“They have it wrong,” Klein said in a telephone interview. “This paper
does not belong in print.”
Klein is a proponent of a competing theory that attributes the
development of modern human behavior to a genetic change to human
brains 50,000 years ago.
“These behaviors appear to have been part of a package that
significantly enhanced human fitness -- the ability to survive and
reproduce,” Klein wrote in a study that was published last year in the
journal Evolutionary Anthropology. “It is in this sense that they
signal true evolutionary change as opposed to mere historical
change.”
Ancient Art, Music Flowered as Communities, Not Brains, Grew
By Ryan Flinn
June 4 (Bloomberg) -- An explosion of art, music, jewelry and hunting
technology appeared 45,000 years ago because of increased population
density, rather than the evolution of the human brain, a study said.
Researchers used genetic estimates of ancient population sizes,
archaeological artifacts and computer simulations of social learning.
They found complex skills involving abstract thinking would be passed
down through generations and across groups only when populations reach
a critical level, according to the study in tomorrow’s edition of the
journal Science.
Increased interaction between groups, the sharing of ideas and the
exchange of raw materials that led to the flowering of human culture
may explain why concentrated centers of industry, such as California’s
Silicon Valley, produce technological innovations, said Mark Thomas,
44, a senior author of the study and a senior lecturer at University
College London in England.
“People learn from their parents or teachers in their group, and this
model demonstrates you have to have a critical number of people
learning to develop complexity,” Adam Powell, 28, a co-author of the
study and a doctoral student at the London university. “The actual
invention of all these technologies was probably very common, but was
only passed on as density increased.”
45,000 Years Ago
Anatomically, modern humans have been around for an estimated 200,000
years, yet scientists have found the first widespread evidence of
sustained symbolic behavior and abstract thinking emerged about 45,000
years ago. The findings include musical instruments, body decoration
with shell beads and tattoos, bows and arrows and microlithic stone
blades, according to the study.
An ancient example of figurative art was discovered recently in a
German cave, depicting a woman with enlarged breasts and genitals,
Powell said. One of the oldest of its kind, it dates back 35,000 years
ago, according to a May 14 study published in the journal Nature.
Powell said his study may explain why modern human behavior appeared
to emerge in different regions of the world at different times.
Evidence was seen sporadically as far back as 90,000 years ago in sub-
Saharan Africa, with a more sustained pattern 40,000 years ago, and in
Europe and western Asia 45,000 years ago. Archaeological samples
indicating similar skills were found in eastern and southern Asia and
Australia 30,000 years ago. Population densities would have reached a
critical point in sub-Saharan Africa and Europe at about the same time
periods, according to the study.
Popular Illustrations
The impetus for human development has been pondered throughout
history, Thomas said in an interview. The 1968 film, movie “2001: A
Space Odyssey,” illustrated the mystery with a scene of a symbolic
monolith slab on an ancient landscape that enabled humanlike apes to
make tools and think critically.
“In reality, what I suspect is these technologies were being invented
all the time, but they never hung on for more than a few generations.
You need sustained evidence for it to be visible in archaeological
record.”
Not everyone is convinced the demographic model caused the behavioral
change. Richard Klein, an anthropology and biology professor at
Stanford University, said the study is flawed because the examples it
cites of human behavior prior to 50,000 years ago are either misdated
artifacts or are open to interpretation as to their level of
advancement.
Competing Theory
“They have it wrong,” Klein said in a telephone interview. “This paper
does not belong in print.”
Klein is a proponent of a competing theory that attributes the
development of modern human behavior to a genetic change to human
brains 50,000 years ago.
“These behaviors appear to have been part of a package that
significantly enhanced human fitness -- the ability to survive and
reproduce,” Klein wrote in a study that was published last year in the
journal Evolutionary Anthropology. “It is in this sense that they
signal true evolutionary change as opposed to mere historical
change.”
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