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A surprising new study has revealed that diverse sounds produced by human speech not only evolved after Neolithic times but also stem from biological alterations in the human bite as a result of eating softer diets.

The findings contradict the theory that the range of human sounds has not changed since Homo sapiens emerged about 300,000 years ago. Linguistic diversity was also commonly thought to evolve independently of biological changes.

In 1985, linguist Charles Hockett suggested that labiodentals – the class of speech sounds including ‘f’ and ‘v’ in English – might have evolved as diets became softer with the move away from hunting and gathering towards agriculture and industrialized food processing.

These changes, he said, altered the human bite so that new sounds were easier to produce.

Damian Blasi and Steven Moran, researchers from the Department of Comparative Linguistics at the University of Zurich in Switzerland, thought the proposal was intriguing.

Their investigations revealed that labiodental sounds arose recently and that they did indeed stem from changes in diet and bite just as Hockett hypothesized.

“Soft diets led to the preservation of overbite and overjet, which characterizes the majority of the bites that people have nowadays,” Blasi explains. These rendered labiodental sounds low cost, or “easy” to produce.

“Since our upper teeth protrude from our mouth, they can touch the lower lips with very little effort,” he says.

“Before, heavy wear diets produced an edge-to-edge bite so the upper teeth didn’t protrude, and hence it was harder to produce those sounds. Try it yourself – put your upper and lower teeth in contact then try to produce an ‘f’.”

The team’s research suggests that the sounds originated not long before the Bronze Age in Europe and Asia. They suspect they emerged from bilabials, another class of speech sounds which include, for instance, ‘b’.

The authors explore how labiodentals might be “useful” sounds for communicating.

Read more at Cosmos Magazine

The latest study warning us to eat less meat has brought angry skeptics out in droves. But who should we believe?

Food, how to cook it, what it does to you and what growing or rearing it does to the planet are issues that crowd the media. And yet, as the clamor grows, clarity recedes. An estimated 820 million people went hungry last year, according to the UN Food and Agriculture Organisation. A third of all people were vitamin-deficient. Two billion were classified as overweight and 600 million as obese.

It’s also estimated that 1bn tonnes of food is wasted every year – a third of the total produced. A plethora of academic reports concerning food consumption and production have been published in recent years. The latest and arguably the most far-reaching is Food in the Anthropocene: the Eat-Lancet Commission on healthy diets from sustainable food systems, which was conducted over three years by 37 senior scientists from around the world and published earlier this year.

To combat the world’s growing demand for food – there will be 10 billion people to feed by 2050 – we need to cut meat almost entirely out of our diet, say the authors of the report. The argument they put forward is that eating more plant-based foods will lower the incidences of heart disease, diabetes, and cancer, enable more environmentally helpful use of land and reduce carbon emissions.

The report provides a “planetary health diet” based on eating vegetables, grains, pulses and nuts, which limits red meat to one serving a week and other animal protein to greatly reduced amounts, as little as an ounce a day of fish or chicken. This, say the authors, is what we should all be eating if we’re concerned about our health and that of the planet.

In fact, the report was wholly financed by the Wellcome Trust, which is also a participant in Eat, which supplied staff, but they were paid for by Wellcome Trust.

Another criticism Blythman raised was the prospect of “cranky diets and nutritional deficiencies in affluent countries and acute protein shortages in the poorer ones”. She’s not alone, with many bloggers weighing in to question Eat-Lancet’s findings. One critic was Zoë Harcombe, who has a Ph.D. in public health nutrition and has previously questioned dietary fat guidelines. Harcombe said that the Eat-Lancet diet was “nutritionally deficient” in vitamins B12, D, sodium, potassium, and iron.

More of this story at The Guardian