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If I told you once, I told you a million times:
It’s The Horses Pulling, Not The Wagon PushingI.
Lasting Evolutionary Change Takes About One Million Years
“The exact cause of these long-term, persistent evolutionary changes is not certain.”
Getting Inside the Mind (and Up the Nose) of Our Ancient Ancestors
“"This is the first real evidence for the steps that led to the evolutionary origin of jawed vertebrates.”
by dovhenis on March 24, 2011
Nov 12 2009 (http://www.the-scientist.com/community/posts/list/220/122.page)
A. From "Aping the Stone Age"
Chimp chasers join artifact extractors to probe the roots of stone tools:
Converging lines of evidence indicate that wild chimps indeed invent distinctive types of tools within communities, and these tools get passed from one generation to the next as a kind of cultural legacy.
For roughly 50,000 generations, Oldowan toolmaking techniques got passed from hominid experts to novices. In recent experiments, it was found that captive chimps display a similar capacity for learning how to use tools by observing more experienced comrades.
One of the projects combines chimp, hominid and modern human data to explore the enduring mystery of why most people are right-handed. Judging by stone tools, by at least 120,000 years ago right-handedness frequently occurred among Neandertals, and archaeological record from ancient Homo sapiens that lived during the same time as Neandertals shows similar signs of a right-handed skew. Most Oldowan toolmakers from nearly 2 million years ago were probably right-handed. However, whereas wild chimp communities display a variety of hand preferences, a trend of relatively stronger right- and left-handedness does appear in chimp groups that regularly use tools, such as nut-cracking stones or sticks for poking into termite mounds to remove the edible insects.
Researchers suspect that "specific genes contribute to human hand preferences". Uomini hypothesizes that people and chimps share a genetic propensity to use one hand more than another on tasks that demand dexterity. Genes for right-handedness, though, have evolved in humans alone, she proposes.
B. Adnauseam, it is culture that drives genetic changes, NOT genetics that drives cultural changes
"Specific genes contribute to human hand preferences"? Read this above abstract again and again. Note: First comes culture. Genetics follows culture. Genes propagate in an expression conformation that maintains their evolved energy constraint level. If/when their higher stratum take-off organism attains an enhanced level of energy constraint the genes modify their expressions accordingly. This is the drive and direction of life's evolution. This is how the horses are harnessed, to the front of the wagon, not to the rear.
C. And also adnauseam, right-handedness is NOT an enduring mystery
Just as life's chirality was the best energy-constraining product of the early organisms, direct sun-energy fueled independent RNA genes, and therefore it was selected to survive, so a preferred-tools-handedness proved energetically advantageous, and since it happened to start with right-handedness it has been since then inducing genetic expression adjustment. And since humans, and even primates, are just fresh young novel organisms on Earth, the process is still going on, not yet completed. Just wait and see. When you return to Earth one-two million years from now you'll hardly find any left-handed people.
(Comments From The 22nd Century)