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Science is revolutionizing our understanding of the past.
Paleogenetics uncovers astonishing secrets of DNA hidden in bones and soil. Artificial intelligence decodes ancient texts written in forgotten scripts. Chemical analysis of molecular residues left on teeth, pots, incense burners and building materials reveals details about past diets, odors and building techniques.
Here are six mysteries about human history that scientists have solved in 2023. Plus, one that still has researchers scratching their heads.
The true identity of a prehistoric leader
Buried with a spectacular crystal dagger and other precious artifacts, the 5,000-year-old skeleton discovered in 2008 in a tomb near Seville, Spain, was clearly once someone important.
The individual was initially thought to be a young man, based on analysis of the pelvic bone, the traditional way scientists determine the sex of human skeletal remains.
However, an analysis of tooth enamel, which contains a type of protein with a sex-specific peptide called amelogenin, determined that the remains were female and not male.
In other studies, the technique has also dispelled the “hunting man” cliché that has informed much thinking about early humans.
“We believe that this technique is going to open a completely new era in the analysis of the social organization of prehistoric societies,” Leonardo García Sanjuán, a professor of prehistory at the University of Seville, told CNN in July when the discovery was made. made public.
The ingredient behind the legendary strength of Roman concrete
Roman concrete has proven to be more durable than its modern equivalent, which can deteriorate over decades. Take, for example, the Pantheon in Rome, which has the largest unreinforced dome in the world.
Scientists behind a study published in January said they had discovered the mysterious ingredient that allowed the Romans to make their building material so durable and build elaborate structures in challenging locations such as docks, sewers and seismic zones.
The study team analyzed 2,000-year-old concrete samples that were taken from a city wall at the Privernum archaeological site in central Italy and that are similar in composition to other concretes found throughout the Roman Empire.
They discovered that white bits in the concrete, known as lime clasts, gave the concrete the ability to heal cracks that formed over time. White chunks had previously been overlooked as evidence of sloppy mixing or poor-quality raw materials.
The real appearance of Ötzi the Iceman
Hikers found Ötzi’s mummified body in a ravine high in the Italian Alps in 1991. His frozen remains are perhaps the most studied archaeological find in the world, revealing in unprecedented detail what life was like 5,300 years ago.
The contents of his stomach have provided information about what his last meal was and where it came from, while his weapons showed that he was skilled and his clothing provided a rare look at what the ancients actually wore.
But a new analysis of DNA extracted from Ötzi’s pelvis revealed in August that his physical appearance was not what scientists first thought.
The study of his genetic makeup showed that Ötzi the Iceman had dark skin and eyes and was probably bald. This revised appearance contrasts sharply with Ötzi’s well-known reconstruction, which depicts a pale-skinned man with a full head of hair and a beard.
Wearer of 20,000-year-old pendant revealed
Archaeologists frequently unearth bone tools and other artifacts from ancient sites, but it has been impossible to know for sure who used or ever used them.
Earlier this year, scientists recovered ancient human DNA from a pendant made from deer bone found in the Denisova Cave in Siberia. With that clue they were able to reveal that its bearer was a woman who lived between 19,000 and 25,000 years ago.
He belonged to a group known as ancient northern Eurasians, who have a genetic connection to early Americans.
Human DNA was likely preserved in the deer bone pendant because it is porous and therefore more likely to retain genetic material present in skin cells, sweat, and other body fluids.
It is not known why the deer tooth pendant contained such a large amount of the ancient woman’s DNA (about the same amount as a human tooth). Perhaps it was loved and worn close to the skin for an exceptionally long period, said Elena Essel, a molecular biologist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, who developed a new technique for extracting DNA.
The ancient and damaged scroll decoded by AI
Some 1,100 scrolls were burned to ashes during the famous eruption of Vesuvius almost 2,000 years ago. In the 18th century, some enterprising excavators recovered the enormous treasure from the volcanic mud.
The collection, known as the Herculaneum scrolls, is perhaps the largest known library of classical antiquity, but the contents of the fragile documents remained a mystery until a University of Nebraska computer science student won a scientific competition in early this year.
With the help of artificial intelligence and CT imaging, Luke Farritor was the first to decode a word written in ancient Greek on one of those blackened scrolls.
Farritor received $40,000 for deciphering the word “πορφυρας” or “porphyras,” which in Greek means purple. Researchers are hopeful that it won’t be long until complete scrolls can be deciphered using this technique.
The materials needed to make a mummy.
Using fragments of vessels discarded in an embalming workshop, scientists have discovered some of the substances and concoctions that ancient Egyptians used to mummify the dead.
By chemically analyzing organic residue left in the vessels, researchers determined that ancient Egyptians used a wide variety of substances to anoint the body after death, reduce unpleasant odors, and protect it from fungi, bacteria, and putrefaction. The identified materials include vegetable oils such as juniper, cypress and cedar, as well as pistachio resins, animal fat and beeswax.
While scholars had previously learned the names of substances used to embalm the dead from Egyptian texts, until recently they could only guess exactly what compounds and materials they were referring to.
The ingredients used in the workshop were varied and came not only from Egypt, but from places much further away, suggesting long-distance exchange of goods.
Beethoven: a family secret is revealed, but a mystery remains
Composer Ludwig van Beethoven died at the age of 56 in 1827 after a series of chronic health problems, including hearing loss, gastrointestinal problems, and liver disease.
Beethoven wrote a letter to his brothers in 1802 requesting that his doctor, Johann Adam Schmidt, investigate the nature of the composer’s illnesses after he died. The letter is known as the Heiligenstadt Will.
Nearly 200 years after her death, scientists extracted DNA from preserved locks of hair in an attempt to fulfill this request.
The team was unable to reach a definitive diagnosis, but Beethoven’s genetic data helped researchers rule out possible causes of his condition, such as autoimmune celiac disease, lactose intolerance or irritable bowel syndrome.
Genetic information also suggested that an extramarital relationship had taken place in the composer’s family.
Ashley Strickland and Taylor Nicioli contributed to this report.
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