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.

Remains of Late 19th-Century Shipwreck Found on Jersey Shore

iStock.com/Sierra Gaglione
iStock.com/Sierra Gaglione

The holiday season isn't usually associated with the beach, but nature has a funny way of delivering surprises no matter the time of year. The weekend before Christmas, the remains of an old ship stretching over 25 feet long were discovered at the southern area of Stone Harbor beach, according to nj.com.

Local historians believe the vessel is the D.H. Ingraham, a schooner that sank in 1886 during a voyage from Rockland, Maine, to Richmond, Virginia. Archives from the time recount that while the ship was delivering a cargo of lime, it caught fire. Thanks to station employees at the nearby Hereford Lighthouse, all five men aboard were rescued and given proper shelter for the next four days. The rescuers even received medals of honor from Congress, which are still on display inside the lighthouse, according to the Press of Atlantic City.

This is not the only shipwreck to have been discovered along the Jersey Shore; in 2014, the U.S. Army Corps of Engineers found one while making repairs to the Barnegat Inlet jetty. (New Jersey has its own Historical Divers Association, and at one point its president, Dan Lieb, estimated that the state had up to 7000 shipwrecks off its coasts.)

To check out more coverage about shipwrecks, like this 48-foot find in Florida earlier this year, click here.

[h/t nj.com]

People Have Been Dining on Caviar Since the Stone Age

iStock.com/Lisovskaya
iStock.com/Lisovskaya

Millennia before caviar became a staple hors d'oeuvre at posh parties, it was eaten from clay pots by Stone Age humans. That's the takeaway of a new study published in the journal PLOS One. As Smithsonian reports, traces of cooked fish roe recovered from an archeological site in Germany show just how far back the history of the dish goes.

For the study, researchers from Germany conducted a protein analysis of charred food remains caked to the shards of an Stone Age clay cooking vessel. After isolating roughly 300 proteins and comparing them to that of boiled fresh fish roe and tissue, they were able to the identify the food scraps as carp roe, or eggs. The scientists write that the 4000 BCE-era hunter-gatherers likely cooked the fish roe in a pot of water or fish broth heated by embers, and covered the pot with leaves to contain the heat or add additional flavor.

The clay shards were recovered from Friesack 4 in Brandenburg, Germany, a Stone Age archaeological site that has revealed about 150,000 artifacts, including items crafted from antlers, wood, and bone, since it was discovered in the 1930s. In the same study, the researchers report that they also found remnants of bone-in pork on a vessel recovered from the same site.

Other archaeological digs have shown that some of the foods we think of as modern delicacies have been around for thousands of years, including cheese, salad dressing, and bone broth. The same goes for beverages: Recently a 13,000-year-old brewery was uncovered in the Middle East.

[h/t Smithsonian]

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