❌

Normal view

There are new articles available, click to refresh the page.
Before yesterdayMain stream

Studies pin down exactly when humans and Neanderthals swapped DNA

12 December 2024 at 19:00

Two recent studies suggest that the gene flow (as the young people call it these days) between Neanderthals and our species happened during a short period sometime between 50,000 and 43,500 years ago. The studies, which share several co-authors, suggest that our torrid history with Neanderthals may have been shorter than we thought.

Pinpointing exactly when Neanderthals met H. sapiens Β 

Max Planck Institute of Evolutionary Anthropology scientist Leonardo Iasi and his colleagues examined the genomes of 59 people who lived in Europe between 45,000 and 2,200 years ago, plus those of 275 modern people whose ancestors hailed from all over the world. The researchers cataloged the segments of Neanderthal DNA in each person’s genome, then compared them to see where those segments appeared and how that changed over time and distance. This revealed how Neanderthal ancestry got passed around as people spread around the world and provided an estimate of when it all started.

β€œWe tried to compare where in the genomes these [Neanderthal segments] occur and if the positions are shared among individuals or if there are many unique segments that you find [in people from different places],” said University of California Berkeley geneticist Priya Moorjani in a recent press conference. β€œWe find the majority of the segments are shared, and that would be consistent with the fact that there was a single gene flow event.”

Read full article

Comments

Β© Sumer et al. 2024

Dog domestication happened many times, but most didn’t pan out

4 December 2024 at 22:16

Between 8,000 and 12,000 years ago, people in Alaska kept reinventing dogs with mixed results.

The dogs that share our homes today are the descendants of a single group of wolves that lived in Siberia about 23,000 years ago. But for thousands of years after that split, the line between wolf and dog wasn’t quite clear-cut. A recent study shows that long after dogs had spread into Eurasia and the Americas, people living in what is now Alaska still spent time withβ€”and fedβ€”a bizarre mix of dogs, wolves, dog-wolf hybrids, and even some coyotes.

We just can’t stop feeding the wildlife

University of Arizona archaeologist FranΓ§ois LanoΓ« and his colleagues studied 111 sets of bones from dogs and wolves from archaeological sites across the Alaskan interior. The oldest bones came from wolves that roamed what’s now Alaska long before people set foot there, and the most recent came from modern, wild Alaskan wolves. In between, the researchers worked with the remains of both wolves and dogs (and even a couple of coyotes) that span a swath of time from about 1,000 to around 14,000 years ago. And it turns out that even the wolves were tangled up in the lives of nearby humans.

Read full article

Comments

Β© Russell Burden

Ancient fish-trapping network supported the rise of Maya civilization

22 November 2024 at 18:40

On the eve of the rise of the Maya civilization, people living in what’s now Belize turned a whole wetland into a giant network of fish traps big enough to feed thousands of people.

We already know that the Maya turned swamps into breadbaskets by draining and building raised blocks of land for maize fields. However, a recent survey of a wetland in what’s now Belize suggests that the rise of the Maya civilization was fueled not just by maize but by tons of fish every year. University of New Hampshire archaeologist Eleanor Harrison-Buck and her colleagues recently mapped a network of channels and ponds for trapping fish, built just before the Maya civilization rose to prominence.

Fish in a barrel

Harrison-Buck and her fellow archeologists used drones and Google Earth data to map 108 kilometers of ancient channels that zigzag across 42 square kilometers of wetland in Belize’s Crooked Tree Wildlife Sanctuary. The result is a network of channels and ponds that looks remarkably like the fish traps found farther south in Bolivia, built several centuries after the ones at Crooked Tree. Radiocarbon dating of material buried in the bottom of one channel suggests that the network has been around for at least 4,000 years.

Read full article

Comments

Β© Fernando Flores

To invent the wheel, did people first have to invent the spindle?

18 November 2024 at 20:04

Twelve-thousand years ago, people in a coastal village in the Levant used stone weights on their spindles to spin thread faster and more evenlyβ€”and, some archeologists are arguing, in the process they pioneered the basic mechanics that eventually made cart wheels possible.

Archaeologists found hundreds of perforated, roundish, flattish pebbles in the 12,000-year-old village of Nahal Ein-Gev II, all with neat holes drilled in their centers. Based on their uneven appearance and their varied sizes, it seemed that these weren’t beads, but spindle whorls: a flywheel-like piece that makes a drop spindle spin faster and more steadily. The find is the oldest known evidence of a newfangled textile production technology called the drop spindle. But it may also have been a distant precursor to the wheel. According to archaeologists Talia Yashuv and Leore Grosman of the Hebrew University of Jerusalem, drop spindles work on the same mechanical principle as the earliest wheels, which show up on carts around 6,000 years ago during the Bronze Age.

β€œCircular objects with a hollowed center connected to a bar make one of the most important inventions of all time,” write Yashuv and Grosman in their recent paper. β€œAt the core of it all, the importance of the wheel and axle lies in a relatively simple rotational mechanism capable of transforming linear to rotary motion and vice versa.”

Read full article

Comments

Β© Yashuv and Grosman 2024

❌
❌