Primates are mammals with high cultural significance in ancient societies. The objective of this research is to explore the material culture and biological remains of primates found in Teotihuacan, one of the largest pre-Hispanic urban areas of Mexico. Remains of Mesoamerican spider monkeys (Ateles cf. A. geoffroyi) were found in the Pyramid of the Moon, Xalla, and the Plaza of the Columns. Portable material culture that resembles primates was recovered elsewhere within Teotihuacan, but mostly in Tetitla and La Ventilla. Murals with representations of monkeys were found at these last two Teotihuacan sites. Possibly, primates reached Teotihuacan because of relationships with peoples from more distant lands such as the Mayan region as well as the Oaxacan province ruled by Monte Albán. The rise of the presence of primates in Teotihuacan occurred during the Classic period (~200–550 CE); however, it is relatively scarce considering the large size of the city and the long period of time in which Teotihuacan had been researched. Nevertheless, the existence of monkeys in Teotihuacan, either as exotic animals or as portable objects, does also seem to indicate that they were disseminated within different parts of the city. Thus, living primates and their representations circulated with their symbolic value in Teotihuacan, particularly among members of the ruling elite, and likely among members of other neighboring Mesoamerican societies.

This brief chapter introduces the book. The rationale, scope, and coverage are summarized, including mention of topics that are not covered. Aspects of debate, disagreement, and consensus in the field are summarized before the chapter is concluded with a look to future potential progress.

This chapter explains why I wrote this book and it provides an outline of each chapter. This book traces the history of the scientific discipline that I call narrative phylogenetics from its origin in the second half of the nineteenth century to today. Narrative phylogenetics is a storytelling discipline that is concerned with tracing the evolution of lineages, and it is driven by speculations about the evolutionary process and the evolutionary descent of characters from precursors in hypothetical ancestors. Although phylogenetics has developed enormously since then, narrative phylogenetic reasoning remains visible in the scientific debates of today.

The notion that our planet and its inhabitants have not remained exactly as the Creator was supposed to have made them was in the air long before 1859, when the English natural historian Charles Darwin collected and published his evolutionary ideas in his great work On the Origin of Species by Means of Natural Selection. By that time geologists had long known that the 6,000 years allowed by the Bible since the Creation was vastly inadequate for the sculpting of the current landscape by any natural mechanism; and the biologists who were just beginning to study the history of life via the fossil record were not far behind them. Around the turn of the nineteenth century, the French zoologist Jean-Baptiste Lamarck began to argue that fossil molluscan lineages from the Paris Basin had undergone structural change over time, and that the species concerned were consequently not fixed. Importantly, he implicated adaptation to the environment as the cause of change, although the means he suggested – subsequently infamous as “the inheritance of acquired characteristics” – brought later opprobrium.

Like every one of the many millions of other organisms with which we share our planet, the species Homo sapiens is the product of a long evolutionary history. The first very simple cellular organisms spontaneously arose on Earth close to four billion years ago, and their descendants have since diversified to give us forms as different as streptococci, roses, sponges, anteaters, and ourselves.

While it isn’t necessary to do so, it’s often good to start a book by saying something that is clearly true. So, let’s do that. Science has had (and continues to have) a significant impact upon our lives. This fact is undeniable. Science has revealed to us how different species arise, the causes of our world’s changing climate, many of the microphysical particles that constitute all matter, among many other things. Science has made possible technology that has put computing power that was almost unimaginable a few decades ago literally in the palms of our hands. A common smartphone today has more computing power than the computers that NASA used to put astronauts on the Moon in 1969! There are, of course, many additional ways in which science has solved various problems and penetrated previously mysterious phenomena. A natural question to ask at this point is: why discuss this? While we all (or at least the vast majority of us!) appreciate science and what it has accomplished for modern society, there remain – especially among portions of the general public – confusions about science, how it works and what it aims to achieve. The primary goal of this book is to help address some specific confusions about one key aspect of science: how it explains the world.

Once upon a time it was fair to say that most people knew little of science. After all, scientists spent years learning their job so it’s clearly tough-going and, by and large, the rest of the world could get by knowing nothing of superconductivity or the origins of the universe. But increasingly our daily lives have come to be dominated by science, and part of that revolution has been the ever-expanding reach of television and the Internet as sources of information. It’s as though, unwittingly, we’ve all signed up to the Open University. And, it should be said, when it comes to science this has all been helped by a growing awareness among those in the trade that they have an obligation to let the world know how they while away their days.

Early hominins were not limited to particular sites or localities in a paleontological or archeological sense, but lived and died in complex and dynamic landscapes and ecosystems of which we have partial, incomplete records. The fossil evidence of early hominin paleoenvironments is always limited, sometimes providing brief snapshots of small areas, other times affording very coarse chronological and spatial resolution over large distances. Taphonomic conditions typically vary within any one locality over time, and from one locality to another. And yet, it is these partial and biased records that we use to build an understanding of the forces that have shaped our evolution.

For as long as scientists have been studying biological evolution, there have been critics heckling them from the sidelines. We discuss some historical aspects of this problem, some personal experiences of the author, and we set up the discussions to come.

A revolution has recently taken place in behavioural biology. Its consequences are far-reaching, both for our self-image as humans and for our relationship with animals. Just a few decades ago, behavioural science was guided by two key dogmas: animals cannot think, and no scientific statements can be made about their emotions. Today, the same discipline holds both ideas to be false and posits the very opposite: animals of some species are capable of insight – they can recognise themselves in a mirror and exhibit at least a basic sense of self-awareness – and they have rich emotional lives that seem to be startlingly similar to those of humans. Situations that lead to strong emotional responses in humans, whether positive or negative – for example, when we fall in love or lose a partner – seem to have the same effect on our animal relatives.