Anyone who has spent any time surfing the Internet
has at one time or another seen a picture (cute or otherwise) of a
meerkat suddenly standing up when it hears something. There was a time
in history when this was not the case and some brave or confused meerkat
probably accidentally discovered the maneuver and its benefits. Most
people assume the same thing happened with the first ancient human who
carefully leaned against a tree or cave wall and fell forward while
moving his or her legs in order to stay upright. According to a new
study, this assumption is wrong. A new paper uses geology to propose
that there was a supernova bombing Earth with cosmic energy a few
million years ago that caused constant worldwide lightning strikes which
burned down the forests of trees out ancestors were hanging out in and
forced them to the grassy ground where they learned how to stand and run
from the fires and lightning. Plausible? Could this have caused the
first upright meerkat brigade too?
“The observation is that there’s a lot more charcoal and
soot in the world starting a few million years ago. It’s all over the
place, and nobody has any explanation for why it would have happened all
over the world in different climate zones. This could be an
explanation.”
Professor Adrian L. Melott of the Department of Physics and Astronomy at the University of Kansas co-authored the paper, “From Cosmic Explosions to Terrestrial Fires?” published this week in the Journal of Geology. He explains in a press release
how he and co-author Brian Thomas of the Department of Physics and
Astronomy at Washburn University in Kansas built their theory on some
known facts. For example, it is accepted that a layer of iron-60
deposits lining the world’s sea beds came from a very near supernovae
explosion only about 163 light years away during the overlap of the
Pliocene Epoch and Ice Age. That roughly coincides with the appearance
of Lucy, owner of the earliest bipedal hominin species (Australopithecus afarensis) fossils ever found. Why is the iron-60 significant?
“We contend it would increase the ionization of the lower
atmosphere by 50-fold. Usually, you don’t get lower-atmosphere
ionization because cosmic rays don’t penetrate that far, but the more
energetic ones from supernovae come right down to the surface — so there
would be a lot of electrons being knocked out of the atmosphere.”
Electrons in motion is the cause of lightning bolts, but this 50-fold
increase means there were a LOT of lightning bolts as a result of this
atmospheric ionization and they were striking all around the world,
resulting in massive fires that forced Lucy and her relatives to
jump/climb/fall to the ground. Lucy died from the fall but we’re living
proof that some of her kin didn’t and they eventually got tired of
bloody knees and palms.
“After this conversion to savanna, they would much more
often have to walk from one tree to another across the grassland, and so
they become better at walking upright. They could see over the tops of
grass and watch for predators. It’s thought this conversion to savanna
contributed to bipedalism as it became more and more dominant in human
ancestors.”
This definitely sounds plausible. Unfortunately, it causes modern
humans to wonder if this catastrophic supernova-caused cosmic
bombardment could happen again … perhaps from Betelgeuse, which is only
652 light years from Earth. Fortunately, Melott says that’s not likely.
Unfortunately, he thinks we have bigger things to be concerned with.
“Worry about solar proton events. That’s the danger for
us with our technology — a solar flare that knocks out electrical power.
Just imagine months without electricity.”
Maybe we should learn how to climb trees again?
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