December 20, 2005 Source: University of Lethbridge:
http://www.uleth.ca/notice/display.html?b=4&s=4935 When Hippos Roamed Suffolk U of L Geography Researcher Helps Verify 700,000-year-old Human Occupation of Prominent United Kingdom Archaeology Site A recent and widely-reported discovery that humans occupied parts of what is now the north-east coast of Britain more than 200,000 years earlier than previously thought has a University of Lethbridge connection. Dr. Rene Barendregt, a U of L researcher and Associate Dean of the Faculty of Arts and Science was the only Canadian on a team of archaeologists, paleontologists and technicians who were studying a coastal site called the Comer Forest-bed Formation, located at Pakefield, in Suffolk, United Kingdom. Barendregt’s research specialty is dating sediments and artifacts by measuring their magnetic properties. According to Barendregt, the earth’s magnetic field characteristics (including polarity) change over time, and these changes are well known from records in ocean sediments, cooling lavas, and dust accumulations in the interiors of continents. "The paleomagnetic records of glacial and interglacial deposits on land are less continuous and therefore must be matched with the continuous records found in oceans," Barendregt said. "Once that is done, plant, animal and human remains contained in the land records can be assigned to the global geomagnetic polarity timescale." It was exactly such measurement and correlation work which allowed Barendregt to assign these sediments and artifacts to the last 780,000 yrs. of earth history -- a span of time when the earth’s field is normally magnetized (the north magnetic pole is in the northern hemisphere). "The paleomagnetic data provided a lowermost age while work done by other researchers, using amino acid breakdown in shells associated with the artifacts, provided a limiting upper age (700,000 yrs)," Barendregt said. "Perhaps most importantly, the artifact layer is overlain by strata containing evidence for multiple glaciations and interglaciations- a record that has been well worked out for northern Europe, and again, a record for which the magnetostratigraphy has been developed." Barendregt added that glacial sediments are often difficult to date because they are deposited in sterile (cold) environments and few dating techniques can be applied. Paleomagnetism offers one of the best and most robust methods of dating and correlating strata. This verification, and other methods used to show the age of the artifacts discovered by the team, moved the archaeological timeline back by more than 200,000 years and attracted a massive amount of international media attention to the UK-based researchers. Their findings, with Barendregt’s contributions, were recently published in the international research journal Nature as their cover story for December 15. A copy of the complete research paper (as well as a commentary on the research paper), is available for downloading at the end of this document. Once connected to continental Europe, this site has been well known for more than a century as a source of pre-historic artifacts from the Middle Pleistocene era. Well-known Victorian Geologist Charles Lyell was convinced that sooner or later the Cromer Forest beds would yield evidence of human occupation -- what was not well known was precisely how old they were. The site continues to be a rich source of fossil mammals (including hippos, mammoths, elephants, rhinos, tigers and lions), as well as reptiles, aquatic species and plants -- but is on the edge of the North Sea, so excavations or collections are subject to rapid changes brought about by wave and tidal erosion, longshore drift, and particularly, North Sea storms. Working under these difficult conditions, the team found more than 30 worked flint pieces (which show evidence of being hammered or specifically shaped to produce a tool or weapon) that, by any archaeological standard, is good evidence of human occupation or presence. What the team found in this case was, as one commentator described it, ‘like striking archaeological gold.’ "This particular find is important because it points to humans entering northern Europe earlier than previously thought," Barendregt said. "They made effective use of mild climatic conditions, the presence of plentiful animals for food, and a lower sea level which allowed migration onto the British Isles for the first time. It also points archaeologists to more northern localities and older deposits, as they search for the earliest patterns of human migration." Barendregt hopes to return to England next summer together with other workers, in an attempt to further unravel the details of ice age history and human migration in an area that has already produced tantalizing evidence. -- 30 --
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