What Are Dogs Like?

This book is about the behavior of animals, and in particular about how dogs and other canids (like wolves and coyotes) "make a living" — what a biological organism like the dog actually does, and how and why it does what it does. We want to understand the forces and mechanisms that enable a dog to "tick" as it moves and acts in the world: why Border collies chase after sheep but livestock-guarding dogs don't; why greyhounds make good racing dogs but dachshunds do not; why a newborn pup behaves differently from an adult dog.

For us as ethologists — scientists who systematically investigate the biological bases of behavior — the notion of an animal "ticking" away, something like a clockwork machine, isn't just a clever metaphor. A machine is a device that does work by converting energy into action. Like any machine, a dog's behavior results from the translation of energy into patterns of movement (and ultimately, in the case of biological organisms, into offspring). How it is built, the shape and organization of its parts, and how it acquires the energy it needs to work all determine what a machine will do and set limits on what it can do. In this book, we will ask you to think about dogs and other animals in something of the same way.

You may well immediately and fiercely object that a dog isn't just some kind of mechanical wind-up toy. Surely, plenty of us believe, dogs have personalities and desires that we would never ascribe to a machine. Indeed, it is probably true that dogs and other animals do have "minds" that are at least something like our own. This is an exciting perspective; it is much in vogue in the popular media and it's the focus of a great deal of research in a new field that has come to be known as cognitive ethology. We'll look more closely at some of this work in a later chapter — but we will not often appeal to cognitive explanations in this book. Our aim is to see how much we can understand about why and how animals behave from the standpoint of "traditional" ethology: by considering how the bodies of organisms are constructed and how the shape of that biological machinery determines the patterns of movement and activity that are so important in their lives.

Since the Darwinian revolution, virtually all biologists — and most thoughtful people — have understood that all life on earth is related in an evolutionary web stretching over billions of years. The myriad properties of "biological machines"— the cells, tissues, and body parts and the processes that wire them together — are the result of evolutionary forces that have shaped and reshaped the genetic mechanisms that ultimately are responsible for translating energy into purposeful activity. Darwin's great idea was that evolution — by means of natural selection favoring beneficial variations in form — results in adaptations that enable an animal to acquire energy by eating, to avoid hazards (like being eaten by others), and to reproduce themselves. The central insight of ethology is that an animal's behavior, just like the organic parts that make up the physical form of a biological machine, is itself an adaptive product of those evolutionary forces.

If animals are indeed like machines in some sense, however, it goes without saying that they aren't just simple mechanical devices. Brains, for instance, are surely a critical component of the biological machinery that leads to behavior in higher organisms like dogs (and us) — and the vertebrate brain is quite possibly one of the most complex objects on earth, if not in the entire universe. There are some four hundred billion stars in the Milky Way galaxy — and sixty trillion neural connections in a human brain. The brain of a dog is not quite so cosmically large, but it is nonetheless a formidably complex organ — and it is only one part of an intricately integrated biological machine. Without bones and guts, skin and musculature, eyes and ears, and other organ systems — all products of the animal's genes, honed by evolution — an animal like a dog can't adaptively convert energy into effective action. So behavior must be a consequence of the animal's whole shape, the complex totality of interacting mechanisms that are constructed by its genes.

That said, the notion that animals are just (something like) simple machines does have a long intellectual history. A few centuries ago, the philosopher René Descartes famously articulated the doctrine of dualism, arguing that "body" and "mind" are two different kinds of thing, neither reducible to the other. He saw human beings as possessing both properties. But nonhuman animals, Descartes insisted, were essentially just like cleverly constructed clockwork devices that possess only mechanical bodies and no "soul-stuff." We are not going to take on this ages-old and still-ongoing philosophical debate about the relationship between body and mind. But it is instructive to think about why Descartes was able to view animals through the metaphorical lens of a ticking machine like the works of a clock — and how that idea might help us in understanding behavior.

Clocks are machines that mark out time. Inventive humans have come up with a wonderful range of ways to do this. Sundials indicate the passage of time by a shadow that relates to the position of the sun in the sky. Candle clocks, water clocks, and hourglasses can do the job because they use up various materials at a predictable rate. The mechanical clocks that appeared in the Middle Ages, and were much refined by Descartes's time, worked on a different principle. These devices transferred mechanical movement — the swinging of a pendulum or the deformation of a spring controlling an oscillating wheel — to moving gears. Moreover, early clockmakers and other tinkerers soon discovered that their intricate mechanisms could do much more than just tell time — they could also cause other complex movements of many sorts. Eighteenth-century inventors thus delighted in building remarkable automata, clockwork machines that were intended to be realistic models of people and animals that could simulate lovers kissing, soldiers firing guns, or dogs chasing their own tails. Constructed only with gears that turned other gears, wires that pulled pieces into place, and pendulums that swung them away again, their machines could be made to appear to act in eerily but wonderfully recognizable ways. The tradition — now enhanced by sophisticated digital computational devices — continues today with the animatronic robots you'll find at theme parks around the world. Over the centuries, countless audiences have marveled at these amazing self-operating machines: "How lifelike they are!" Some of these robots can be hard to distinguish, at least at first glance, from the real thing. But the fact is that even a very simple mechanical wind-up toy may have something of the...