancestry beyond Europe, and concluded in 2003 that the most recent common ancestor of everyone alive today on Earth lived only around 3,400 years ago.

You are of royal descent, because everyone is. You are of Viking descent, because everyone is. You are of Saracen, Roman, Goth, Hun, Jewish descent, because, well, you get the idea. All Europeans are descended from exactly the same people, and not that long ago. Everyone alive in the tenth century who left descendants is the ancestor of every living European today,

At times you are extroverted, affable, sociable, while at other times you are introverted, wary, reserved.

Some research had shown in 2005 that British Pakistanis, while generating 3.4 percent of the children born in the UK, accounted for 30 percent of the recessive congenital disorders.

Racism is hateful bullying, and a means of reinforcing self-identity at the expense of others: Whatever you are, you’re not one of us.

There are no essential genetic elements for any particular group of people who might be identified as a “race.” As far as genetics is concerned, race does not exist.

book published in 2013 by the former science editor of The New York Times, Nicholas Wade, made a number of questionable assertions relating to the genetics of race. A Troublesome Inheritance posed some ideas that race is not only very clearly defined genetically, but that these distinctions in DNA account for not just the physical characteristics of certain populations, but also some of the social and cultural behaviors. The book frequently misrepresents much of the work that is used to defend his assertion that recent evolution within so-called races explains why certain people appear to be better or worse at certain things. According to Wade, the English display a “willingness to save and delay gratification” and this is absent from certain tribal cultures. Jewish genes are “adapted for success in capitalism.” The Chinese are predisposed to obey authority (how similar this sentiment is to that of Galton expressed in the letter to the Times in the nineteenth century). These statements are unsupportable in any form based on our knowledge of history, genetics, and cognitive ability. They are also clumsy and gross stereotypes and, in my opinion, straightforward racism.

assertions of slavery being effectively a program of selective breeding are merely vaguely racist wish-fulfilment, confirmation bias, or yet another form of adaptationism.

In early versions of the Book of Isaiah, written in Hebrew, there is a prophecy that uses the word almah to describe the mother of a boy named Immanuel, meaning “God is with us.” Almah has no direct translation in English, nor in ancient Greek, but broadly means “young woman,” or “woman who has not yet borne a child.” By the time of Jesus, the Jews had adopted Greek and Aramaic, and no longer spoke Hebrew. Almah became the Greek Parthenos, which has a more specific meaning as “virgin.” It’s the root of a good biological term, parthenogenesis, used to describe the generation of young in some insects and reptiles in the absence of a male: a virgin birth. But in a mutated translation of a single word, the woman becomes a virgin, and the child becomes the Messiah, and the story of Jesus has instantaneously been transformed. Matthew and Luke render it true in the New Testament, a billion Catholics hold this as gospel, and that’s what we all sing in Christmas carols.

We know that height is highly heritable. Dozens of studies over a century have shown that the vast majority of differences in height in a given population are down to genes, and only a small proportion due to the environment.

We are culturally programmed to misunderstand genetics, from the Hapsburg Lip to the way we talk about inheritance. For the most part it matters for science. We should care about learning and understanding things so that they are as up to date as possible, and not beset by myth or misunderstanding.

the Chinese had the highest rates of defective MAOA—77 percent—and white Caucasians the lowest at 34 percent. Do the Chinese have a reputation as being genetic warriors?

People who were conceived during the Hongerwinter are now in their seventies, and many of them had children who are also now adults. It was not startling that so many of the survivors had so many health problems, but the fact that their children did too was a surprise. In mammals, epigenetic modifications tend to get reset each generation, but some, very limited, rare epigenetic tags appear to be passed down from parent to child, at least for a couple of generations.

On the whole, we have as many children as we wish to have, not as many as possible to maximize the chances of our genes surviving the assault of existence and time. In the nineteenth century, women in the UK averaged 5.5 children, but by the end of the First World War it was down to 2.4.

Christians sometimes say that they perpetually doubt their own faith, but it’s a different type of doubt from the scientist’s. Christians appear to doubt under the assumption that their assumptions will be affirmed. Scientists doubt with the explicit plan that their results will be overturned.

We shall not cease from exploration And the end of all our exploring Will be to arrive where we started And know the place for the first time. “Little Gidding,” T. S. Eliot

What a senseless phrase is “curiosity killed the cat.” To be incurious is to be inhuman. We did look inward into the hidden kingdoms of anatomy, then cells, and now genes. We also looked up to the skies, and down into the ground and seas, and into the invisible worlds of the atoms, and subatoms, and now the quantum realm. We are the explorers, and science is exploration.