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Thursday, February 12, 2015

THE ORIGIN OF HUMANITY


Who are we?  There are two primary points of view: 


  • Scientific:  only 19% of Americans feel that humans evolved, ala Darwin, a percentage that has, actually, doubled over the past 30 years.
A global survey indicates that "we" don't think much of evolution:


While 80% of Europe tend to believe that human beings developed from earlier species of animals, only 40% of those in the USA think so, which is higher than the 25% of Turkey.  Muslim countries generally are similar or lower than Turkey in this belief, but only 8% of Egyptians and 11% of Malaysians accept Darwin's Theory of Evolution.

All that said, I will nevertheless here provide the scientific point of view, reporting on my finally completing a book written by Donald Johanson on Lucy's Legacy, which I began reading six years ago.  Lucy was found by Johanson in 1974 in Ethiopia, got her name because a tape of Lucy in the Sky with Diamonds was repeatedly being played in the camp during the analysis.

Here are a few interesting facts about our origins, mostly from that book:
  • At one time Lucy, 3.2 million years old, was accepted as our missing link.  Certainly, she looks a lot more ape than human (this is just some graphic enhancement from her partial skeleton).

  • In 2009, Ardi, 4.4 millions old, was found, also in Ethiopia.  She is now taken to be the symbolic link from ape to human.

  • While the chimpanzee is said to be our closet relative, I've long felt that the bonobo (right), which acts like us, as our most likely link. Both are 98.7% identical to human genes, but are of different species.  I was astonished when I first saw one at the Stuttgart Zoo, where this interesting animal sat in a chair, folded his arms and stared at me.  Hominoids split off from the two about 4-7 million years ago, where Ardis looks a lot more bonobo-like than any chimpanzee.  Females dominate in bonobo clans and missionary position sex is the dominant control factor, not war or fights, which prevail in the chimpanzee society.
  • In those few million years of evolution, Homo sapiens evolved from the 400 cubic centimeters of brain material in Lucy to around 1350 cc today.  Your brain consumes up to 25% the energy used by your body.
  • Spinning off from Lucy (Australopithecus afarensis), almost 2 million years ago, some hominids, perhaps Homo habilis and/or Homo egaster, ventured out of Africa into Europe and Asia.  Then, Homo heidelbergensis (right) left Africa around 350,000 years ago, branching into Homo neanderthalensis (250,000 years ago) and Homo sapiens (130,000-200,000 years ago).  Neanderthals actually had bigger brains than humans, but went extinct 40,000 years ago.  These transitions are amorphous, for it is said that H. sapiens also journeyed away from Africa around 65,000 years ago.  Paleoanthropologists continually debate these topics and keep changing their estimates.  But that is the nature of science, even astrophysics.  In any case, us hominoids have been hunting and gathering for 99% of our existence.  Our recent development has been exponential and incredible, considering how long we just wandered about and barely survived.
  • Mind you, our predecessors had spears and stuff almost half a million years ago, and Homo erectus could well have controlled fire around this timeframe, but H. sapiens, us, probably evolved in Africa from a mythical mitochondrial Eve 200,000 years ago.
  • There was a 100,000 year long ice age which began 240,000 years ago, so that by the year 140,000, the human population reached a critical low. Interestingly enough, while I have raised fears that The Venus Syndrome caused by marine methane could spike atmospheric temperatures, it is possible that,  historically, this gas could well have warmed the globe and saved Humanity.
  • In the South African coastline, cooking of mussels probably occurred 164,000 years ago, and sophisticated tools, necklaces, and bracelets have been analyzed to be 75,000 years old.  The higher temperatures in central Africa and the affect of warming ocean currents around south Africa helped Humanity survive.  The southern Cape might well have been the original Garden of Eden.
  • The Earth again cooled around 73,000 years ago, most likely caused by the eruption of Mount Toba in Indonesia, said to be 100 times greater than any recorded volcanic activity, resulting in, perhaps, only 1,000 breeding pairs surviving in Africa and southern India.   Mind you, this is just pure guesswork, and there are naysayers.  In any case, Mount Toba is now Lake Toba.
  • So let us take a flying leap and enter "modern" history, when farming, was invented 10,000-12,000 years ago. Wheels (potter's) and recorded history came along around the same time, maybe 5500 years ago in Mesopotamia, although Egypt is also noted for inventing writing.  the father of history is Herodotus (Greece), around 2500 years ago.  Chinese history only became evident a little more than 2000 years ago during the Han Dynasty.  I keep interjecting, here the awesome size of just our Milky Way Galaxy, where light would take 100,000 years to cross from one end to the other.  And there are 250 billion galaxies just in the observable sky!  While this time/space comparison can make us so insignificant, we could well be the only semi-intelligent life in the entire Universe, an issue that has regularly been addressed in the past.
  • Which brings us to today.  But what of the future?  Are we so superior that Homo sapiens will eventually spread across the Universe?  First, it is reported that 7% of our human genes are undergoing rapid evolution.  There is lighter skin in Eurasia and a loss of lactase-tolerant genes in Africa and Asia. While a lot of scientific mumbo jumbo can be found in the literature on our inability to drink milk, it could have merely been because those who could in the past died from sour milk, leaving alive the ones who couldn't tolerate this drink.  While human populations are growing in size (4 inches over the past 150 years, mostly because of better nutrition), isn't it more sensible for us to get smaller to conserve resources?  
  • The matter of singularity, intelligence and control might argue for robots or cyborgs replacing hominoids.  Certainly, machines are better suited for long-range space travel, and computers already can beat our best chess players.  Maybe Homo sapiens are destined to become the final biological link to Humanity and "life" into the next billion years.

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