Tag: life

How People Really Lived During the Stone Age

cave man

The Paleo diet is just the beginning. It’s the gateway to an entire suite of lifestyle prescriptions devoted to mimicking the way our ancestors ate, moved, slept, and bred nearly 10,000 years ago in the Paleolithic era of hunting and gathering, an era Paleo followers associate with strong bodies and minds.

Members of this modern-day caveman community believe the path to optimal health is through eating only what our ancestors ate before modern agriculture and a shift to more sedentary ways.




Devoted proponents of a Paleo lifestyle not only subsist primarily on meat and eschew carbs; they also exercise in short bursts of activity intended to mimic escaping prey.

Even blood donation has become a Paleo fad among the most dogmatic of 21st-century cavemen, based on the notion that our ancestors were often wounded, making blood loss a way of life.

But new research reveals flaws in the logic behind these trends. As evolutionary and genetic science show, humans, like all other living beings, have always been a work in progress and never completely in sync with the natural world.

Survive-in-the-wild

If we’re going to romanticize and emulate a particular point in our evolutionary history, why not go all the way back to when our ape ancestors spent their days swinging from tree to tree?

It is hard to argue that a simpler life with more exercise, fewer processed foods, and closer contact with our children may well be good for us, but rather than renouncing modern living for the sake of our Stone Age genes, we need to understand how evolution has—and hasn’t—suited us for the world we inhabit now.

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Oldest Fossils Of Homo Sapiens Found in Morocco

jaw

Fossils discovered in Morocco are the oldest known remains of Homo sapiens, scientists reported, a finding that rewrites the story of mankind’s origins and suggests that our species evolved in multiple locations across the African continent.

Until now, the oldest known fossils of our species dated back just 195,000 years. The Moroccan fossils, by contrast, are roughly 300,000 years old.




Remarkably, they indicate that early Homo sapiens had faces much like our own, although their brains differed in fundamental ways.

Today, the closest living relatives to Homo sapiens are chimpanzees and bonobos, with whom we share a common ancestor that lived over six million years ago.

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Water On Mars: Exploration & Evidence

Liquid water may still flow on Mars, but that doesn’t mean it’s easy to spot. The search for water on the Red Planet has taken more than 15 years to turn up definitive signs that liquid flows on the surface today.

In the past, however, rivers and oceans may have covered the land. Where did all of the liquid water go?

Why? How much of it still remains?




Liquid water appears to flow from some steep, relatively warm slopes on the Martian surface.

Features known as recurring slope lineae (RSL) were first identified in 2011in images taken by the High Resolution Imaging Science Experiment (HiRISE) camera aboard the Mars Reconnaissance Orbiter (MRO).

The dark streaks, which appear seasonally, were confirmed to be signs of salty water running on the surface of the planet.

If this is correct, then RSL on Mars may represent the surface expression of a far more significant ongoing drainage system on steep slopes in the mid-latitudes,” a research team member said.

In 2015, spectral analysis of RSL led scientists to conclude they are caused by salty liquid water.

When Mariner 9 became the first craft to orbit another planet in 1971, the photographs it returned of dry river beds and canyons seemed to indicate that water had once existed on the Martian surface.

Images from the Viking orbiters only strengthened the idea that many of the landforms may have been created by running water.

Data from the Viking landers pointed to the presence of water beneath the surface, but the experiments were deemed inconclusive.

The early ’90s kicked off a slew of Mars missions. Scientists were flooded with a wealth of information about Mars.

Three NASA orbiters and one sent by the European Space Agency studied the planet from above, mapping the surface and analyzing the minerals below.

Some detected the presence of minerals, indicating the presence of water. Other data measured enough subsurface ice to fill Lake Michigan twice.

They found evidence for the presence of hot springs on the surface and sustained precipitation at some areas. And they found patches of ice within some of the deeper craters.

Impact craters offer a view of the interior of the red planet.

Using the ESA’s Mars Express and NASA’s Mars Reconnaissance Orbiter, scientists were able to study rocks ejected from the planet’s interior, finding minerals that suggested the presence of water.

Curiosity has found yet more evidence of water flowing on ancient Mars.

The 1-ton rover rolled through an ancient stream bed shortly after touching down in August 2012, and it has examined a number of rocks that were exposed to liquid water billions of years ago.

Mars missions aren’t the only way to search for water on Mars. Scientists studying rocks ejected from the Red Planet found signs that water lay beneath the surface in the past.

While robotic missions to Mars continue to shed light on the planet’s history, the only samples from Mars available for study on Earth are Martian meteorites,” lead author Lauren White, of the JPL, said in a statement.

On Earth, we can utilize multiple analytical techniques to take a more in-depth look at meteorites and shed light on the history of Mars.

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Meet The Snot-Dwelling Sea Creatures Who Help Move Food Through The Ocean

Hundreds of feet below the ocean’s surface, animals smaller than the palm of your hand make their houses out of snot.

These bizarro creatures called larvaceans keep the oceans teeming with life by gobbling up anything nutritious that’s floated down from the surface.

These little guys, which are shaped like tadpoles, filter a truly shocking amount of water in a single hour — between two and four of those giant five-gallon water jugs that get delivered to your office, according to a study in the journal Science Advances.




Giant larvaceans could push all of the water around them in Monterey Bay through their filters within 500 days; if a lot of them were all together and working as hard as they could, they could filter that same volume of water in just 13 days.

In order to find out exactly how these mysterious mucus-dwellers work, scientists at the Monterey Bay Aquarium Research Institute outfitted a remote-controlled vehicle with an arm wielding a laser to light up the food particles, and trained it on the giant larvaceans as they pumped water through their mucus and into their mouths.

A video camera on the vehicle recorded the flow, and the scientists published their findings today in the journal Science Advances.

The nutrients that don’t go toward keeping these creatures alive and in luxurious mucus homes get pooped onto the seafloor. And if the snot houses get too clogged up, the larvaceans simply drop them.

There, the poop and old mucus-shrouds feed bottom-dwelling sea creatures. It’s like a giant, oceanic, digestive system where nothing gets wasted — and where food gets grosser as it travels downward.

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Solar Tornadoes As Big As The US Heat Sun’s Atmosphere

For years, scientists have struggled to determine why the sun’s atmosphere is more than 300 times hotter than its surface. But a new study has found a possible answer: giant super-tornadoes on the sun that may be injecting heat into the outer layers of our star.

While comparing images from the Swedish Solar Telescope with others taken by NASA’s Solar Dynamics Observatory, an international team of scientists noticed bright points on the sun’s surface and atmosphere that corresponded with swirls in the so-called chromospheres, a region that is sandwiched between the two layers.

The finding indicates that  the solar tornadoes stretched through all three layers of the sun.

The scientists went on to identify 14 solar super-tornadoes occurring within an hour of each other. By using a three dimensional simulation, the team then found that the swirls could play a role in elevating the sun’s outer layer.

Unlike tornadoes on Earth, which are powered by differences in temperature and humidity, the twisters on the sun are a combination of hot flowing gas and tangled magnetic field lines, ultimately driven by nuclear reactions in the solar core.




At the surface, or photosphere, cooled plasma sinks toward the interior like water running down the bathtub drain, creating vortexes that magnetic field lines are forced to follow. The lines stretch upward into the chromosphere, where they continue to spiral.

But while the hot gas at the surface drives the movement of the magnetic field, in the chromosphere it is the field lines that force the hot gas to spiral, creating the swirls that appear similar to tornadoes on Earth.

Spinning at thousands of miles per hour, the tornadoes vary in size, with diameters ranging from 930 to 3,500 miles (1,500 to 5,550 kilometers). Some of these giant solar twisters extend all the up in to the lower portion of the sun’s upper atmosphere (called the corona, the researchers said.

Although the twisters are enormous by Earth’s scale, they are tiny on the surface of the sun.

They were first detected in 2008 by Wedemeyer-Böhm and another researcher, but it wasn’t until images of super-tornadoes were compared with those from the corona and photosphere that scientists realized how high the writhing gas extended — or the influence they could have on the sun’s temperature.

The surface temperature of the sun is 9,980 Fahrenheit (5,526 degrees Celsius or about 5,800 Kelvin), while the corona peaks at 3.5 million Fahrenheit (2 million degrees Celsius or nearly 2 million Kelvin), a fact that seems counter-intuitive.

After observing the sun, the international team created computer models in an attempt to determine how much energy — and thus heat — could be effectively transported by the twisters.

They concluded that solar tornadoes could help to explain how the outer layer stays so hot, although Wedemeyer-Böhm notes that it is likely only one of a number of different processes powering the temperature of the sun’s corona.

The tornadoes differ from those spotted earlier this year. Those much larger events were formed by twisting solar prominences, and were likely connected to mass ejected from the sun.

The smaller tornadoes are more abundant, and make a more significant contribution to the corona’s temperature.

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Working An Occasional Night Shift Could Kill You

Working an occasional night shift for a prolonged period could ultimately kill you, according to a major new study.

Researchers in the US looked at the medical records of about 189,000 women over a 24-year period and found a significant link between ‘rotating’ shift patterns, in which people alternate between night and day work, and coronary heart disease (CHD).

They suggested further work should be done to find out if shift patterns could be altered to reduce the risks.

Scientists have reported the adverse health effects of working night shifts before but the sheer size of this study underlines the extent of the problem.




Dr Celine Vetter, lead author of a paper in the Journal of the American Medical Association (JAMA), said: “There are a number of known risk factors for coronary heart disease, such as smoking, poor diet, lack of physical activity, and elevated body mass index. 

These are all critical factors when thinking how to prevent CHD. However, even after controlling for these risk factors, we still saw an increased risk of CHD associated with rotating shift work.

They found that those who worked three or more night shifts a month for a decade had a 15 to 18 per cent higher chance of getting the disease than those who did not have a rotating shift pattern  – an effect they described as “modest”.

They said their findings were applicable only to women as occasional shift work might affect men differently.

It is important to note that this is a modifiable risk factor, and changing shift schedules may have an impact on the prevention of CHD,” said Dr Vetter, an epidemiologist at Brigham and Women’s Hospital in Boston.

Our results are in line with other findings, yet, it is possible that different schedules might carry a different risk — and we have very little information on exact schedules — as well as work start and end times. 

We believe that the results from our study underline the need for future research to further explore the relationship between shift schedules, individual characteristics and coronary health to potentially reduce CHD risk.

The researchers used information from the US Nurses’ Health Study in which they reported everything from heart attacks to CHD-related chest pain. Fatalities from CHD were confirmed by death certificates.

Over the 24-year period of the study, more than 10,000 women developed the disease.

It has been suggested that changing shifts can disrupt people’s body clock, which operates on a rough 24-hour cycle.

Circadian misalignment – where the [the body’s natural rhythm is out of step] with behavioural cycles of activity, sleep and food intake – may be a key mechanism linking shift work to chronic disease, including cardiovascular disease,” the researchers wrote in the JAMA paper.

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TRAPPIST-1 Planets Probably Rich In Water

Planets around the faint red star TRAPPIST-1, just 40 light-years from Earth, were first detected by the TRAPPIST-South telescope at ESO’s La Silla Observatory in 2016.

In the following year further observations from ground-based telescopes, including ESO’s Very Large Telescope and NASA’s Spitzer Space Telescope, revealed that there were no fewer than seven planets in the system, each roughly the same size as the Earth.

They are named TRAPPIST-1b,c,d,e,f,g and h, with increasing distance from the central star.

Further observations have now been made, both from telescopes on the ground, including the nearly-complete SPECULOOS facility at ESO’s Paranal Observatory, and from NASA’s Spitzer Space Telescope and the Kepler Space Telescope.

A team of scientists led by Simon Grimm at the University of Bern in Switzerland have now applied very complex computer modelling methods to all the available data and have determined the planets’ densities with much better precision than was possible before.




Simon Grimm explains how the masses are found: “The TRAPPIST-1 planets are so close together that they interfere with each other gravitationally, so the times when they pass in front of the star shift slightly.

“These shifts depend on the planets’ masses, their distances and other orbital parameters. With a computer model, we simulate the planets’ orbits until the calculated transits agree with the observed values, and hence derive the planetary masses.”

Team member Eric Agol comments on the significance: “A goal of exoplanet studies for some time has been to probe the composition of planets that are Earth-like in size and temperature.

“The discovery of TRAPPIST-1 and the capabilities of ESO’s facilities in Chile and the NASA Spitzer Space Telescope in orbit have made this possible — giving us our first glimpse of what Earth-sized exoplanets are made of!

The measurements of the densities, when combined with models of the planets’ compositions, strongly suggest that the seven TRAPPIST-1 planets are not barren rocky worlds.

They seem to contain significant amounts of volatile material, probably water, amounting to up to 5% the planet’s mass in some cases — a huge amount; by comparison the Earth has only about 0.02% water by mass!

TRAPPIST-1b and c, the innermost planets, are likely to have rocky cores and be surrounded by atmospheres much thicker than Earth’s.

TRAPPIST-1d, meanwhile, is the lightest of the planets at about 30 percent the mass of Earth. Scientists are uncertain whether it has a large atmosphere, an ocean or an ice layer.

Scientists were surprised that TRAPPIST-1e is the only planet in the system slightly denser than Earth, suggesting that it may have a denser iron core and that it does not necessarily have a thick atmosphere, ocean or ice layer.

It is mysterious that TRAPPIST-1e appears to be so much rockier in its composition than the rest of the planets.

In terms of size, density and the amount of radiation it receives from its star, this is the planet that is most similar to Earth.

TRAPPIST-1f, g and h are far enough from the host star that water could be frozen into ice across their surfaces.

If they have thin atmospheres, they would be unlikely to contain the heavy molecules that we find on Earth, such as carbon dioxide.

Astronomers are also working hard to search for further planets around faint red stars like TRAPPIST-1. As team member Michaël Gillon explains: “This result highlights the huge interest of exploring nearby ultracool dwarf stars — like TRAPPIST-1 — for transiting terrestrial planets.

“This is exactly the goal of SPECULOOS, our new exoplanet search that is about to start operations at ESO’s Paranal Observatory in Chile.

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Titan Could Have “Crystals” On Its Surface That Can Support Alien Life

Scientists say there may be crystals on Titan that could provide food for some forms of alien life, according to a study published in the journal ACS Earth and Space Chemistry.

Known as “co-crystals”, they are thought to be the result of ammonia and acetylene creating a salt-like compound, caused by Titan’s methane rain and ethane flooding.

Co-crystals are basically salts that are made of two or more molecular compounds. This allows for some unique properties, such as a different melting point to the original compounds.

However, there is some disagreement over what exactly one is.




The importance of these co-crystals is that they could provide food on Titan’s surface for microbial life.

Some composed of benzene and ethane have been proposed before, but this new type of co-crystal forms more quickly and should be able to survive Titan’s weather.

These co-crystals, or ‘organic minerals’, are an exciting new class of compounds for Titan’s surface,” Morgan Cable from NASA’s Jet Propulsion Laboratory (JPL), the study’s lead author said.

The crystals would be extremely small, just a few microns in size – which is smaller than the width of human hair.

They may grow larger under the right conditions, with Cable noting they could look like fresh snow. What’s more, they could be food for certain types of microbes.

Titan has been a bit of a hot topic lately, with NASA currently considering sending a quadcopter to the surface, flying over the ground to study dozens of sites – including the moon’s lakes and seas of liquid hydrocarbons.

It would launch in 2025 and arrive in 2034.

A recent study also found that Titan’s oceans may be suitable for a submarine at some point in future.

Replicating the temperature and pressure of Titan in the lab, they found that despite the tough conditions, we could feasibly explore these regions.

Titan is the only place other than Earth with known bodies of liquid on its surface. Coupled with its thick atmosphere, it looks like quite an enticing environment for life in one form or another.

Whether it’s truly habitable we might not know for a while, but perhaps these crystals on the surface could help play a part.

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Why Can’t We Feel Earth’s Spin?

Earth spins on its axis once in every 24-hour day. At Earth’s equator, the speed of Earth’s spin is about 1,000 miles per hour (1,600 kph).

The day-night has carried you around in a grand circle under the stars every day of your life, and yet you don’t feel Earth spinning.

Why not? It’s because you and everything else – including Earth’s oceans and atmosphere – are spinning along with the Earth at the same constant speed.

It’s only if Earth stopped spinning, suddenly, that we’d feel it. Then it would be a feeling similar to riding along in a fast car, and having someone slam on the brakes!




Think about riding in a car or flying in a plane. As long as the ride is going smoothly, you can almost convince yourself you’re not moving.

A jumbo jet flies at about 500 miles per hour (about 800 km per hour), or about half as fast as the Earth spins at its equator. But, while you’re riding on that jet, if you close your eyes, you don’t feel like you’re moving at all.

And when the flight attendant comes by and pours coffee into your cup, the coffee doesn’t fly to the back of the plane. That’s because the coffee, the cup and you are all moving at the same rate as the plane.

Now think about what would happen if the car or plane wasn’t moving at a constant rate, but instead speeding up and slowing down. Then, when the flight attendant poured your coffee … look out!

Earth is moving at a fixed rate, and we’re all moving along with it, and that’s why we don’t feel Earth’s spin. If Earth’s spin were suddenly to speed up or slow down, you would definitely feel it.

The constant spin of the Earth had our ancestors pretty confused about the true nature of the cosmos. They noticed that the stars, and the sun and the moon, all appeared to move above the Earth.

Because they couldn’t feel Earth move, they logically interpreted this observation to mean that Earth was stationary and “the heavens” moved above us.

With the notable exception of the early Greek scientist Aristarchus, who first proposed a heliocentric model of the universe hundreds of years B.C.E., the world’s great thinkers upheld the geocentric idea of the cosmos for many centuries.

It wasn’t until the 16th Century that the heliocentric model of Copernicus began to be discussed and understood.

While not without errors, Copernicus’ model eventually convinced the world that Earth spun on its axis beneath the stars … and also moved in orbit around the sun.

Bottom line: Why don’t we feel Earth rotating, or spinning, on its axis? It’s because Earth spins steadily – and moves at a constant rate in orbit around the sun – carrying you as a passenger right along with it.

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Study Reveals Prehistoric Humans Loved Their Dogs

The longstanding belief about human-canine relationships is that the world’s earliest dogs were mere work animals used to hunt game, but it turns out 7,000 to 8,000 years ago, Early Neolithic Siberian foragers had a soft spot for prehistoric Fido.

By analyzing 17 canine burial sites throughout the region, a team of anthropologists was able to determine quite a bit about the relationship between ancient Siberian foragers and their canine companions, which scientists believe looked a lot like large versions of the Siberian Husky.

University of Alberta anthropologist and lead author of the study Robert Losey says dog owners commonly lived near bodies of water, and the Lake Baikal region in modern day Siberia, as well as the areas near the Angara and Lena Rivers, seemed to fit the bill.

By examining sites in these areas, Losey and his team discovered that these Neolithic foragers and their dogs subsisted on the same diet, which included a lot of fish and seal.




“Dog burials appear to be more common in areas where diets were rich in aquatic foods because these same areas also appear to have had the densest human populations and the most cemeteries,” Losey tells Discovery News.

While humans in largely pastoral communities seemed to rarely bury their dogs after death, dogs who lived in hunter-gatherer communities like those in Siberia seemed to share a close and personal connection with their people and were often buried ceremoniously — and not as a celebration of the canine’s hunting skills, evidence suggests.

If the practice of burying dogs was solely related to their importance in procuring terrestrial game, we would expect to see them in the Early Holocene (around 9,000 years ago),” Losey explains.

The level of care with which these dogs were buried — alongside treasured items the dogs likely used everyday, and in some cases alongside their human companions — suggest a special bond must have existed between these ancient peoples and their four-legged friends.

One dog was laid to rest with what looked like a small round stone in his mouth, which the team interpreted to be either some sort of a toy or a special token. Other prehistoric pooches were entombed in death with trinkets like spoons and knives.

Unearthing another site revealed the skeleton of a man who was buried alongside his two dogs, the remains of each dog carefully placed to the left and right of the person.

Maybe the most interesting — and heartwarming, even — burial site contained the ancient remains of a dog whose owner lovingly placed a necklace made of four red deer tooth pendants around the pup’s neck.

A necklace fashioned in the same style as others worn by humans of the time. Perhaps the necklace was the forager’s way of honoring his best friend.

I think the hunter-gatherers here saw some of their dogs as being nearly the same as themselves,” Losey says, “even at a spiritual level.

People came to know them as unique, special individuals,” he adds.

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