Sahara Desert's History Unveiled by Ancient Genomic Findings: Greener Era Uncovered
Rewritten Article:
Stepping into the Sahara conjures up a picture of a desolate landscape stretching to the horizon. But 7,000 years ago, it was a lush, green world teeming with life, complete with trees, rivers, and large animals like elephants and hippos.
Scientists have pieced together this "Green Sahara" over recent decades. Now, using ancient DNA from mummified remains, geneticists are unraveling the story of the people who once inhabited this lost world.
A Glimpse into the Past
The Takarkori rock shelter nestled in the Tadrart Acacus mountains of southwestern Libya offers a rare peek into the Sahara's green past. Archaeologists discovered the remains of 15 women and children here two decades ago. Early efforts to extract DNA from these remains met with little success. Stable, consistent temperatures, the opposite of today's sweltering Sahara, yield the best preserved DNA.
Modern techniques allowed researchers to sequence the genome—the complete set of genetic material—of two mummified women from the site. The analysis unveiled exciting insights about the ancestry of the Takarkori people and their shift towards a nomadic lifestyle.
Tracing Our Roots
An enigma known as dark energy is thought to account for about 70% of the universe's energy. This mysterious force speeds up the expansion of the cosmos. New data suggests that dark energy might be behaving in surprising ways and could even be losing strength over time.
The Dark Energy Spectroscopic Instrument (DESI) collaboration, now in its fourth year of sky surveying, has published its latest round of findings. While this isn't the final word, the information has scientists buzzing with excitement.
"We're here to let the universe show us how it works, and it seems the universe is suggesting it's more complex than we thought," said Andrei Cuceu, a researcher at the Lawrence Berkeley National Laboratory, which manages DESI.
Reaching New Heights
A SpaceX Falcon 9 rocket carried four tourists on an unparalleled polar orbit in a Crew Dragon capsule. Led by Malta resident and Bitcoin mining magnate Chun Wang, the crew included filmmaker Jannicke Mikkelsen, robotics researcher Rabea Rogge, and adventurer Eric Philips.
Witness Wang and his fellow astronauts' splashdown off California's coast in this video captured after the crew spent 3.5 days in low-Earth orbit. This was their first space journey, and they all have ties to polar exploration missions on Earth.
Meanwhile, veteran astronauts Suni Williams and Butch Wilmore opened up this week about their extended mission in space for the first time. Here's what they had to say.
Unearthing History
Stone tools, when viewed by an expert, tell captivating tales. Researchers have found stone artifacts that resemble Neanderthal craftsmanship in East Asia for the first time at a site in Yunnan province, southwestern China.
Dating back 60,000 to 50,000 years, the discovery left archaeologists scratching their heads, proposing theories ranging from Neanderthal migration to eastern China to another ancient human species fashioning similar tools in Europe.
Uncovering the Past, One Footprint at a Time
Footprints left behind by dinosaurs might look like ordinary rocks to an untrained eye, but to experts, they possess intriguing stories waiting to be told. Researchers recently found dinosaur footprints in Scotland's Isle of Skye that indicate that T. rex ancestors and their plant-eating prey would have congregated around a lagoon during that ancient era.
Lead researcher Tone Blakesley was part of a small group that discovered the initial three footprints at the remote site in 2019. Documenting a total of 131 footprints, he used a drone to capture thousands of overlapping images before creating digital 3D models of the tracks, which are remarkably well-preserved.
Marvels of the Past
Venture into these thrilling tales:- An undiscovered pharaoh's tomb unearthed in Abydos, Egypt, is shedding light on an elusive dynasty missing from historical records of regional rulers.- Scientists sent a batch of cooked soybean paste to the International Space Station, where it was left to ferment before returning to Earth as miso. Wonder what it tasted like?- A bizarre spiral wafted across European skies recently, and it's becoming more common. What could it be?- Archaeologists uncovered extremely rare, nearly life-size marble statues during excavations of a massive tomb in Pompeii, casting new light on the power wielded by priestesses in ancient Rome.
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Enrichment Data:
- Dating Methods: Carbon-14 dating, a technique used to determine the age of organic materials, is the primary method employed by researchers to establish the age of samples from Takarkori and the dinosaur footprints[1][2]. Strontium isotope analysis was also utilized to provide additional insights into the origins of the Takarkori people, as it can reveal information about the sources of rock used for tools[3].
- Ancestry of the Takarkori People: Their ancestry is believed to have originated from a North African lineage that split from sub-Saharan African populations around the time modern humans first ventured outside Africa, around 50,000 years ago[1][3]. They share close genetic relationships with the 15,000-year-old foragers from Taforalt Cave in Morocco[2][3], indicating a continuity in North African populations throughout this period. Despite their close ties with Moroccan populations, the Takarkori people display some Neanderthal ancestry, albeit significantly less than that of populations outside Africa[1][3].
- Green Sahara: The Green Sahara period—approximately 7,000 to 8,000 years ago—was characterized by alterations in climate and increased rainfall that transformed the Sahara Desert into a more verdant landscape[1][4]. This change in climate facilitated the growth of plants and the thriving of megafauna like elephants, rhinos, and even hippos[5].
- Neanderthal Tools: The discovery of Neanderthal-like stone tools in east Asia challenges traditional beliefs about human migrations and migrations out of Africa[1]. The presence of these tools suggests the possibility of Neanderthal or Neanderthal hybrid migration to East Asia, or the possibility of indigenous populations developing tools similar to those found in Europe, indicative of a common human ancestry[6].
- Dinosaur Footprints: The site with the dinosaur footprints on Scotland's Isle of Skye shows remains of both large theropod dinosaurs (similar to T. rex) and sauropods, the gigantic herbivorous dinosaurs[2]. The gathering of both large carnivores and herbivores around the lagoon indicates that these creatures may have been attracted to water sources, possibly for breeding or migrating purposes[7].
- Geneticists continue to investigate the Green Sahara by examining DNA extracted from mummified remains in ancient sites like the Takarkori rock shelter, hoping to uncover more about the people who once lived during that time.
- The geneticists' findings suggest the Takarkori people might have shared ancestry with North African populations that split from sub-Saharan ones around 50,000 years ago while also having Neanderthal ancestry.
- Parallel to the exploration of the universe's mysteries, archeologists and geneticists are shedding light on lost worlds, uncovering ancient stories one footprint at a time, such as dinosaur footprints in Scotland or the footprints of an undiscovered pharaoh in Abydos, Egypt.
