Tag: ancient humans

Do You Have Neanderthal DNA? The Shape of Your Skull May Tell.

A Neanderthal skull (left) has a different shape from a human skull (right)

The shape of your brain may say a lot about the Neanderthal in you.

New research has found that modern humans carrying certain genetic fragments from our closest extinct relatives may have more oblong brains and skulls than other people.

Modern humans possess unique, relatively globular skulls and brains. In contrast, the closest extinct relatives of modern humans, Neanderthals, have the elongated skulls and brains that are typical of most primates.

Previous research had suggested these contrasting skull shapes might reflect differences in the size of various brain regions in modern humans and Neanderthals, and how these brain areas were wired together.

However, brain tissue doesn’t fossilize, so the underlying biology has remained elusive,” co-lead study author Philipp Gunz, a paleoanthropologist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany said.

To help solve this mystery, scientists first took CT scans of seven fossil Neanderthal skulls and 19 modern human skulls. They developed imprints of the interiors of the skulls’ braincases and measured their roundness.

Next, the researchers analyzed nearly 4,500 modern humans for whom they had both genetic data and magnetic resonance imaging (MRI) scans of their brains.




We reasoned that if we could identify specific Neanderthal DNA fragments in a large enough sample of living humans, we would be able to test whether any of these fragments push towards a less globular brain shape, allowing us to zoom in on genes that might be important for this trait,” senior study author Simon Fisher, a neurogeneticist at the Max Planck Institute for Psycholinguistics in Nijmegen, the Netherlands said.

The Neanderthal DNA fragments contained two genes previous research linked to brain development.

One, UBR4, is linked with the generation of neurons, and the other, PHLPP1, is associated with the development of fatty insulation around nerve cells.

The scientists noted that if a person has more Neanderthal DNA than average, that does not necessarily mean their brain is more oblong.

The Neanderthal brain had a different shape from our brains

Two people who have very similar total amounts of Neanderthal DNA — for example, 1 percent of their genomes — may well carry completely different fragments,” Fisher said.

The researchers also noted these skull differences likely did not reflect any differences at the time of an infant’s birth: Modern humans and Neanderthals have similar braincase and skull shapes at that time, Gunz said.

After birth, differences in brain development likely resulted in the pronounced differences that are found in skull shape between adults of the two lineages, he added.

Future research can look for more Neanderthal DNA linked with modern human brains and determine what specific effects these ancient genetic variants might have by growing brain tissue with Neanderthal DNA in the lab, Fisher said.

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Pass it on: New Scientist

A Functional, Beating Hearts Will Soon Be 3D-Printed Using Patients’ Own Cells

Inside a lab that will open in a couple of months in Chicago, a biotech startup will soon begin perfecting the process of 3D-printing human hearts that could eventually be used in transplants.

The process combines several steps that have been developed by various researchers in university labs. First, a patient’s heart will be scanned using an MRI machine to create a digital image of the heart’s shape and size.

Next, doctors will take a blood sample. Using techniques that have been developed over the last decade, the blood cells will be converted into stem cells–and then converted a second time into heart cells.

Those new heart cells will be combined with nutrients in a hydrogel to make a “bio-ink” that can be used in a specialized 3D printer.

Printing one layer at a time, with a biodegradable scaffolding to keep everything in place, the cells can be formed into the exact shape of the patient’s original heart.

The new heart will be moved to a bioreactor to strengthen it. Amazingly, new heart cells outside a body will begin to self-assemble.

When the heart is strong enough, technicians will raise the temperature to melt the scaffolding around the cells.




The new heart can then be transplanted–and because it is the exact size of a patient’s original heart, and made from the patient’s own cells, it has a greater chance of success than a traditional transplant.

In studies, other researchers have successfully transplanted stem cells in both humans and animals without the need for anti-rejection drugs.

Most people who receive heart transplants now don’t live more than a decade. Their body may reject the organ directly.

The drugs they take to suppress their immune system–in an attempt to prevent the body from rejecting the foreign organ–may also make them unable to fight off another disease, such as cancer.

The Biolife4D heart, in contrast, won’t require patients to take immunosuppressant drugs since it is an exact genetic match.

The company isn’t the only startup in the space. A startup called Prellis Biologics, for example, has another printing process that is optimized for speed, and that includes blood vessels.

A company called Organovo already makes 3D printed human tissue for drug discovery. But Biolife4D may be the only startup to use equity crowdfunding.

The company has opened up investment to the public. “We wanted to make [the investment opportunity] available to everybody, not just wealthy people on Wall Street,” Morris says.

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Pass it on: New Scientist

How Do Aliens Solve Climate Change?

The universe does many things. It makes galaxies, comets, black holes, neutron stars, and a whole mess more.

We’ve lately discovered that it makes a great deal of planets, but it’s not clear whether it regularly makes energy-hungry civilizations, nor is it clear whether such civilizations inevitably drive their planets into climate change.

There’s lots of hope riding on our talk about building a sustainable civilization on Earth. But how do we know that’s even possible? Does anyone across the cosmos ever make it?

Remarkably, science has now advanced to point where we can take a first step at answering this question.

I know this because my colleagues and I have just published a first study mapping out possible histories of alien planets, the civilizations they grow, and the climate change that follows.

Our team was made up of astronomers, an earth scientist, and an urban ecologist.




It was only half-jokingly that we thought of our study as a “theoretical archaeology of exo-civilizations.” “Exo-civilizations” are what people really mean when they talk about aliens.

Astronomers refer to the new worlds they’ve discovered as “exoplanets.”

They’re now gearing up to use the James Webb Space Telescope and other instruments to search for life by looking for signs of “exo-biospheres” on those exoplanets.

So if we have exoplanets and exo-biospheres, it’s time to switch out the snicker-inducing word “aliens” for the real focus of our concerns: exo-civilizations.

Of course, we have no direct evidence relating to any exo-civilizations or their histories. What we do have, however, are the laws of planets. Our robot emissaries have already visited most of the worlds in the solar system.

We’ve set up weather stations on Mars, watched the runaway greenhouse effect on Venus, and seen rain cascade across methane lakes on Titan.

From these worlds we learned the generic physics and chemistry that make up what’s called climate.

We can use these laws to predict the global response of any planet to something like an asteroid impact or perhaps the emergence of an energy-hungry industrial civilization.

Science fiction has given us enduring images of alien races. Not surprisingly, most of them look a lot like us but with different kinds of foreheads or ears, or a different number of fingers on their hands.

In developing our first cut at a science of exo-civilizations, my collaborators and I weren’t interested in what aliens might look like or what kind of sex they have.

To do our job we had to avoid the specifics of both their individual biology and their sociology because science provides us little to work with on those fronts. There was, however, one place where biology was up to the task.

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Pass it on: Popular Science