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Sex on Earth: A Celebration of Animal Reproduction
Jules Howard

Neanderthal Man: In Search of Lost Genomes

Neanderthal Man: In Search of Lost Genomes - Svante Pääbo Overall Neanderthal Man is a book that appeals to me as a reader and holder of a biology degree. However, it failed to deliver a concise and interesting focus throughout. The author included far too much superfluous information and too little genetic information- the most interesting part in my opinion. There were also far too many trial and error science moments depicted. Yes, this IS science but it does not make an interesting book to read with such repetitive inclusions. I also found the author himself to be quite distracting, the random inclusions of personal information felt out of place and odd. Overall the autobiography aspects were unnecessary and unwarranted. They also so often came out of the blue that it was jarring. One second we are speaking of another genetic test in the laboratory and next he is stating that he slept with this person or spent days naked on a particular beach. Did this add to the story? No. Did it distract? Quite well.

Neanderthal Man definitely covers an interesting topic, however, it is too long winded and infused with personal information to be wholly enjoyable. I did, however, enjoy the following passages:

The most common type of damage that occurs spontaneously in DNA molecules, whether nuclear DNA or mtDNA, is the loss of a chemical component—an amino group—from the cytosine nucleotide (C), turning it into a nucleotide that does not naturally occur in DNA called uracil, abbreviated U. There are enzyme systems in the cells that remove these U’s and replace them with the correct nucleotide, C. The discarded U’s end up as cellular garbage, and from analyses of damaged nucleotides excreted in our urine it has been calculated that about ten thousand C’s per cell morph into U’s each day, only to be removed and then replaced. Loc177

In fact, the genomes in our cells would not remain intact for even an hour if these repair systems were not there to maintain them. Loc184

I'm quite frankly always struck by the fact that humans have not disappeared from this planet, between our own behavior and our bodies we don't stand a chance.

Using the models for how fast different types of mutations occur in mtDNA, we estimated that the mtDNA ancestor common to all humans alive today, the Mitochondrial Eve, lived between 100,000 and 200,000 years ago, as Allan Wilson and his team had found. However, the ancestor that the Neanderthal mtDNA shared with human mtDNAs lived about 500,000 years ago; that is, she was three or four times as ancient as the Mitochondrial Eve from whom all present-day human mtDNAs are descended. Loc325

...we suggested that Neanderthals were probably similar to modern humans in having little genetic variation and that they had therefore expanded from a small population, just like us. Loc1439

There are two species of chimpanzees, both living in Africa. The “common” chimpanzee lives in equatorial forests and savannahs in a patchy distribution stretching from Tanzania in the east to Guinea in the west, while the bonobo, sometimes called the “pygmy chimpanzee,” lives only south of the Congo River, in the Democratic Republic of Congo. Comparisons of DNA sequences had shown that the two chimpanzee species are the closest living relatives of humans, our lineages having split perhaps some 4 million to 7 million years ago. A bit further back, perhaps 7 million to 8 million years ago, humans and chimpanzees shared an ancestor with the other African great ape, the gorilla. Orangutans in Borneo and Sumatra share with the other great apes and humans an ancestor who lived perhaps 12 million to 14 million years ago  ... Loc1678

 I had always thought of myself as gay. In the street, I would certainly mostly notice good-looking guys. But I had also been attracted to women,  especially those who knew what they wanted and could be assertive. I’d had relationships with two women before. Yet, I thought that being together with Linda, who was married to a colleague and had two children, was not a great idea. It could be a temporary thing at most. But over weeks and months it became more and more clear that we understood each other at many levels, also sexually. Nevertheless, when Mark and Linda returned to Penn State University after their year in Munich, I was sure that my relationship with Linda would end. But that was not to be. Loc1579

Again making comparisons between randomly chosen pairs, he found an average of 13.4 differences between any two individuals. It was, to my mind, an amazing observation. Seven billion humans hugely outnumber chimpanzees, perhaps numbering fewer than two hundred thousand. And humans live on almost every speck of land there is on the planet while chimpanzees live only in equatorial Africa. Yet any two chimpanzees carried three to four times as many genetic differences from each other than two random humans. Loc1686

Genetic variation is known to be a marker of a healthy population, which also leads me to wonder how humans continue to exist...at this point it seems mere numbers.

The mammoth sequences were identical to those of the Asian elephant but differed at two positions from the African elephant version, suggesting that mammoths were more closely related to Asian than to African elephants. Loc1825

The giant sloths had left behind large amounts of droppings, which archaeologists dressed up with the fancy name of coprolites. In fact, in some caves in places like Nevada, the entire floor, to some depth, is largely made up of old ground-sloth feces. Loc1881

I need to go to a Nevada cave, stat.

His results suggested that people who are of European or Asian ancestry have inherited between 1 and 4 percent of their DNA from Neanderthals. David and Nick did a different analysis where they essentially asked how far Europeans and Asians are toward being 100 percent Neanderthals. The answer varied between 1.3 and 2.7 percent. Thus we concluded that less than 5 percent of the DNA of people outside Africa came from Neanderthals—a small but clearly discernible proportion. Loc3385

But since we are humans, we are more interested in what makes humans human than in what makes chimpanzees chimpanzee. We should not be ashamed of being “humancentric” in our interests. In fact, there is an objective reason to be so parochial. The reason is that humans, and not chimpanzees, have come to dominate much of the planet and the biosphere. We have done so because of the power of our culture and technology; these have allowed us to increase our numbers vastly, to colonize areas of the planet that otherwise would not have been habitable for us, and to have an impact on and even threaten aspects of the biosphere. Understanding what caused this unique development is one of the most fascinating, perhaps even one of the most pressing, problems that scientists face today. Loc3585

I have to disagree with the author here, there is all the reason to be ashamed.

According to the fossil record, Neanderthals appeared between 300,000 and 400,000 years ago and existed until about 30,000 years ago. Throughout their entire existence their technology did not change much. Loc3593

Amazingly, even crude measures such as the size of the testicles relative to the body reflect this difference in male competition for fertilizations. Whereas chimpanzees have large testicles, and the even more promiscuous but smaller bonobos carry around even more impressive sperm factories, the intimidatingly huge silverback gorillas have puny little testicles. Humans, as measured both by testicle size and evidence for positive selection on genes relevant for male reproduction, seem to be somewhere between the extremes of chimpanzee promiscuity and gorilla monogamy, suggesting that our ancestors may have been not so unlike us, vacillating between emotionally rewarding fidelity to a partner and sexually alluring alternatives. Loc3674