In a cave at the dawn of time, a mother buries her child. She lays a pair of antlers in the tomb and says goodbye. Ever since the accident, she has done all she can to comfort her child. But now, her loved one is at rest.

Qafzeh 11 lived 100,000 years ago in modern-day Israel. Scientists found the child's body in 1971, but recent bone scans hint at an extraordinary backstory. The child suffered a severe brain injury and must have been looked after for several years until being carefully and deliberately buried.

Why is this significant? Early humans were nomadic hunter-gatherers and this child was another mouth to feed. Other animals abandon or even eat their children. This is evidence of prehistoric social care and maternal love for a helpless child.

Around 65,000 years ago, humans began to make complex tools, pottery, musical instruments and cave art. This "great leap forward" led eventually to farming, settlements and the birth of civilisation.

What is behind this success? Maybe Qafzeh 11's story offers a clue. Could humanity's secret weapon be the loving devotion of parents to their children?

Science writer Chip Walter thinks so. In his book Last Ape Standing, he argues hominins "invented childhood". Two developments - bigger brains and bipedalism - led babies to be born "early". So human infants depend on their parents for much longer than any other animal.

"Caring helps us cooperate and cooperation helps us compete," says evolutionary biologist Nicholas Longrich. Unlike most mammals, parents form long-term bonds to raise children. And to help them, they use extensive social networks, from grandparents and nurseries to schools and the welfare stateA safety net put in place by the government to ensure that no-one falls into poverty..

So civilisation is founded on maternal love? Not exactly, says primatologist Dario Maestripieri. He argues we share a lot in common with another successful primate, the rhesus macaque. Monkeys and humans are expert liars and manipulators, manoeuvring themselves to the top of social hierarchies.

"Our Machiavellian intelligence is not something we can be proud of," says Maestripieri, "but it may be the secret of our success." It helped develop bigger brains which we also use to understand the world, invent tools and create art.

Qafzeh 11 was one of the first modern humans to live outside Africa. But at the time, there were six different human species, including the NeanderthalsAn extinct hominid species that lived alongside Homo sapiens until around 40,000 years ago. Their ancestry began in Africa, like ours, but neanderthals migrated to Europe and Asia long before humans. They looked like us but were shorter and stockier with angled cheekbones, prominent brows and wide noses. . Scientists used to think our ancestors quickly wiped out Neanderthals when they arrived in Europe. But evidence now suggests thousands of years of coexistence and interbreeding.

"Neanderthals were different from Homo sapiensThe species to which all modern humans belong. Homo sapiens means "wise man" in Latin. ," says Nicholas Longrich, "but enough like us that we could love them, and they, us". Non-African modern humans have up to 4% Neanderthal DNA, so "a love story worthy of Jane Austen is literally written into our species' DNA."

In a world at war facing the challenge of climate change, nothing could be more important than this: are we fundamentally a species of cooperation or conflict, love or hate?

Yes: Many animals use tools, communicate and solve problems, but only humans teach. This is because we are born entirely dependent on our parents. Without their love and guidance, we cannot survive.

No: We are not the only species to show love for our offspring. All mammals are born defenceless, literally toothless and depend on their mother's milk for survival.

Or... Love is a mixed blessing. The bond between parent and child holds families together. But they also make us overly protective, inward-looking and suspicious of strangers and outsiders.