Evolution

Chimp      HabilisFace      Habilis2      OldowanTools

Earliest Tool-makers -- Still chimp-like, this larger-brained ape makes the first stone tools




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A Godless Philosophy - Contents

Preface  (What's this all about?)

The Story of Evolution

14,000,000,000 y.a. -- The Big Bang
Evolution begins

4,600,000,000 y.a. -- Our Sun and Earth
Stars evolve, producing the complex elements of organic life

2,500,000,000 y.a. -- First life forms on Earth
A bacteria reproduces itself, and the race is on

220,000,000 y.a. -- First mammals
A tiny shrew survives among the dinosaurs

30,000,000 y.a. -- The great apes of Africa
Chimps achieve sociability, planned combat, and use of natural objects as tools

5,000,000 y.a. -- Earliest human ancestors
It looks like a chimp but walks upright

3,000,000 y.a. -- Earliest toolmakers
Still chimp-like, this larger-brained ape makes the first stone tools

1,800,000 y.a. -- Later pre-humans
More human-looking without fur, this naked ape conquers fire and reaches Eurasia   

300,000 y.a. -- Neanderthals
Evolved in Europe's Ice Age, they hunt and kill 7-ton mammoths

50,000 y.a. -- Modern humans (Homo sapiens)
Fully human now, we narrowly escape extinction to follow our destiny

45,000 y.a. -- Spread of modern humans throughout Eurasia
Out of Africa, we encounter the pre-humans and fight our way north

30,000 y.a. -- Extinction of the last pre-humans
Neanderthals, the tough guys, hold out the longest

15,000 y.a. -- First settlements, city-states and empires
It takes us 35,000 years to create the first small city

600 y.a. -- Racial differences and European conquests
Guns, germs and steel

Now -- Human evolution in modern times
Where are we, and what lies ahead?

Theory or Science?  Sources and References


Evolution's Implications  (Summary)


Miscellaneous Musings



Many people accept that evolution is a proven fact, but they can't fully assimilate the idea of chimps becoming people. It's too much of a jump, just too weird.

So with that in mind, let's think about this particular evolutionary step: from a chimp walking upright, to a pre-human animal making tools. What enabled this step was a jump in brain size from 350-400cc. to 600-700cc.

That's a major jump. But consider that it took two million years. How long is that? Long enough for the continents of America and Africa, which drift apart just 3 inches/year, to separate by 94 miles. Long enough for one hundred thousand generations of pre-humans to live and die. The 300cc. jump in brain size we're considering amounted to barely three one-thousandths of a cubic centimeter per generation.

Actually, it's a wonder that greater changes didn't occur during this vast time span -- a testament to the amazing stability and self-correcting capabilities of genetic codes. But evolution has infinite patience, and like water dripping on a stone, will ultimately sculpt the stone.

The increase in brain size which occurred in this evolutionary step was accompanied by a change in hand structure, a fully opposable thumb which provided near-human hand dexterity. So this pre-human still looked like an upright chimp, but it was able to roughly shape stone tools for specific purposes, such as cutters and choppers for butchering and scrapers for cleaning hides.

Anthropologists call this species "Habilis" (meaning "Handy-man"). Its tools were primitive and hand-held, but they were designed with forethought and, in a crude sense, manufactured. Thus began a uniquely human capability that grew through the ages, ultimately leading to Apollo 7 and nuclear weapons.

Meanwhile, hostility between tribes or clans was a more or less constant fact of life. Extreme aggressiveness has been locked into our lineage over thousands of generations, rewarded by the reproductive advantage gained by the successful warrior and his male kin. This has held true not just during the time of Habilis, but for all the millions of years of human evolution before and since.

As far as we know, Habilis never attained control of fire, but its growing brain accelerated human evolution, leading to more successful pre-human lineages, described next.

(Note: after Habilis and before Neanderthals, who arose nearly two million years later, Anthropologists have identified a confusion of lineages: Homo Ergaster, Homo Erectus, Homo Floresiensis, Homo Heidelbergensis, etc. The anthropologists would object, but to make this more accessible to a non-scientist, I will lump all of these lineages under the simple term "later pre-humans.")


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Copyright © 2011 Marshall C. Whitfield