The debate about what divides our species from the rest of the natural world is not a new one. In 180AD, the Greco-Roman poet Oppian of Cilicia declared that hunting “the kingly dolphin” was immoral, on the grounds that dolphins were once ­human beings but had exchanged the land for the sea, yet “even now the righteous spirit of men in them preserves human thoughts and human deeds”. The ancient Greeks deemed the killing of a dolphin equal to murder, and punishable by death. In the latter part of the 18th century Jeremy Bentham wrote:

It may one day come to be recognised that the number of the legs, the villosity of the skin, or the termination of the os sacrum, are reasons equally insufficient for abandoning a sensitive being to the same fate . . . The question is not, Can they reason? nor Can they talk? but, Can they suffer?

Charles Darwin observed that the ­mental difference between human beings and other animals is one of degree rather than kind. In November 1870 Thomas Huxley, known as “Darwin’s bulldog”, lectured the Metaphysical Society in Oxford under the title: “Has a Frog a Soul? and if so, of what Nature is that Soul?” And, a generation later, Ludwig Wittgenstein wrote: “If a lion could speak, we could not understand him.”

In our hierarchical world, there are levels of awareness yet to be resolved. As we move through the post-imperial age of the Anthropocene, through what has become known as the Great Acceleration – the relentless sixth mass extinction that scientists and conservationists date to approximately the middle of the 20th century – the questions seem to be ever more urgent. We are faced, in other species, with the mirror of our own depredations.

The other day, almost by accident, I went to the zoo. Turning a corner, I saw what all the fuss was about. A crowd of people was gathered at the window, peering intently, holding up smartphones. Looking over their heads, I couldn’t see anything at first. Then, with a shock, I saw it. Sitting on a ledge, with its back to the wall, at one side of the glass pane: a gorilla.

It was so big I could barely believe it. I couldn’t compute it as a living creature; it looked more animatronic than animate. The largest person could easily sit inside it, and still be overwhelmed by its physical presence. It might even have been a person in a fancy-dress suit. It made me feel breathless. Against what I presumptuously consider to be my better nature, I kept looking at the primate, the prime ape. It was moving gently, and seemed to be muttering to itself. As I peered through the slightly misty, smeary glass, I felt deeply uncomfortable. Actually, I couldn’t look at it at all, for fear that it might look at me, that its gaze might meet mine and that, in its eyes, I might see my own reflection.

Our relationship with animals has been made even more urgent, and yet more remote, by the way they have become part of the 24/7 media cycle. A killer whale named Tilikum languishes in captivity and, in an apparently paranoid state, kills his trainer. A documentary turns the story around; as a result, the whale’s captors find their takings and stock value plummeting. Cecil the lion is shot in Zimbabwe by an American dentist and the outcry rings around the world. A small boy climbs into a Cincinnati gorilla enclosure and Harambe, a 17-year-old silver­back, gets shot. The very fact that these animals have names speaks to the notion that we know almost nothing about them. What they want, what they feel, what they say.

These narratives – the identities we impose on animals – say more about us than they do about the creatures. People speak for primates and cetaceans. Opinion is outraged. Action is demanded. Yet we have never been further from the natural world. Most of us experience it only vicariously, through such news stories, or in lovingly crafted documentaries that leave us stunned by the beauty of other species but utterly helpless, apparently, to save them from a destruction that we have set in train. There was never a better time to ask: what do animals really think of us?

To the Belgian philosopher, photographer and artist Chris Herzfeld, it is clear. In her book Wattana: an Orang-utan in Paris, she draws on one ape’s story to stand up, shakily, balancing on the back of its bipedal legs, for all the others. In wonderfully concise and restrained prose (translated from the original French by Oliver Y and Robert D Martin), Herzfeld lays out the evidence for primate culture. Her particular area of study is that of apes in human captivity, a shared history of species which has a three-centuries-old history in the menagerie of the Jardin des Plantes in Paris. Here, and in hundreds of other zoos around the world, the boundaries between Homo sapiens and their nearest genetic neighbours are blurred.

Imprisoned non-human primates are “denatured”, she says: “false apes as opposed to natural apes”. Assimilated into our society, they have become unclassifiable and therefore problematic (hence the furore about the boy in the gorilla enclosure). From entertaining old French nobility – who would often be wearing their own fancy dress – to tracing their leathery, agile fingers over the touchscreen of an i-Pad, they “show a considerable good will in collaborating with humans”. Yet in adopting our characteristics (not least in popular culture, from the PG Tips chimps to Planet of the Apes), primates only underline the “fundamental trait of hominoids: ­plasticity”, an almost pathetic adaptability.

Wattana and her conspecifics can tie knots, using dexterous digits and even their mouths, in an almost abstract expression of art and craft. They decorate their captive spaces in simulacra of their wild nests; Herzfeld notes that in their native forests primates spend up to half their lives in such cosy shelters. She makes a telling point in noting how we give an anthropocentric account of their stories, observing that our natural history of apes focuses on their ability, or not, to use tools, disregarding their craft of such nests. This is an implicitly gendered bias, she hints. Biologists and other scientists, often men, rely on the “omnipresence of the tool”, a hard function, as opposed to the soft function of (home)making, of weaving, of fabrics. (Elaine Morgan, who revived the alternative evolutionary theory of the “aquatic ape”, faced a hostile reception to her ideas in the 1980s.)

Anthropomorphy may be a besetting sin for science; yet it also downgrades the experience and knowledge of the human keepers of captive animals. Their attachment to their charges is the “love that correctly reveals the kinship”, as Herzfeld puts it. If apes produce artefacts, then surely the most astounding notion in her book is that of an intrinsic aesthetic sensibility among primates. Chimpanzees are adept at creating art, painting and drawing if given the materials. They will compose and make marks, and consider their artwork with a degree of concentration that seems to indicate artistic expression.

Nor do they need the tools and media we supply. In Sri Lanka, elephants have been seen to draw in the sand with their trunks. For Herzfeld, this is an example of Funktionslust in other animals, “a pleasure in doing what they know they do well”. But is it art, too: a blackbird singing, long after the urge to reproduce has been satisfied; a raven exulting in its aerial acrobatics; a dog “excited by the tumult of the waves”; a bower bird painting its twig-and-leaf-litter constructions with sticks daubed in berry juice?

It is arrogance on our part to argue that these are mere mechanics. Darwin – who was disconcerted by the extravagance of peacocks – believed that birds have “a taste for the beautiful”. A scene in Wattana haunts with its potent poetry: that of Chantek the orang-utan, taught to communicate in sign language by the anthropologist Lyn Miles and taken out for an evening walk in the Tennessee hills. Chantek points up at the moon and asks, “What is that?”

Frans de Waal has been working with apes for forty years. As an ethologist, he too is keen to address animal cognition. In his book Are We Smart Enough to Know How Smart Animals Are?, he turns the ­argument neatly on its head. He not only disregards the doctrinaire scientific scepticism about anthropomorphy but positively celebrates it, describing the isolationist attitudes of ­animal behavourists and their studies of “non-humans” as “anthrodenial”. (De Waal is inordinately fond of arcane terms – my favourite being “theriomorphic”, indicating the state of transformation from human to animal.) He makes clear that what was once regarded as the crucial potential in our relationship with other species – that they may possess the ability to use language,

like us – is really not the point. Unlike the hopes of 1960s renegade scientists such as John Cunningham Lilly, who believed we might one day speak to captive cetaceans in “dolphinese”, De Waal’s accent is on more important assets that we share: culture, empathy, morality, even politics.

He draws these conclusions from his first-hand experience with primates. “I regularly have this eerie impression that apes look right through me,” he writes, “perhaps because they are not distracted by language.” His recurrent trope is the notion that we are set apart from other species. He reasons that this denies the process of evolution which led to us, and is frustrated by the argument that “human evolution stopped at the head”: that our brains are so far in advance of the rest of the animal world that we represent a step change in development which can never be breached or rivalled.

Previous experiments in animal cognition have been tainted by this approach. Primates are said to do less well in tests than children; yet when the latter are in the laboratory, they are accompanied by parents or carers, who inevitably give their charges unconscious clues that allow them to respond to the task in hand. Chimpanzees – which respond equally well to emotion and social stimulation – are left alone, without reassurance, and consequently do less well. We dismiss their wondrous ability to imitate us as “aping”, a pejorative term that would be better seen for what it is: an acute awareness of our otherness, and, perhaps, their own attempt to bridge that gap. De Waal draws on his own experience and a vast array of scientific papers to support his ideas. His book is rich and digressive, if occasionally repetitious and circuitous. It is certainly a significant contribution to the debate.

Carl Safina is a more obviously empathetic guide. In Beyond Words, he takes us out of the laboratory and the zoo and into the wider, wilder world. We encounter elephants in Kenya which are able to sense the distress of fellow elephants that are being culled hundreds of miles away. Much of what they are “saying” to each other is below the frequencies we can hear. Their calls seem to be transmitted through the land, the very soil; pachyderms have a sense organ in their feet which allow them to “hear” others of their species. In this sense, they feel the Earth of which they are – or were – an integral part; as if their monumentality were an echo of their abiding but dwindling place on a vast continent. Safina stitches together

human and natural history in a telling, salutary manner. He equates the slaughter of elephants with the terrible trade in human beings: the ships that bore slaves out of Africa were laden with ivory, too. The same trade is still going on, in the same place: elephants killed for their tusks, human beings exploited for their misery – refugees, all. “And,” as Safina argues, “because of human expansion, no refuge is safe long-term.”

He seeks to write around this world – a world of wolves intimately linked by family and association, and one of orca (killer) whales, whose social units are so tightly bound and expressed that for the duration of their lives males will never leave their mother. Safina ends up on the north-west Pacific coast, where he makes his most ­direct plea for interspecies understanding as he watches pods of orcas surf through the waters. Twenty-five million years ago, he notes, they were “in possession of our solar system’s brightest brain. In many ways it would be nice if they still were.” Only people create problems, he concludes. Orcas have never been observed to use any violence on their own species.

Elsewhere, scientists such as Hal Whitehead and Luke Rendell – whose groundbreaking book The Cultural Lives of Whales and Dolphins was published in 2015 – suggest that it is because these animals live in such large social groups that they have developed a high degree of emotional maturity: a kind of morality, in order to regulate and codify interactions. Others note that dolphins have highly developed amygdalae, the parts of the brain which process emotion. The American philosopher Thomas I White has even suggested that dolphins may be more emotionally mature than human beings. (Insert your own quip here.)

But it is easy to slip into post-human utopianism. I know many people who would prefer to share their lives with animals rather than with their own species. Some even try to become wild animals in their own right. The question remains: what keeps us apart, and will it end up being the death of us both? You won’t find an answer in any of these three books. But you will find some vital questions. Animals “are not brethren, they are not underlings”, as the naturalist Henry Beston wrote from his Cape Cod shack in the 1920s. He saw them as “gifted with extensions of the senses we have lost or never attained, living by voices we shall never hear . . . other nations, caught with ourselves in the net of life and time, fellow prisoners of the splendour and travail of the Earth”. Animals are our other, our fellow-travellers. For that reason, if for no other, we would do well to listen to them, even if we don’t want to hear what they say.

Philip Hoare’s “The Sea Inside” is published by Fourth Estate

Beyond Words: What Animals Think and Feel by Carl Safina is published by Henry Holt & Co (461pp, $32)

Are We Smart Enough to Know How Smart Animals Are? by Frans de Waal is published by Granta Books (336pp, £14.99)

Wattana: an Orang-utan in Paris by Chris Herzfeld is published by University of Chicago Press (192pp, $26)