The first two chapters are an account of early human prehistory: the other apes, the various species of Australopithecus and Homo, early toolmaking, and so forth. This includes a brief introduction to systematics. Chapter three continues this with an account of the evolution of the Neanderthals in Europe and our ancestors in Africa, and an overview of their comparative anatomy and morphology.
Two chapters describe the environment in which this happened, presenting a history of the flora, fauna, geology and climate of Spain (and in less detail of Europe) over the last few hundred thousand years. Here Luis Arsuaga brings to life the mountains and forests of Spain, and the cave bears, mammoths, reindeer, and other animals that inhabited them. With bears and hibernation as the link, he goes on to consider the problem of finding enough to eat in this environment, especially in glacial periods. He looks at foraging and hunting (or scavenging) as sources of food, at the development of hunting technology, and at the extinction of many species. A chapter on demographics and life histories then explains how the archaeological record is used to estimate population densities, life expectancies, and so forth for both Neanderthals and Cro-Magnons.
Luis Arsuaga includes just a little bit of abstract philosophy of mind in an overview of debates over consciousness, sentience, language, and their evolutionary origins; he argues that Neanderthals had language and self-awareness, but lacked our more advanced symbolic abilities and vocal anatomy; evidence for "funerals" or other ritual behaviours is not conclusive. And he reconstructs the contact between Neanderthal and Cro-Magnon, with the latter's superior tools and social organisation giving them an edge in the last glaciation, and the last Neanderthals living in southern Spain. A brief final chapter recapitulates the story and glances at what came next, at agriculture and domestication.
Only a few rough graphs and maps are included in The Neanderthal's Necklace: a decent map of Spain is probably the major omission for non-Spanish readers. The publisher of this translation has, rather annoyingly, converted all the units from metric to Imperial, though the subject is surely scientific enough to warrant having left them. And a digression explaining the "grandmother" theory of menopause seems awkwardly "tacked on". Otherwise, there is not much to fault — this is a superb piece of popular science, one that does justice to its fascinating subject.