NEW findings! did something go Bezerk on earth?! Study: Neanderthals died out 42,000 years ago as Earth’s magnetic poles flipped!!

We find that geomagnetic field minima ~42 ka, in combination with Grand Solar Minima, caused substantial changes in atmospheric ozone concentration and circulation, driving synchronous global climate shifts that caused major environmental changes, extinction events, and transformations in the archaeological record.

[link to science.sciencemag.org (secure)]

Earth saw a lot of commotion when its magnetic poles flipped 42,000 years ago.

Scientists have known about the flip since the late 1960s. Earth's magnetic poles aren't static - they're generated by electric currents from the planet's liquid outer core, which is constantly in motion. As of late, Earth's magnetic North pole has wandered considerably on a path toward northern Russia.

But for the most part, scientists didn't think the last pole flip had a major environmental impact. Sure, the planet's magnetic field got weaker, allowing more cosmic rays to penetrate the atmosphere, but plant and animal life wasn't known to have been greatly affected.

A new study now suggests a more dramatic phenomenon occurred: The additional cosmic rays may have depleted ozone concentrations, opening the floodgates for more ultraviolet radiation in the atmosphere. Shifting weather patterns may have expanded the ice sheet over North America and dried out Australia, prompting the extinction of many large mammal species. A solar storm, meanwhile, might have driven ancient humans to seek shelter in caves.

As competition for resources grew, our closest extinct human relative, Neanderthals, may have died out.

"It would have been an incredibly scary time, almost like the end of days," Chris Turney, an Earth scientist at the University of New South Wales, said in a video describing the new research.

[link to news.yahoo.com (secure)]

There are other hypotheses.

The Neanderthals had survived a LOT of climate changes including the various ice ages and the eruption of Toba which plunged the Earth into a muli-year winter of darkness.

However, I think the answer to what happened to the Neanderthals and later, the megafauna, was US.

Neanderthals were incredibly strong but their arms and hands were not very good for throwing projectiles such as spears. There is evidence they were night hunters with superior vision who would approach and attack prey at close range.

Humans have arms and hands that are very good at throwing. There is evidence that they had atlatls and perhaps bows as long as 50,000 years ago.

Plus, they could outrun any Neanderthal.

So, like any competing top predators, they fought.

If the Neanderthals were night hunters who slept in the daytime, the humans would simply attack the Neanderthal caves during the day. They could strike with atlatl darts or arrows from a distance and run away as needed from the slower rivals.

Like many primitive tribes we have encountered, hunting and warfare were a major part of their culture.

As to the Neanderthal DNA that we now carry, it is more likely that humans took female captives and raped them. That is exactly what we see in primitive societies and even today.

BTW, atlatls would be ideal for hunting mammoths and other megafauna. A hunting party could launch a shower of darts on a group of mammoths from a safe distance up to 100 yards. Badly wounded animals would be tracked and finished.

Note that fleet and smaller game such as deer would NOT be so vulnerable to such hunting tactics. Those species survived.