Chapter 4 brings the student fully into today’s LOAC with details of 1977’s Additional Protocol I and Protocol II. It explains why there was a need to update the 1949 Geneva Conventions and why A.P.s I and II, initially favored by the US, turned out not to be what the US and her allies had anticipated. There were positive changes and additions in both Protocols, as well as regrettable LOAC modifications. Both sides of that coin are examined, with discussion of the lasting results of both the positive and negative changes. It is significant to note that US self-interest did not always prevail, and to explain the basis of that lack of international consensus. Relaxing the requirements for prisoner of war status continues to block US ratification of either Protocol. In the A.P. negotiations the US paid a price for its somewhat ill-advised Vietnam venture but America has, by and large, learned to live with the AP I and II provisions it initially fought. Additional Protocol III (2005), far less significant than the earlier Protocols I and II, is also discussed, if briefly.

There are various calculational methods beyond the perturbation theory of thethat can be applied in specific circumstances to give either exact or approximate results. In this chapter some of the most common methods are explained. We start with the Rayleigh–Ritz variational method that can be used to obtain an upper-bound estimate of the ground-state energy of a quantum-mechanical system. Next we examine multi-electron atoms. In such a case simple application of perturbation theory becomes difficult and more needs to be done.

Chapter 1 provides an overview of the Ice Age in North America. It covers the issues and controversies surrounding the Ice Age peopling of the continent, and introduces the volume chapters and key dating methods with which archaeologists can tell time. It then provides a summary overview of human evolutionary history in order to bring people to Northeast Asia, their jumping-off point for the move into the Americas.

Chapter 8 provides a detailed look at the Clovis complex, the earliest, most widespread occupation in the Americas, exploring Clovis adaptations to a highly varied landscape and one changing rapidly as the Ice Age waned. It focuses on the possible role of Clovis hunters in one of the most perplexing whodunits of science: the extinction of some thirty-eight different genera of Ice Age giant mammals from mammoth and mastodon, to saber-toothed cats.

Chapter 7 turns to the question of how, having made it to the Americas, the first people spread with what appears to be archaeologically breathtaking speed across a continent about which they knew nothing of its climate, resources, or routes. Although highly skilled hunter-gatherers, how did the first people learn to adapt to this utterly unknown land, and do so as successfully as they did?

Chapter 6 seeks to bring together the various threads from previous chapters on glacial geology, archaeology, linguistics, anatomy and genetics to synthesize what we know of who the first peoples were, where they came from and when, and how they travelled to the continent. More broadly, it examines the degree to which there is (or ought to be) convergence among these very different lines of evidence.

Chapter 2 sets the Ice Age (Pleistocene) environmental stage for the peopling of the Americas. It provides a history of glaciation in North America, and the consequences of the Ice Age for the continent’s land, plants and animals, on the routes that may have been used and when by the first peoples. It covers the climate changes over time that would have impacted people and their environment, including the extinction of the Pleistocene megafauna.