A Neanderthal skull
A Neanderthal skull
Stephane De Sakutin, AFP/Getty Images

Scientists May Have Finally Figured Out Why We Have Eyebrows

A Neanderthal skull
A Neanderthal skull
Stephane De Sakutin, AFP/Getty Images

If you look at a pictures of some of the earlier branches of humanity's family tree, like Neanderthals or Homo erectus, you might notice that Homo sapiens got off relatively lightly, eyebrow-wise. Most early hominins had thick, bony brow ridges rather than the smooth brows of modern humans. For years, researchers have been arguing over why those thick ridges existed—and why modern humans evolved tinier brows. A new study suggests that heavy brow ridges had social usefulness that was more important than their physiological function.

Previous research has suggested that thick brow ridges helped connect early hominins' eye sockets with their brain cavities, or protected the skull from the physical stress put on it by chewing jaws, or even helped early hominins take punches to the face.

The new study by University of York researchers, published in the journal Nature Ecology & Evolution, used a digital model of a fossil skull, thought to be between 125,000 and 300,000 years old, of an extinct species called Homo heidelbergensis that evolved sometime between 300,000 and 600,000 years ago in what is now Zambia. The researchers manipulated the model, changing the size of the brow ridge and seeing what happened when they applied different bite pressures. They found that the brow ridge was much bigger than it needed to be if its purpose was just to connect the eye sockets with the brain case, and that it didn't seem to protect the skull from the force of biting.

Instead, the researchers suggest that the brow ridge played a social role. Other primates have similar brow ridges that serve a social purpose rather than a mechanical one, like male mandrills, whose colorful, heavy-browed muzzles serve as dominance displays. Heavy brow ridges may have played a similar role in early human species.

As Homo sapiens evolved, more subtle communication may have taken precedence over the permanent social signal of a giant brow ridge. As foreheads became more vertical, eyebrows could move more freely and subtly, leading to important social signals in modern humans, like expressions of surprise or indignation.

An accompanying analysis in the same journal, by Spanish paleontologist Markus Bastir, cautions that the results of the new study are appealing, but should be taken with a grain of salt. The specimen used for the digital model was missing a mandible, and the researchers subbed in a mandible from a Neanderthal, a related species but still a distinct one from Homo heidelbergensis. This may have altered the analysis of the model and bite stresses. Still, the study provides "exciting prospects for future research," he writes.

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A Neanderthal skull
Romano D’Agostini, Giorgio Cargnel, Soprintendenza Speciale di Roma
Utility Workers May Have Found One of Rome’s First Churches
Romano D’Agostini, Giorgio Cargnel, Soprintendenza Speciale di Roma
Romano D’Agostini, Giorgio Cargnel, Soprintendenza Speciale di Roma

The remains of what may have been one of Rome’s earliest Christian churches were accidentally discovered along the Tiber River during construction, The Local reports. The four-room structure, which could have been built as early as the 1st century CE, was unearthed by electrical technicians who were laying cables along the Ponte Milvio.

The newly discovered structure next to the river
Romano D’Agostini, Giorgio Cargnel, Soprintendenza Speciale di Roma

No one is sure what to make of this “archaeological enigma shrouded in mystery,” in the words of Rome’s Archaeological Superintendency. Although there’s no definitive theory as of yet, experts have a few ideas.

The use of colorful African marble for the floors and walls has led archaeologists to believe that the building probably served a prestigious—or perhaps holy—function as the villa of a noble family or as a Christian place of worship. Its proximity to an early cemetery spawned the latter theory, since it's common for churches to have mausoleums attached to them. Several tombs were found in that cemetery, including one containing the intact skeleton of a Roman man.

Marble flooring
Romano D’Agostini, Giorgio Cargnel, Soprintendenza Speciale di Roma

A tomb
Romano D’Agostini, Giorgio Cargnel, Soprintendenza Speciale di Roma1

The walls are made of brick, and the red, green, and beige marble had been imported from Sparta (Greece), Egypt, and present-day Tunisia, The Telegraph reports.

As The Local points out, it’s not all that unusual in Rome for archaeological discoveries to be made by unsuspecting people going about their day. Rome’s oldest aqueduct was found by Metro workers, and an ancient bath house and tombs were found during construction on a new church.

[h/t The Local]

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A Neanderthal skull
Alexis Pantos, University of Copenhagen
Scientists Just Found the Oldest Known Piece of Bread
Alexis Pantos, University of Copenhagen
Alexis Pantos, University of Copenhagen

An old, charred piece of long-forgotten flatbread has captured the interest of archaeologists, anthropologists, and historians around the world. Found in a stone fireplace in Jordan’s Black Desert, this proto-pita dates back 14,400 years, making it the oldest known example of bread, Reuters reports.

To put the significance of this discovery in context: the flatbread predates the advent of agriculture by 4000 years, leading researchers to theorize that the laborious process of making the bread from wild cereals may have inspired early hunter-gatherers to cultivate grain and save themselves a whole lot of trouble.

“We now have to assess whether there was a relationship between bread production and the origins of agriculture,” Amaia Arranz-Otaegui, a researcher with the University of Copenhagen, told Reuters. “It is possible that bread may have provided an incentive for people to take up plant cultivation and farming, if it became a desirable or much-sought-after food.”

A report on these findings—written by researchers from the University of Copenhagen, University College London, and University of Cambridge—was published in the journal Proceedings of the National Academy of Sciences.

It was once thought that bread was an invention of early farming civilizations. A 9100-year-old piece of bread from Turkey was previously regarded as the oldest of its kind. However, the Jordanian flatbread was made by a group of hunter-gatherers called the Natufians, who lived during a transitional period from nomadic to sedentary ways of life, at which time diets also started to change.

Similar to a pita, this unleavened bread was made from wild cereals akin to barley, einkorn, and oats. These were “ground, sieved, and kneaded prior to cooking,” according to a statement from the University of Copenhagen. The ancient recipe also called for tubers from an aquatic plant, which Arranz-Otaegui described as tasting “gritty and salty."

[h/t Reuters]

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