Along Lake Eyasi in northern Tanzania I come across the Hadza community sitting in male- and female-only groups, with the men playing small lute-like stringed instruments and applying a pre-hunt poisonous tree resin to their metal arrowheads. They light a small fire by rapidly twisting a hardwood twig into a softwood stick from the local Commiphora tree. It soon smoulders and, intrigued, I have a go too. It's surprisingly difficult, but with their help, I get it to smoke eventually.

I've travelled four hours west from the city of Arusha to meet this ancient tribe of hunter-gatherers, and join them in a bow-and-arrow hunt for prey among the thorn bushes. The Hadza people may have nothing – no animals, land or possessions aside from the clothes on their backs – but they are rich in the skills and resourcefulness they need to produce everything from their environment.

That’s not all that sets them apart from most societies. The Hadza are thought to be the most ancient modern humans, the first surviving peoples to have split off from our ancestral family tree, and are not closely related genetically to any other peoples. Their language – a clicking tongue, also called Hadza – is unique and unrelated even to other clicking languages. Some linguists believe Hadza may be close to humankind's first ancestral language.

Dying out

However the language may not be around for long. The Hadza bushmen, who live in groups of around 15 people, are believed to have been living in this remote area for at least 10,000 years, but there are now less than 1,000 Hadza left. Fewer than 400 of them continue to live a stone-age lifestyle – they are among the last hunter-gatherers in a continent of farmers and pastoralists. The numbers will continue to drop, as their land is swallowed up by farmers, government-designated conservation areas and private game reserves. And their sing-song tongue, punctuated with clicks and glottal stops, and which has no words for numbers past four, is no longer being learned by all Hadza children. As the modern world encroaches, the language is in danger of being lost as Hadza make greater use of the widely spoken Swahili tongue.

What is at risk is not simply the vocabulary and grammar of this unique language, but the Hadza's – and by extension, part of humanity's – cultural heritage and expression.

The Hadza are not alone in facing the loss of their native tongue. Every 14 days a language dies. Over half of the approximately 7,000 languages spoken on the planet may disappear by the end of the century. In the age of the Anthropocene, language extinction is happening faster than species extinction. Eighty percent of the endangered languages are African, including Hadza, and the majority have no written form. Once the last speaker dies, so does the language. And for an oral culture, preserving language becomes even more important for maintaining the identity and heritage of a community.

It is said that with every language you speak you gain a new soul. But 80% of the world's population now speak just 1.1% of its languages, and universal languages, like English, dominate the internet, signage and the majority of published texts. So, is the Anthropocene becoming a duller place, in which the rich diversity of humanity's full and wonderful language abilities is reduced to a handful of tongues: English, Mandarin, and a few others? Are we in danger of losing our soul?

Not if some people have their way. They are fighting back to preserve rarer tongues - in some cases, with great success.

Unlikely saviour

Perhaps the most successful example is Hebrew, which was dead two centuries ago, before being revived and brought into the 20th century as a living language and the mother tongue of an entire generation of Israelis. Other languages have also been brought back from the brink of extinction through the sheer will and determination of their communities, including Welsh, Cornish, Gaelic and New Zealand Maori.

Language preservation works best when the language, culture and identity of minority-speaker communities are respected by national governments – rather than being banned, children are either fully taught in their mother tongue or given dedicated classes in it, in addition to learning the national or regional language. Evidence is mounting for the benefits of bi- or multi-lingualism, and for the social and psychological importance of mother-tongue conservation, which allows conversation across multiple generations and strengthens cultural continuity and community identity.

In some places, technology is proving an unlikely saviour. K. David Harrison, a linguist at Swarthmore College in Pennsylvania is creating 'talking dictionaries' of endangered languages that help users to preserve the tongues digitally though audio recordings of native speakers and pictures, and has a YouTube channel for endangered languages. The languages can then be used more easily for text messages over mobile phones, for example. "In some cases, people have created an orthography [script] for languages that have never been written down, so they can send SMS messages to each other," he says. So far, Harrison has created talking dictionaries in eight languages that have never previously been recorded including ones in Papua New Guinea, Siberia and Paraguay, and has six more dictionaries on the way.

One of the benefits of the globalised internet, Harrison says, is that remote villagers with endangered languages can reach a global audience. For example, a hiphop duo from a village in Arunachal Pradesh in northeast India, has garnered more than 9,000 global viewers for their YouTube video in the Aka language – that's more than ten times the number of Aka speakers.

The Hadza have now also had their language preserved in a dictionary by Kirk Miller, an American linguist who spent eight months living with them. It might be just in time. When we return from the bush hunt, a couple of the Hadza men try to sell me a bow and arrow, while some of the women string beads to sell to tourists. New cash from these enterprises is funding an unhealthy supply of alcohol that is eroding their culture as surely as the Tanzanian government's previous 'civilising' attempts. As communities cease to function productively, and individuals migrate away, fewer and fewer speakers will bear testimony to a way of life that was once practiced by the ancestors of us all.

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