HUMANKIND

HUMANKIND is Alexander Harcourt's innovative and illuminating look at how the evolution of the human species has been shaped by the world around us, from anatomy and physiology, to cultural diversity and population density.

Where did the human species originate, why are tropical peoples much more diverse than those at polar latitudes, and why can only Japanese peoples digest seaweed? In HUMANKIND, U. C. Davis professor Alexander Harcourt answers these questions and more, as he explains how the expansion of the human species around the globe and our interaction with our environment explains much about why humans differ from one region of the world to another, not only biologically, but culturally. What effects have other species had on the distribution of humans around the world, and we, in turn, on their distribution? And how have human populations affected each other’s geography, even existence? For the first time in a single book, Alexander Harcourt brings these topics together to help us understand why we are, what we are, where we are. It turns out that when one looks at humanity's expansion around the world, and in the biological explanations for our geographic diversity, we humans are often just another primate, just another species. Humanity's distribution around the world and the type of organism we are today has been shaped by the same biogeographical forces that shape other species. Check out these amazing tidbits — the book is full of them: • Extreme locations, namely island environments and polar environments affect height and metabolism of both humans and animals. • Island inhabitants will be smaller, shorter, and have a lower metabolism in order to conserve food and energy if necessary (being “trapped" on an island as they are). • Polar residents are much larger in order to retain heat. Bigger bodies mean more heat retention, and more room to store food. • Skin color is also a factor on location. Extreme exposure to sun destroys vitamin B9 (folic acid), which is necessary for humans to produce a viable fetus. So 50,000 years ago, when humans were outside all the time, dark skin evolved to protect humans from this. • Conversely, at colder climates that don't get as much sun, pale skin lets in the sun (and also encourages Vitamin D production), as otherwise a calcium deficiency would cause Rickets. Darker-skinned immigrants to northern climes still suffer from Rickets this unless they increase their vitamin D intake. • Indigenous diets have resulted in biological manifestations like the inability to digest milk for most people outside of western european ancestry, or only ethnically Japanese people being able to digest seaweed. • Interestingly enough, up until a few decades ago, milk was a staple for food/famine relief programs in Africa, but as most people couldn't digest the milk, it was actually making the problem worse/making them sicker! The "long view" Harcourt takes in HUMANKIND—50,000 years' worth—about our human evolution and various population bottlenecks in our prehistory (the first movement to North American across the Bearing Straight, for example, or in to Australia, during the last ice age) is fascinating, as the effects of these genetic bottlenecks still show today. Alexander Harcourt is Professor Emeritus in the Anthropology Department at the University of California, Davis. He is the coauthor of Gorilla Society and Human Biogeography and coeditor of Coalitions and Alliances in Humans and Other Animals.