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You Might Be a Neanderthal If...
New studies shed light on how Neanderthal DNA is affecting the appearance and behavior of modern humans.
Neanderthals, our ancient predecessors, who became extinct in Europe about 40,000 years ago, were found to interbreed with modern humans when both lived at the same time in Eurasia. As such, some Neanderthal genes found their way into our DNA, making up from 1 to 3 percent of the genetic code of humans who were not indigenous to Africa. As shows a new study from the Max Planck Institute for Evolutionary Anthropology in Germany, the Neanderthal code, while not large, may still be having a significant effect on how we look and feel.
The research team set out to figure out which specific elements of human appearance and behavior are linked to Neanderthal DNA. The scientists used information from the UK Biobank which made available genetic data on 112,338 individuals with white European ancestry (who have Neanderthal DNA), along with answers by the participants to questionnaires that included physical and behavioral descriptions. The researchers compared this to the genetic analysis of a Neanderthal specimen from the Altai mountains in Siberia.
The study's lead author computational biologist Michael Dannemann and co-author Janet Kelso discovered genetic links between Neanderthals and modern humans in traits like skin and hair color, sleeping patterns, mood and even tobacco use.
In particular, many of the connections were related to the adaptations to sunlight made by our genetic forefathers. They lived in Eurasia's sunlight conditions thousands of years before the arrival of modern humans and thus developed favorable genes to deal with the environment which they likely passed on to the humans through interbreeding.
Neanderthal cavemen hunting the cave bear. Circa 500000 BC. (Photo by Three Lions/Getty Images)
Being a night owl is one way you might get in touch with your Neanderthal roots, shows the research, as traits for staying up at night and napping during the day were found linked to Neanderthal DNA. So were moodiness and loneliness as well as propensity to smoke.
If you have red hair, you probably have little Neanderthal DNA in you as the data suggests red-headed Neanderthals were rare or maybe even non-existent.
How easily you get sunburned is another Neanderthal-linked characteristic, according to the scientists.
"Skin and hair color, circadian rhythms and mood are all influenced by light exposure," wrote the researchers. "We speculate that their identification in our analysis suggests that sun exposure may have shaped Neanderthal phenotypes and that gene flow into modern humans continues to contribute to variation in these traits today."
Read the new study here, in the American Journal of Human Genetics.
Another Neanderthal-related new study from researchers at the same Max Planck Institute, published in October in Science magazine, provides more evidence of how ancient DNA affects our health.
The team led by Svante Pääbo and Kay Prüfer made a detailed analysis of a Neanderthal woman who lived 52,000 years ago in Croatia. Through comparison, they found that the Neanderthal genome contributes to such health issues in modern people as blood cholesterol levels, schizophrenia, eating disorders as well as rheumatoid arthritis.
“These are just associations, so that doesn't mean if you have a particular variant of a gene, you either will or won't have a disease. It means sometimes you might," said Prüfer.
The studies contribute to the growing amount of knowledge about how Neanderthal genetics are affecting us. In further research, Danneman and Kelso, the scientists behind the study using Biobank data are looking to use the genome analyzed by their colleagues to repeat the research.
An open letter predicts that a massive wall of rock is about to plunge into Barry Arm Fjord in Alaska.
- A remote area visited by tourists and cruises, and home to fishing villages, is about to be visited by a devastating tsunami.
- A wall of rock exposed by a receding glacier is about crash into the waters below.
- Glaciers hold such areas together — and when they're gone, bad stuff can be left behind.
The Barry Glacier gives its name to Alaska's Barry Arm Fjord, and a new open letter forecasts trouble ahead.
Thanks to global warming, the glacier has been retreating, so far removing two-thirds of its support for a steep mile-long slope, or scarp, containing perhaps 500 million cubic meters of material. (Think the Hoover Dam times several hundred.) The slope has been moving slowly since 1957, but scientists say it's become an avalanche waiting to happen, maybe within the next year, and likely within 20. When it does come crashing down into the fjord, it could set in motion a frightening tsunami overwhelming the fjord's normally peaceful waters .
The Barry Arm Fjord
Camping on the fjord's Black Sand Beach
Image source: Matt Zimmerman
The Barry Arm Fjord is a stretch of water between the Harriman Fjord and the Port Wills Fjord, located at the northwest corner of the well-known Prince William Sound. It's a beautiful area, home to a few hundred people supporting the local fishing industry, and it's also a popular destination for tourists — its Black Sand Beach is one of Alaska's most scenic — and cruise ships.
Not Alaska’s first watery rodeo, but likely the biggest
Image source: whrc.org
There have been at least two similar events in the state's recent history, though not on such a massive scale. On July 9, 1958, an earthquake nearby caused 40 million cubic yards of rock to suddenly slide 2,000 feet down into Lituya Bay, producing a tsunami whose peak waves reportedly reached 1,720 feet in height. By the time the wall of water reached the mouth of the bay, it was still 75 feet high. At Taan Fjord in 2015, a landslide caused a tsunami that crested at 600 feet. Both of these events thankfully occurred in sparsely populated areas, so few fatalities occurred.
The Barry Arm event will be larger than either of these by far.
"This is an enormous slope — the mass that could fail weighs over a billion tonnes," said geologist Dave Petley, speaking to Earther. "The internal structure of that rock mass, which will determine whether it collapses, is very complex. At the moment we don't know enough about it to be able to forecast its future behavior."
Outside of Alaska, on the west coast of Greenland, a landslide-produced tsunami towered 300 feet high, obliterating a fishing village in its path.
What the letter predicts for Barry Arm Fjord
Moving slowly at first...
Image source: whrc.org
"The effects would be especially severe near where the landslide enters the water at the head of Barry Arm. Additionally, areas of shallow water, or low-lying land near the shore, would be in danger even further from the source. A minor failure may not produce significant impacts beyond the inner parts of the fiord, while a complete failure could be destructive throughout Barry Arm, Harriman Fiord, and parts of Port Wells. Our initial results show complex impacts further from the landslide than Barry Arm, with over 30 foot waves in some distant bays, including Whittier."
The discovery of the impeding landslide began with an observation by the sister of geologist Hig Higman of Ground Truth, an organization in Seldovia, Alaska. Artist Valisa Higman was vacationing in the area and sent her brother some photos of worrying fractures she noticed in the slope, taken while she was on a boat cruising the fjord.
Higman confirmed his sister's hunch via available satellite imagery and, digging deeper, found that between 2009 and 2015 the slope had moved 600 feet downhill, leaving a prominent scar.
Ohio State's Chunli Dai unearthed a connection between the movement and the receding of the Barry Glacier. Comparison of the Barry Arm slope with other similar areas, combined with computer modeling of the possible resulting tsunamis, led to the publication of the group's letter.
While the full group of signatories from 14 organizations and institutions has only been working on the situation for a month, the implications were immediately clear. The signers include experts from Ohio State University, the University of Southern California, and the Anchorage and Fairbanks campuses of the University of Alaska.
Once informed of the open letter's contents, the Alaska's Department of Natural Resources immediately released a warning that "an increasingly likely landslide could generate a wave with devastating effects on fishermen and recreationalists."
How do you prepare for something like this?
Image source: whrc.org
The obvious question is what can be done to prepare for the landslide and tsunami? For one thing, there's more to understand about the upcoming event, and the researchers lay out their plan in the letter:
"To inform and refine hazard mitigation efforts, we would like to pursue several lines of investigation: Detect changes in the slope that might forewarn of a landslide, better understand what could trigger a landslide, and refine tsunami model projections. By mapping the landslide and nearby terrain, both above and below sea level, we can more accurately determine the basic physical dimensions of the landslide. This can be paired with GPS and seismic measurements made over time to see how the slope responds to changes in the glacier and to events like rainstorms and earthquakes. Field and satellite data can support near-real time hazard monitoring, while computer models of landslide and tsunami scenarios can help identify specific places that are most at risk."
In the letter, the authors reached out to those living in and visiting the area, asking, "What specific questions are most important to you?" and "What could be done to reduce the danger to people who want to visit or work in Barry Arm?" They also invited locals to let them know about any changes, including even small rock-falls and landslides.
What makes some people more likely to shiver than others?
Some people just aren't bothered by the cold, no matter how low the temperature dips. And the reason for this may be in a person's genes.
Eating veggies is good for you. Now we can stop debating how much we should eat.
- A massive new study confirms that five servings of fruit and veggies a day can lower the risk of death.
- The maximum benefit is found at two servings of fruit and three of veggies—anything more offers no extra benefit according to the researchers.
- Not all fruits and veggies are equal. Leafy greens are better for you than starchy corn and potatoes.