Neanderthals’ Mysterious Extinction

Neanderthal DNA reveals 50,000-year-old viruses that could help explain their extinction. In a study of ancient Neanderthal DNA, researchers found traces of 3 viruses that cause colds, cold sores, genital warts, and cancer.

Ancient humans might have been responsible for spreading these bugs, but I don’t think we need to blame only homo erectus, for there were several types of ancient humans around at the same time as Neanderthals.

Most experts think the Neanderthal species went extinct from a variety of causes, including changing climate, low fertility rates and human interactions. As can be seen from illnesses that swept through American Natives after the arrival of European settlers, trying to recover from unfamiliar illnesses introduced by distant cousins wouldn’t have helped. Poor health can have a negative impact on survival.

Not only could these ancient viruses help explain the Neanderthals’ extinction, but they might help us better understand the modern versions that still infect humans today.

About 54,000 years ago, a group of Neanderthals lived in Chagyrskaya Cave in Southern Siberia. Researchers studied the DNA data of two people from the cave to look for 3 viruses: adenovirus, herpesvirus, and papillomamirus. Adenovirus can cause colds and flu, herpesviruses can cause cold sores or genital warts, and some cancers are linked to papillomavirus.

A 2021 study discovered adenovirus in 31,600-year-old human teeth from Siberia. This more-recent study is nearly 50,000 years old. Some experts estimate humans and Neanderthals interbred between 60,000 and 50,000 years ago. Besides DNA, they probably passed around diseases.

A 2016 study suggested that breeding with Neanderthals may have boosted humans’ immunity to previously unknown diseases. But the Neanderthals may have been less lucky. A cold does not have to be fatal to decrease hunting efficiency or other abilities. With an already small population, getting sick might have contributed to Neanderthals’ extinction roughly 40,000 years ago.

 

https://www.msn.com/en-us/health/other/scientists-discovered-50-000-year-old-viruses-in-neanderthal-dna-that-could-help-explain-their-mysterious-extinction/ar-BB1nKNuC?ocid=hpmsn&cvid=f10bd090b2834e28ca31725fb862078f&ei=41

 

Martian Shelter 4

We’re going to look at a different style of shelter this time. Something a little more complicated to build, I suppose, but which could be more... comfy, should we say?

This shelter is underground. Deep underground, not just some sand kicked over it. Building it would take tunnel-boring machines, which are quite heavy. Perhaps these would be shipped before people were sent, along with some robots to use the machines to bore out a network of tunnels and living quarters. Yes, apparently, some people are ready to go back to living in caves.

But ‘underground’ does not need to mean dark and unwelcoming. I watched an episode of a science show on Netflicks a couple weeks back, where the people were digging out a series of tunnels under New York City. They had some complicated equipment on the roof of a warehouse that gathered and concentrated sunlight before it was piped into the tunnels. Yes, I did say concentrated and piped. The tunnels they created were fully lighted, and with smooth, level floors, ceilings and walls, seemed far distant from a creepy cave.

The theory about living in man-made tunnels on Mars is that the gravity is weak and Mars doesn’t have any quakes, so you wouldn’t need as much support to hold up the ceilings; and there ‘probably’ would not be any moisture seepage. But, this plan does call for some heavy-duty insulation. Martian air may be thin, but Martian dirt and rocks are cold! Even without that insulation, the dirt and rocks would keep that nasty radiation out.

Of course, there are some drawbacks to this idea. There always are, right? All that equipment would be expensive to get there. And once it finishes digging out that first small habitat, then what? Oh, if there’s a big influx of immigrants, the equipment could be busy for years or decades, forming a city here, a city there... But eventually, one assumes, it will become obsolete or unneeded. A lot of money to just let rust away.

And it’s possible there’s more water on Mars than we think, so seepage could be a problem. With all the insulation installed to keep the internal temperature agreeable, we might not even know if seepage was occurring. I hear some of you thinking ‘Then it’s not a problem,’ but that’s not necessarily true. There could be some kind of mold, fungus or other organism that could start growing, possibly leading to health problems for our colonists. Water flows, and ice can expand and create cracks. This could - over time - undermine (so to speak) our efforts at adequate support.

If you own a house, you know you need to keep an eye open for such things, and if you don’t deal with small problems that crop up, you’ll eventually pay for it with a huge repair bill. But these tunnels would not be for an individual’s use; it sounds more like they would be cities, as least to begin with. Owned by committee, you might say. Would that ‘committee’ have the foresight to watch for and deal with these types of problems while they were small? Or would they be political entities, always kicking the financial can down the road?

Okay, if you don’t like the idea of a cave-dwelling, we’ll keep looking. I’ll see what else I can ‘dig up’ for you to consider.

http://www.imagineeringezine.com/e-zine/mars-makeshelter.html

Cold and Salty

When you and I think of someplace nice to live, we probably aren’t thinking “really cold and super salty”. And yet, there are organisms that do.

After 18 months of gathering cold salty water from remote lakes located in Antarctica - including during the extreme winter - scientists discovered... microbes! One location was Deep Lake, whose water is so salty, it remains unfrozen down to -20°.

At least one strain of microbes contained plasmids, which are small molecules of DNA which can replicate independently in a host cell and often contain useful genes. A plasmid can also grab a piece of DNA from the host cell and incorporate it in itself. They’re certainly complicated, for being so tiny.

Viruses have a protective protein coat that helps them invade unsuspecting cells. Once inside, the virus forces the cell to replicate virus DNA and package it into protein shells, which are pushed out of the ‘nest’ to find their own host cell and repeat the process. Most viruses damage the host cell.

One particular plasmid - called pR1SE - is so much like a virus, the scientists weren’t sure how to classify it. Before this Antarctica discovery, plasmids were known to move from cell to cell when 2 cells were touching, or they wandered around as a piece of naked DNA. However, pR1SE must have thought it too cold in Antarctica to wander around naked, so it had developed a coating of proteins that could attach to a cell wall. Once attached, the protein coat would produce buds (called vesicles), and those buds broke off, taking bits of plasmid DNA to do the same with other cells of the same species.

Virus? Plasmid? This pR1SE version seemed to be something in between. In fact, having discovered this mechanism, scientists are wondering if possibly viruses are ‘more advanced’ versions of plasmids.

Another microbe found in those hypersaline lakes is a ‘cannibal virus’, or virophage, the 3rd virophage ever discovered. This type of virus only infects cells that are already infected with a ‘regular’ virus. As the regular virus uses the cell’s mechanisms to reproduce copies of itself, the virophage inserts its genome into the virus, thus getting the virus to reproduce virophage DNA. The number of copies of the regular virus is greatly reduced, so damage is reduced.

There’s plenty of tiny life in them there super-cold, super-frigid lakes, from things that hardly seem like life (regular plasmids), to something slightly more advanced (pR1SE), through another advancement (viruses) and right to something (virophage) that can try to limit the damage done by the prior version (viruses). Who could have guessed that life in Antarctica would be so complicated?

So, let’s take a lesson from this. Life is complicated. If you are creating a new planet or even just a new continent, try to make the life cycle complicated. I have problems with a planet of sand that produces butterflies and giant worms, and that’s all. If the giant worms only have butterflies to eat, how do they get so big? And what do the butterflies eat?

https://phys.org/news/2017-08-antarctic-salt-loving-microbes-insights-evolution.html

http://www.sciencealert.com/cannibal-viruses-in-antarctica

https://www.newscientist.com/article/2144518-antarctic-mystery-microbe-could-tell-us-where-viruses-came-from/