Ancient Tats

I’ve written before about the increasing number of tattoos you see these days — with reports estimating that about one-third of Americans are sporting ink — and what a cultural change it represents from the United States of my youth. (Arrows and infinity signs are popular these days, by the way.)

It turns out, though, that the current craze for “body art” has a very ancient lineage — and its known history has just gotten even older.

telemmglpict000155855176_trans_nvbqzqnjv4bqmkujzfylr8qfmlqp7nvuva3q8tt5y4yc6db7uimlx80Researchers recently determined that two Egyptian mummies in the British Museum have tattoos.  The mummies are 5,000 years old and date back to pre-dynastic Egypt, which pushes the date of the earliest known use of figurative body art, rather than geometric patterns, back by an additional 1,000 years.  One of the mummies is a woman who has a series of four “s” shapes — perhaps coiled snakes? — inked on her shoulder, which may have been symbols of status, bravery, and magical knowledge.  The other mummy is a man who has depictions of a wild bull and a sheep on his upper arm.  The bull figure was supposed to denote power and virility, but it apparently didn’t help the male mummy, who died of a stab wound to the back when he was between 18 and 21 years old.

The markings were made using a technique that would be considered incredibly crude by modern standards.  The British Museum thinks the tattoos were produced using soot as the coloring agent and needles of copper or bone to insert the soot under the skin.

There’s no way to know, of course, whether figurative tattoos have an even more ancient history, because we don’t have preserved bodies going back 10,000 years.  The discoveries of cave paintings made by the earliest human ancestors, however, suggests to me that the creation of figurative art is instinctive and has played a key role in human development.  It just makes sense that the cave painters would also have experimented with decorating an actual body or two.  I’d bet that if you invented a time machine and went back to check out the humans of 10,000 or 15,000 years ago, you’d see your fair share of ink.



Our Tangled Family Tree

Consider Homo naledi.  A humanoid species whose remains were found several years ago in a cave in South Africa, it had a smaller brain than our direct ancestors, walked upright, and may have used tools.  And, scientists now believe, it lived between 236,000 and 335,000 years ago — which means it would have been alive and kicking when early humans were, too.

mm8345_20150306_134-3The dating of the remains of Homo naledi suggests that the family tree of human beings is a lot more tangled than people once thought.  As scientists focus more and more on searching for fossil evidence of human-like species, they are uncovering new information that reveals a number of different species romping around the pre-historic world.  The Smithsonian page on human ancestry now shows more than 15 early human species.  With so many variations of humanoids, there are bound to be evolutionary dead ends — and, the more human-like remains that are found, the more likely it is that the different offshoots of the evolutionary tree overlapped in time and may have interacted.

Scientists already believe that, around 300,000 or so years ago — or about the same time as the dates suggested for Homo naledi — there were three different offshoots of one of the root humanoid ancestors, Homo heidelbergensis.  Humans remained in Africa, Neanderthals ventured from Africa into Europe, and Denisovans moved east, into Asia.  We know that, for many years thereafter, there was physical interaction between human ancestors and Neanderthals, because many modern humans have a small percentage of Neanderthal DNA.  With three groups of humanoids around, it’s not much of a stretch to imagine Homo naledi existing in that same time frame.   And who knows whether scientists will unearth evidence of other distinct, humanoid species that also date from that same time period?

The intriguing question is:  what happened to those other species?  Did the human ancestors simply prove to be superior in brainpower, body design, tool-making ability, and other attributes that gave them an evolutionary advantage and allowed them to simply out-compete the other species for food, living space, and other conditions that made humans more successful in reproducing . . . or did the early humans slaughter those who were different and drive them into extinction?  Maybe there is a reason that the remains of Homo naledi were found in a cave — they were desperately hiding from our ancestors.

Hairless And Sweaty

At some point in the past, humans and great apes had a common ancestor.  The homo sapiens branch of the tree then veered off in one direction and evolved into the humans of today — largely hairless, especially in comparison with other primates, except on the head and in the nether regions — whereas the great apes remained heavily furred.

What caused the humans to take the smooth-skinned route?  The BBC has an interesting article that attempts to answer that question.  It’s not an easy question, because having a mat of fur seems to have lots of evolutionary advantages.  It protects the skin, is warmer, provides some protection against bites, and may even have a camouflage effect.  So why did the most successful primate in the history of the planet, the one that reached the top of the food chain, ditch the fur at some point in the distant past in favor of the bald look?

The theory is that the evolutionary forces began to work when our early ancestors moved out of the shadowy forests and into the savannah.  By getting out of the shade, the proto-humans moved to a setting that offered more hunting targets, more meat, and thus more protein, which would help them to develop bigger brains.  But, the savannah also featured more heat.  The heavily hirsute creatures who tried the veldt quickly became overheated and had to retreat to the cool forest, where they were left to snack on grub, worms, insects and fruit.  Our less furry ancestors were better able to adapt to the heat, and those who had more sweat glands and could sweat away the body heat were even more capable of running after and killing protein-packed prey in the hot African sunshine.  The standard forces of evolution — time, survival, and procreation — then combined to shift human bodies increasingly away from shaggy fur and toward sweaty hairlessness.  The end product was the modern human, which is both hairless and also the sweatiest primate alive.

Sweaty and hairless.  It’s almost as if evolution was trying to design a creature that could survive August in the Midwest!  Now if evolution would only answer another crucial question:  why do men who reach the AARP membership age seem to lose all of the hair on their legs?

Puppies Of The Permafrost

In the far northeast region of Russia, in an area called Yakutia, portions of the permafrost are melting.  From time to time, the melt exposes the tusks of long-dead wooly mammoths, which are prized by collectors, so local hunters regularly prowl the melt zone, looking for trophies they can sell.

information_items_3462Instead, five years ago the hunters found . . . a puppy, still locked in the ice but apparently perfectly preserved.

When the hunters made the find they alerted scientists who flew to the area and found another frozen puppy from the same litter nearby.  The puppies date back 12,460 years, to the last Ice Age.  The remains of the two puppies have now been extracted from the permafrost and are being studied by excited researchers.  Because the puppies apparently were killed by a mudslide and then immediately encapsulated in the oncoming ice, all of their soft tissue — brains, internal organs, fur, and skin — has been preserved, which is exceptionally rare.  Even parasites on the puppies’ bodies were frozen in place and are being studied.  (It makes you wonder how quickly the ice was advancing, doesn’t it?)

Because the puppies were found close to some butchered and burned mammoth bones, suggestive of the presence of early humans, scientists are very curious as to whether the pups were simply part of a wolfpack in the area, or were part of a wolf-like but separate species that already was allied with early humans and later developed into fully domesticated dogs.  The research on the remains of the two puppies will undoubtedly help in the broad ongoing effort to unravel where the modern dog came from.

It’s pretty amazing to see the body of a mammal so perfectly preserved from a time long before the pharoahs and the building of the Sphinx, when mammoths and saber-toothed tigers still roamed the planet.  It makes you wonder what other remains might be locked in the permafrost, waiting to be exposed in the gradual melt.  Could there be a perfectly preserved Neanderthal or one of those mysterious Denisovans who could teach us a lot about the dawn of humans?

Species-Saving Sex

Don’t look now, but the history of homo sapiens — and of human-like creatures on planet Earth — is getting progressively weirder and more titillating.

article-2029559-0d8dcb7300000578-310_1024x615_largeScientists conducting studies of human genes are learning lots of interesting information about the development of our species.  One of the more provocative findings is that our genetic information indicates that there were multiple instances of significant homo sapien interbreeding with other human-like species — specifically, the Neanderthals, and a mysterious, largely unknown species called the Denisovans —  that left indelible marks in the DNA of modern humans.  And it also appears that the cross-breeding provided us with some useful genetic material, including genes that enhanced the operation of the human immune system and helped our ancestors fight off pathogens.

Not much is known about human history before the dawn of civilization.  Most of what we understand comes from looking at fossils of human ancestors and attempting to piece together the gnarled branches of the human family tree.  Human genetic analysis provides a different kind of window to the past of our species.  It’s now obvious that the early days of the human species saw our ancestors competing with — and apparently having lots of sex with — other hominid species.  We couldn’t have been too much different from them, because the genome evidence means that when humans had sex with Neanderthals and those enigmatic Denisovans, their one-night stands produced pregnancies and non-sterile offspring that, in turn, shared their genes through mating.  All of that cross-breeding among different species helped to make humans what they are today.

We might never learn what happened to the Neanderthals, or the enigmatic Denisovans, and why they died out while humans survived and became the dominant species on the planet.  What we can now say with some confidence is that human ancestors apparently were as interested in sex as modern humans are, and weren’t particularly troubled about who — or what species — they were having sex with, either.

Punch-Outs At The Dawn Of Humanity

The male human face evolved to be able to take a punch.  That’s the intriguing conclusion of a recent scientific study — one that raises some curious additional questions.

The study examined how facial bones respond to impacts and determined which bones are most likely to be fractured in a fistfight.  It then looked at the bone structures in the skulls of our distant ancestors and saw that the same bones were the ones that showed the most development in terms of sturdiness and thickness.  Those also are the bones where there is the greatest difference between the male and female skulls.  The scientists then put two and two together and concluded that natural selection was at work and was preferring the male proto-humans that could best absorb a right cross to the chops.

This theory, if correct, tells us a lot about early humans.  First, under Darwinian theory natural selection operates in response to prevalent conditions, not the occasional unusual circumstance.  That suggests that early human males were brawling constantly, rather than having a dust-up once in a while.  Instead of the human apes using an animal bone while Also Sprach Zarathustra welled in the background in the opening scene of 2001:  A Space Odyssey, think of them squaring off and trading left uppercuts, like participants in a melee during a professional wrestling match or British soccer hooligans.

Second, evolution works only if the trait being selected against doesn’t continue in the genetic pool.  This means that our brittle-skulled ancestors didn’t just shake off a knockout blow and go home to procreate with the missus — they were killed outright.  Whether they were beaten until their skulls cracked like eggshells or just knocked out and left to be devoured by sabertoothed tigers (or hungry members of other tribes), they were cut off from further contributing to the human evolutionary tree.  We flabby modern humans survived to sit in front of our computer screens because our male forebears were tough, thick-skulled, strong-jawed types who didn’t go down at the first blow.

Science is interesting.

Our Extraordinarily Ancient Artistic Impulse

Using dating techniques that examine the build-up of calcium carbonate, scientists have concluded that artwork found in caves in Spain is more than 40,000 years old.  That makes the particular artistic statement — a red dot, found on a wall that features a series of depictions of hands rimmed by red paint — is more than 4,000 years older than the previous oldest known piece of human art.

The age of the art is extraordinary, because it stretches back to the dawn of human immigration into Europe, which is believed to have occurred about 41,000 years ago.  To give some context to the amazing age of the paintings, consider that the first known civilizations didn’t begin until about 6000 years ago, and that if you went back in time 4000 years from today you’d be at a point centuries before the birth of King Tut.

Discoveries like this make you wonder how old human expression truly is, and when it first was displayed.  Is cave painting the earliest form of human artistic expression, or is another form even older?  When did humans first sing, or dance around the fire pit, or create some form of music?  How soon after language was developed did the first poet or storyteller come into being?

The days of these early humans were consumed by hunting dangerous animals, foraging for food, building fires, creating tools and clothing, and avoiding predators — and yet they spent time creating art on the walls of their cave shelters.  The fact that the artistic impulse is found in such early humans says something very powerful about creativity and the artistic urge as a fundamental part of human nature.