Here at S8int.com, we can't tell you how to read this article. Our point of view is; never mind the dates--this is another in a series of "discoveries" which tend to indicate-- as Christians believe,-- that man did not evolve from a "primitive" state to a "modern" state. The sophistication of those who lived before us is increasingly evident even to non-believers.
Contact: Philip Lippel
National Science Foundation
ARLINGTON, Va.- Perforated shells found at South Africa's Blombos Cave appear to have been strung as beads about 75,000 years ago-making them 30,000 years older than any previously identified personal ornaments.
Archaeologists excavating the site on the on the coast of the Indian Ocean discovered 41 shells, all with holes and wear marks in similar positions, in a layer of sediment deposited during the Middle Stone Age (MSA).
BLOMBOS CAVE: Click and drag photo to resize. Script from The Java Script Source
"The Blombos Cave beads present absolute evidence for perhaps the earliest storage of information outside the human brain," says Christopher Henshilwood, program director of the Blombos Cave Project and professor at the Centre for Development Studies of the University of Bergen in Norway.
The shells, found in clusters of up to 17 beads, are from a tiny mollusk scavenger, Nassarius kraussianus, which lives in estuaries. They must have been brought to the cave site from the nearest rivers, 20 kilometers east or west on the coast.
The shells appear to have been selected for size and deliberately perforated, suggesting they were made into beads at the site or before transport to the cave.
Traces of red ochre indicate that either the shell beads themselves or the surfaces against which they were worn were coated with this widely used iron oxide pigment.
A few years ago, Blombos excavators found chunks of inscribed ochre and shaped bone tools that challenged the then-dominant theory of behavioral evolution, which held that humans were anatomically modern at least 160,000 years ago but didn't develop critical modern behaviors until some punctuating event 40,000 or 50,000 years ago.
Henshilwood and his colleagues (including Francesco d'Errico and Marian Vanhaeren of the University of Bordeaux, France, and Karen van Niekerk of the University of Bergen) believe the Blombos bone tools and ochre show that modern behavior like the use of external symbols developed gradually throughout the Middle Stone Age, not suddenly when our ancestors spread from Africa to Eurasia. Similar finds at other recently excavated African sites support their belief.
Nassarius shell beads from Blombos Cave, an archaeological site on the South African coast, are 75,000 years old. Credit: C. Henshilwood & F. d'Errico. Click and drag photo to resize.
Some critics have argued that those African artifacts did not represent true symbol use. The newly found beads strengthen Henshilwood's assertion considerably.
According to Henshilwood, "Agreement is widespread that personal ornaments, such as beads, incontrovertibly represent symbolically mediated modern behaviour.
Until now, the oldest beads in Africa date to about 45,000 years. The discovery of 41 shell beads in sand layers at Blombos Cave accurately dated as 75,000 year old provides important new evidence for early symbolically organized behaviour in Africa."
Blombos Cave contains artifacts from both the Middle and Later Stone Ages. The artifact-rich layers are clearly separated by a layer of dune sand deposited about 70,000 years ago.
While LSA strata, which are less than 2000 years old, also contain Nassarius shells, they are a different color from those in the MSA strata.
Also the LSA shell sizes and the placement of the piercing differ from, and are less uniform than, the MSA shells. Sand grains surrounding the MSA artifacts, dated by optically stimulated luminescence, show they were buried-removed from sunlight, which "resets" the dating clock-75,000 years ago.
Burnt lithics, or stone, found nearby in the same strata, were independently dated by thermoluminescent techniques as 77,000 years old. Thousands of individual grains of sand were dated to search for signs of mixing between the Middle and Later Stone Age layers; none was detected.
Henshilwood and coworkers thus conclude that ancient Africans deliberately selected the shells and modified them for use as beads at least 75,000 years ago.
To Henshilwood, this clearly indicates that the cave's early inhabitants used symbols in modern fashion.
"Once symbolically mediated behaviour was adopted by our ancestors it meant communication strategies rapidly shifted," he says, "leading to the transmission of individual and widely shared cultural values - traits that typify our own behaviour."
Excavation of the Blombos site has been funded by the National Science Foundation (US), the South African National Research Foundation, the Center National del la Rechereche Scientifique, the European Science Foundation, The University of Bergen, the Anglo Americans Chairman's Fund and the British Council.
NSF is an independent federal agency that supports fundamental research and education across all fields of science and engineering, with an annual budget of nearly $5.58 billion.
NSF funds reach all 50 states through grants to nearly 2,000 universities and institutions.
Each year, NSF receives about 40,000 competitive requests for funding, and makes about 11,000 new funding awards. NSF also awards over $200 million in professional and service contracts yearly.
MADISON -- Thanks in part to dynamite and the gold-seeking Mexican fishermen who detonated it in the late 1970s, archaeologists have discovered the remains of a 5,000-year-old shell mound.
Constructed of cement-like floors, the mound, researchers say, is the oldest known platform intentionally built in Mesoamerica, the cultural region comprising Mexico, Belize, Honduras, Guatemala and El Salvador, and it could completely change our understanding of the prehistoric people who once inhabited this area.
The mound, built almost entirely from marsh clamshells, is 240 feet long, 90 feet wide and 21 feet tall. John Hodgson, a University of Wisconsin-Madison doctoral degree candidate in anthropology discovered it last October on a remote island in a swampy area along the Pacific coast of Chiapas in Southwestern Mexico.
Hodgson has named the site "Alvarez del Toro," a tribute to the naturalist who studied the fauna and wildlife of this region.
When Hodgson reached the mound after spending two days traveling by car and foot and then cutting through miles of marsh grass nearly twice his height, he immediately saw the floor layers made from shells.
"A trench created by a dynamite explosion about thirty years ago exposed a large number of floor layers formed of clam shells capped with a cement-like material made from burned shell and sand," he explains.
To determine when the mound was constructed and occupied, Hodgson collected six samples of charred wood taken at different floor levels about two feet apart and then used the technique of Carbon-14 dating to ascertain the age of the wood material.
The results show that the mound was used for about 500 years.
"The time differences of the Carbon-14 dates," explains Hodgson, "suggest that the floors of the mound were either resurfaced or the mound was enlarged about every 20 to 30 years."
Based on the analysis, the very top floor layer dates to 2575 B.C. - almost 4,500 years ago. Each level below this layer increases in age with the lowest tested layer dating back more than 5,000 years ago to 3024 B.C.
Hodgson notes that this bottom layer, approximately 12 feet from the top of the mound, is not the base floor layer: "The dynamite crater only exposed the top half of the mound - there are about 10 feet of undisturbed floors underneath where we were able to recover samples for dating." As a result, he says the first construction of the mound could even be several hundred years older.
The mound's age and its floor layers make this site unlike any others previously known for this time period in Mesoamerica, says Hodgson, adding that all other archaeological sites in Chiapas are shell middens - piles of shells and garbage that gradually accumulated from human activities.
"The new site did not form accidentally from trash deposits," he explains. "The people who built it planned on creating a very large raised platform."
Given the durability of the construction, Hodgson suspects that each floor layer of the mound once served as the floor for a wooden building. He plans to return to the site this September to search for holes in the floor layers where posts supporting walls or roofs may have been placed.
The idea that people were living at Alvarez del Toro for long periods of time, however, counters decades of anthropological thinking, says Hodgson. He explains, "The common interpretation for this time period is that people were fairly mobile and often moved to different locations to collect seasonally available food resources."
Additional research, he adds, could provide solid evidence that these people may have been much more stationary than previously thought.
If this proves true, John Clark, an anthropologist at Brigham Young University who collaborates with Hodgson and supports his research, says, "This could be one of the most spectacular findings in our area for many, many years."
Both Hodgson and Clark, interested in understanding the past so they can reconstruct earlier ways of life, say that this evidence of purposeful construction could change what they and their colleagues have thought about the times surrounding important events in the prehistory of Mesoamerica.
"This site looks like the very first steps towards complex society and has the earmarks of what we see later on when people start forming villages," says Clark. "It would suggest that these people might be more sophisticated than we give them credit for. This could reshape a whole set of questions that I've been asking for the last 30 years."