CLOSE
Original image
Skull of a Neolithic farmer // Image Credit: Daniel Bradley, Trinity College Dublin

Human Remains Found Under Pub May Help Rewrite Irish History

Original image
Skull of a Neolithic farmer // Image Credit: Daniel Bradley, Trinity College Dublin

It’s easy to imagine history as a static, objective truth: here’s what happened. But history is more like a tree: a growing understanding pruned by certain hands, changing as we learn more about the past. That’s what’s happening now, as new DNA evidence from human remains found in Ireland upends long-held ideas about the ancient Celts. A report of these findings was recently published in the Proceedings of the National Academy of Sciences.

Researchers sequenced the genomes of four human bodies, three of which were discovered behind a pub in County Antrim, Northern Ireland. Pub owner Bertie Currie was in the process of digging out a new driveway when he uncovered a big, flat stone. Currie moved the stone aside and was horrified to find human bones. "I shot the torch in and saw the gentleman, well, his skull and bones," Currie said this week, as reported by The Washington Post.

Alarmed, Currie called the police, but the bones were not recent—not by a long shot. Archaeologists say the men interred in Currie’s yard had been there since the Bronze Age. Their remains, along with those of a Neolithic woman found near Belfast, have shaken up the long-established timeline of Irish history.

For centuries, the story has been the same: Between the years 1000 and 500 BCE, invading Celts crossed from central Europe into Ireland, where they settled, made babies, and created the Irish people.

But the four subjects of the recent research tell a very different story. The paper’s authors say the DNA bears a “striking” resemblance to that of modern Irish—but their bones predate the supposed arrival of the Celts by more than 1000 years.

“The genomes of the contemporary people in Ireland are older—much older—than we previously thought,” senior author Dan Bradley said.

The researchers were able to determine that the woman, who was most likely a farmer, had black hair and brown eyes, like southern Europeans.

Reconstruction of the farmer's face by Elizabeth Black. Image credit: Barrie Hartwell

The men’s DNA included two key gene variants: one for blue eyes and another for a condition called haemochromatosis, in which iron slowly builds up in the body until it reaches toxic levels. The allele (gene variant) for haemochromatosis is so common in Irish people that it is sometimes called "the Celtic curse."

This study is not the first to suggest a new timeline for Celtic history, but it does present some of the most compelling evidence.

Archaeologist Barry Cunliffe is unaffiliated with the study, but he believes it has huge implications; he argued in a 2001 book that archaeological evidence points to a migration of peoples into Europe from its Western, Atlantic edge. “If [proponents of this theory are] right,” he told The Washington Post, “the roots of what is known as ‘Celtic’ culture go way way back in time. And the genetic evidence is going to be an absolute game-changer.”

[h/t The Washington Post]

Original image
iStock
arrow
Food
Researchers Pinpoint the Genes Behind the Durian's Foul Stench
Original image
iStock

Durian is a popular fruit in parts of southeast Asia. It's also known for having the most putrid, off-putting odor of any item sold in the produce section. Even fans of durian know why the fruit gets a bad rap, but what exactly causes its divisive scent is less obvious. Determined to find the answer, a team of researchers funded by "a group of anonymous durian lovers" mapped the fruit's genome, as reported by the BBC.

The study, published in the journal Nature Genetics [PDF], contains data from the first-ever complete genetic mapping of a durian fruit. It confirms that durian's excess stinkiness comes from sulfur, a chemical element whose scent is often compared to that of rotten eggs.

Analysis of the fruit's chemical makeup has been done in the past, so the idea that sulfur is a major contributor to its signature smell is nothing new. What is new is the identification of the specific class of sulfur-producing genes. These genes pump out sulfur at a "turbocharged" rate, which explains why the stench is powerful enough to have durian banned in some public areas. It may seem like the smell is a defense mechanism to ward off predators, but the study authors write that it's meant to have the opposite effect. According to the paper, "it is possible that linking odor and ripening may provide an evolutionary advantage for durian in facilitating fruit dispersal." In other words, the scent attracts hungry primates that help spread the seeds of ripe durian fruits by consuming them.

The revelation opens the door to genetically modified durian that are tweaked to produce less sulfur and therefore have a milder taste and smell. But such a product would likely inspire outrage from the food's passionate fans. While the flavor profile has been compared to rotten garbage and dead animal meat, it's also been praised for its "overtones of hazelnut, apricot, caramelized banana, and egg custard" by those who appreciate its unique character.

[h/t BBC]

Original image
iStock
arrow
science
Why DNA Is So Hard to Visualize
Original image
iStock

Picture a strand of DNA and the image you see will likely be similar to the artist’s rendering above. The iconic twisted ladder, or double-helix structure, was first revealed in a photo captured by Rosalind Franklin in the 1950s, but this popular visualization only tells part of the story of DNA. In the video below, It’s Okay to Be Smart explains a more accurate way to imagine the blueprints of life.

Even with sophisticated lab equipment, DNA isn’t easy to study. That’s because a strand of the stuff is just 2 nanometers wide, which is smaller than a wavelength of light. Researchers can use electron microscopes to observe the genetic material or x-rays like Rosalind Franklin did, but even these tools paint a flawed picture. The best method scientists have come up with to visualize DNA as it exists inside our cells is computer modeling.

By rendering a 3D image of a genome on a computer, we can see that DNA isn’t just a bunch of free-floating squiggles. Most of the time the strands sit tightly wound in a well-organized web inside the nucleus. These balls of genes are efficient, packing 2 meters of DNA into a space just 10 millionths of a meter across. So if you ever see a giant sculpture inspired by an elegant double-helix structure, imagine it folded into a space smaller than a shoe box to get closer to the truth.

[h/t It’s Okay to Be Smart]

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios