ROANOKE TIMES
Copyright (c) 1996, Roanoke Times
DATE: Friday, September 13, 1996 TAG: 9609130140
SECTION: NATIONAL/INTERNATIONAL PAGE: A-7 EDITION: METRO
DATELINE: WASHINGTON
SOURCE: Associated Press
ARCHAEOLOGISTS have documented a shift in weather patterns, beginning about 5,000 years ago, and nearly simultaneous changes in the way people lived.
The El Nino weather events that can cause so much disruption around the world began occurring about 5,000 years ago, according to a team of researchers who say the shift in climate may help explain cultural changes going on at the same time.
Archaeologists and climate experts studying fossils in Peru report today in the journal Science that fossils indicate the area had a tropical climate with little year-to-year variation until about 5,000 years ago.
Species dated from later periods are those that can adapt to more temperate weather with sometimes sharp changes, reported Daniel Sandweiss of the University of Maine.
Cultural changes began occurring at about the same time, he said.
``I wouldn't want to say that climate drives culture, but certainly changing climate requires adaptation,'' Sandweiss said, noting that ``shortly after 5,000 years ago, Peruvians began to build large temples along the coast.''
Indeed, cultural change at that time is more or less true of much of the early Americas, he said. ``It was a time when cultures began to show greater complexity.''
``The paleontological [fossil] evidence has been sort of murky on this issue'' of when El Nino began. ``People have been looking for answers to this issue for some time,'' commented John Kutzbach of the University of Wisconsin, who was not a member of Sandweiss' team.
The Earth's orbit was somewhat different before 5,000 years ago, said Kutzbach, who has also done El Nino research. But, he added, ``the changes in the Earth's orbit are gradual, so they don't explain a threshold of why, at around 5,000, there would have been a change.''
El Nino is a weather event every few years in which pools of warm Pacific water shift and winds change over the Pacific Ocean, bringing heavy rains to the coast of northern Peru and reducing the available fish in the region.
Sandweiss acknowledged that suggesting a connection between changes in climate and society is ``just speculative.''
But he noted that ``during the period from 8,000 years ago to 5,000 years, people in most of world were settling down in farming villages. Maybe the greater stability of climate ... made that more possible.''
``When this great climate variability entered the system 5,000 years ago, it may have created an opportunity for new solutions for new climatic problems,'' Sandweiss speculated.
For example, he said, ``people who had, or appeared to have, solutions, can acquire power.'' Those who can claim better connections to the gods or at least better recognize the signs of change can become the leaders.
LENGTH: Medium: 58 linesby CNB