"Almost Like a Whale?" is an interlude between chapters thirteen and fourteen of Darwin's Ghost by Steve Jones, which is itself entitled Almost Like A Whale in its original British edition. Chapter fourteen of the book is merely a reprint of the fourteenth chapter of On the Origin of Species by Means of Natural Selection, "Recapitulation and Conclusion," so this is the last original chapter of Darwin's Ghost.
In "Almost Like a Whale?," Jones looks at human evolution, a topic that Darwin mentions only in passing in The Origin. ("Light will be thrown on the origin of man and his history," Darwin wrote in his last chapter.) Jones notes that "[i]n 1859 not a single human fossil was known, but now thousands have been found." Through genetics, we are now able to examine the degrees to which humans are related to each other and to other species, and examine the longstanding notion that humans are somehow completely different from other mammals.
It turns out to be an interesting examination. Most diversity among humans occurs between individuals, not between groups, meaning that two people living in the same place are more different from each other than the average person in that place is from the average person in another, distant place. The amount of diversity between populations, though, is also fascinating. "The center of variety is in Africa," Jones writes. "Within Africa live peoples as distinct as the Zairean pygmies and the tall Nilotics. Europe, in contrast, can do no better than Greeks and Swedes." The center of variety of a species tends to be the original source of that species, and humanity does seem to have spread from Africa.
Jones also compares humans to other species, noting that chimpanzees have two species (the common and the bonobo) and so do gorillas (the mountain and the lowland), but humans and aardvarks are the only mammals to exist as the only species of their genus. Jones writes that other mammals (with the lone exception of the aardvark) have evolved into many species because they have had time to do so; humanity is recent and has not.
Later in his chapter, Jones notes that humans share 98.8 percent of their DNA with chimps, enough that a "cross between the two primates might at least be possible." Such a hybrid, he adds, would certainly itself be sterile, though, as "two chimpanzee chromosomes are fused and three more are reshuffled."
Jones ends his interlude by coming back to the idea of difference between humans and the rest of nature, writing, "Man, the highest of animals, and the most exalted object which we are capable of conceiving, emerged from the war of nature, from famine and death, as much as did all others. Humans, alone, have gone further." He seems to think that this is true in two ways: first, humanity has to a large extent removed itself from the struggle for existence, as fewer and fewer people die young, and second, Jones believes that "[t]he birth of Adam, whether real or metaphorical, marked the insertion into an animal body of a post-biological soul that leaves no fossils and needs no genes.… However, the new insight that biology gives into our history releases us from the narcissism of a creature that is one of a kind. It shows that humans are part of creation, because we evolved."
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