One day last summer, my Ameraucana hen Dolley picked up a strange green-and-yellow caterpillar. She quickly dropped it and made a series of clicking noises unlike anything I’ve ever heard from a chicken. Then she picked up the caterpillar, walked over to another hen, dropped it on the ground between them, made the same weird noises and picked it up again. She continued in this fashion until she had introduced the caterpillar to every member of the flock. Then she ate it.

What just happened? I’d clearly witnessed some sort of animal communication. But had Dolley made a deliberate decision to talk to the other chickens about the caterpillar? Or was she on autopilot, carrying out a programmed series of behaviors embedded deep in her dinosaur brain, the result of millions of years of natural selection?

Con Slobodchikoff, professor emeritus of biology at Northern Arizona University, has devoted his career to the study of animal language, and he chronicles his findings in “Chasing Doctor Dolittle.” His own work on prairie dogs takes center stage, as it should: In a fascinating series of experiments, Slobodchikoff and his team analyzed the warning calls made by prairie dogs in a colony they studied. The animals clearly had a vocabulary to describe color, size and shape. The scientist learned that the calls were so specific that they could describe a tall person wearing a yellow shirt and a short person wearing a blue shirt. The prairie dogs were also able to make different warning calls for different sizes and shapes of dogs approaching the colony, and to describe how quickly or slowly the dogs were moving. And they could put together labels for new objects they’d never seen before, such as wooden cutouts in strange shapes.

Before Slobodchikoff conducted these experiments, no one knew that prairie dogs were capable of doing anything more than making a sound when predators approached. Technological advances helped make his research possible: It is now much easier to make digital recordings of animal calls, slow them down or speed them up, and analyze their content on a computer. But what really sets Slobodchikoff’s work apart is his willingness to consider the possibility that animals employ a fairly sophisticated vocabulary and don’t just make programmed noises in response to stimuli.

This idea goes against the scientific consensus about animal language. Most scientists, Slobodchikoff explains, are unwilling to “attribute any conscious intent” to animal vocalizations. Animals are not aware of their own existence in the way that we are, the thinking goes, so they cannot be aware of anyone else’s existence, and they cannot make a conscious decision to express their desires and experiences through language. Most of us have abundant evidence to the contrary in the form of our pets, which, he argues, “are plenty aware of themselves and their needs and spend much of their time trying to communicate those needs and desires to their owners.”

‘Chasing Doctor Dolittle: Learning the Language of Animals’ by Con Slobodchikoff (St. Martin's)

“Chasing Doctor Dolittle” makes sense of the emerging field of animal linguistics. Some of these creatures possess not only vocabulary but a rudimentary form of grammar as well. Prairie dogs make one kind of call when a woman wearing a yellow shirt walks through the colony and another kind when she walks through with a bag of sunflower seeds. The second call contains a subject and an object: “Human wearing yellow” is the subject, and what she carries, “sunflower seeds,” is the object.

Bats, whales and even lizards, honeybees and squid make appearances in the book. Analysis of their vocalizations demonstrates that they have some sort of vocabulary, but in many cases we have no idea what they’re saying. The male blue-throated hummingbird, for example, sings a song composed of five different units, and those units are combined in very specific ways that suggest grammar or syntax. But don’t expect a hummingbird-to-English dictionary anytime soon: The painstaking work that Slobodchikoff has done with his prairie dogs has not been replicated across very many species.

This makes the book a bit frustrating for non-scientists. Most of us, through our experiences with animals, already assume that they express their desires and opinions through language. I’ve never met a pet owner who, upon hearing her dog bark or her cat meow, claims to have no idea what the animal is saying. Most of us jump right up and exclaim, “Oh, I forgot your treat!” or “I know, you hate the sound of that vacuum cleaner.” Call it non-scientific, call it anthropomorphizing, but the fact is that most readers won’t be particularly surprised to learn that animals communicate. We’d like to know exactly what they are saying — but for many species, the science just hasn’t progressed that far. Slobodchikoff does a terrific job of explaining how the vocalizations of animals have been analyzed, but most of these stories conclude, as they must, with a statement like: “But unlike [with] our vocalizations, we lack the key that would allow us to decode what the bats are really saying.” Well, yes.

I wish the book had been organized differently: Two early chapters on language theory were clear enough but unnecessary to a general reader, who might rather get on with the animal stories and pick up the scientific concepts along the way. And Slobodchikoff’s prose becomes dull at times, particularly when he gets off the subject of animals and onto humans. One anecdote comparing human to animal behavior begins, “My wife loves to cook exotic dishes that have a variety of flavors.” Slobodchikoff’s language is straightforward; it just isn’t dazzling. And isn’t that what really distinguishes us from the animals?

Amy Stewart is the author of the forthcoming “The Drunken Botanist: The Plants That Create the World’s Great Drinks.”

CHASING DOCTOR DOLITTLE

By Con Slobodchikoff

St. Martins. 308 pp. $25.99