We humans like to think of ourselves as an exceptional species, towering above the rest of the animal kingdom with almost celestial powers of divinity. At a primordial level, however, we are merely matter. Technically, that makes us animals. This is the message BBC radio host and popular science writer Adam Rutherford relays to the reader in the opening pages of The Book of Humans: The Story of How We Became Us.

Rutherford’s tome subtly meanders its way around two key questions: if we are, in fact, animals, why do we act like gods? And what exactly is it that puts us on a pedestal above our evolutionary cousins? To answer both these questions with the thoughtful insight and measured reasoning they deserve, Rutherford takes us on an intriguing journey through the origins of life, deconstructing our species’ most primal drives and intricate behavioural patterns as he goes. This includes things like sexual mores, tribal social norms, a propensity for love and violence, and the impulsive need to create art to find meaning from life.

But where exactly do the commonalities between humans and animals lie? Well, animals, just like us, Rutherford points out, can communicate; they make tools, and they have sex for pleasure too. The first person to write about this with conviction was Rutherford’s intellectual hero Charles Darwin. Rutherford continually looks to the father of evolutionary biology for intellectual and scientific sustenance, notably referencing two of his most seminal texts.

In his book On the Origin of Species (1859), Darwin only hinted at the idea that placed us on the same tree of life as every other organism. But in The Descent of Man (1871), he clearly defined us as evolved organisms, also recognising that we have what he called “god-like intellect”, whilst “man still bears in his bodily frame the indelible stamp of his lowly origin.” Moreover, much of the evidence accumulated by the scientific community post Darwin has reinforced that thesis, but with much more exactitude and clarity this time around. That is primarily because our knowledge in recent years of how DNA translates into life has been radically transformed.

Rutherford’s greatest asset is his ability to take complex ideas and transform them into an easily digestible narrative for a lay reader brimming with scientific curiosity. Want to understand the basic principle of DNA? Easy, Rutherford explains: try thinking of it as a logbook of every successful reproductive encounter your ancestors ever had. The benefits of such knowledge are enormous, he stresses. Not only does it map out a history of us as individuals, as families, and as a species, but it also gives us a greater understanding of almost all life on Earth. To truly comprehend the basic mechanisms of evolution, Rutherford points to the timescales involved, something he described in his book A Brief History of Everyone Who Ever Lived: The Stories in Our Genes.

It’s now almost universally believed that humankind’s migration story began approximately 80,000 years ago in Africa, an event that subsequently saw our species literally walking out of the continent and spreading across the four corners of the Earth. However, the rate of migration was painstakingly slow: approximately two miles per century.

Not long after this seismic event, another transformation took place. This was the “Great Leap Forward”, occurring 40,000 years ago when we jumped into a state of intellectual sophistication and cultural activity: painting, writing, telling stories, making music – essentially, engaging in a plethora of high-minded ideals.

This brings us on to what is perhaps the most significant theme of Rutherford’s book: how biological and cultural evolution are intrinsically interdependent. An example, Rutherford points out, is having hands to make sophisticated tools. Clearly, our biological framework does most of the heavy lifting. However, we also need brains that control that mode to function correctly. Biology and culture thus consistently complement each other, in an arena where complex sophisticated memes and evolutionary primal drives constantly overlap.

Rutherford, however, sees this as something of a blessing and a curse. On the one hand, it propelled us forward to create art, to reflect on the nature of existence and our own mortality; but, equally, it has enabled us to murder and to maim in significant numbers. As Rutherford puts it rather bluntly, “violence is inherent to nature.”

And when it comes to expressions of violence, humans excel like no other species.

Through our evolved brains, culture, and tool use, we have turned the application of violence into a fine art. “At some point in our history intraspecific violence escalated in scale,” Rutherford writes, noting too how the oldest evidence of group-level violence lies in Kenya 10,000 years ago.

While we do share a number of traits with other mammals, Rutherford believes we should be cautious when attempting to apply human value judgements to their sexual indulgences. He observes, for instance, the common practice of male dolphins kidnapping female dolphins for gang rape. To humans this may seem like a torturous and criminal activity. But it is, Rutherford makes clear, a systematic evolutionary strategy: one that keeps the reproductive chain plodding along at a consistent rate. Or, as he puts it more succinctly, “Evolution is cleverer than you, and in this case much more devious.”

Elsewhere, Rutherford touches upon a whole host of subjects: dissecting the power of language; explaining how homosexuality is common practice across the animal world; and observing that masturbation – practised by both animals and humans – is probably carried out for the simple fact that it feels good.

As a committed Darwinian empiricist, Rutherford believes that most things can be explained using science as a trial-and-error tool. However, he concedes that there are some things it has left us in the dark about, for now at least, such as the origins of language and the evolutionary function of the conscious mind.

And, even though we have evolved differently from our animal counterparts, breaking free from the arduous evolutionary path we both arose from is not as simple or clear-cut as it might appear. The Book of Humans is a fascinating, informative, lucid and thoroughly engaging read, helping us to understand and, ultimately, to accept this great paradox of the human condition.

J.P. O’Malley is a freelance writer.