Los Angeles’te kuzey – güney doğrultusunda uzanan ünlü La Brea Bulvarı’nında bulunan La Brea Katran Çukurları’na (La Brea Tar Pits) oldukça yakın bir noktada yeni bir fosil yatağı bulunuyor. Keşfedilen fosiller arasında bir aslana ait kafatası, kılıç dişli kedi kalıntıları, kurt, bizon, at ve neredeyse hiç bozulmamış bir mamut iskeleti bulunuyor.
Araştırmacılar, katran çukurlarının yanında bulunan bir otoparkın altında 2006 yılından bu yana 16 fosil yatağı buldu, kazı çalışmaları ise geçtiğimiz yılın yaz aylarında başlamıştı. La Brea’da kurulmuş olan Page Müzesi yetkilileri, bulunan fosillerin müzenin Buzul Çağı koleksiyonuna eklenebileceğini belirtiyor. Bu keşif, müzenin mevcut envarterinin iki katına çıkmasını sağlayacak.
700 farklı türden fosillerin keşfedildiği Proje 23 olarak adlandırılan araştırma sırasında bulunan dev mamut fosiline “Zed” adını veren araştırmacılardan Shelley Cox, Zed’in neden önemli olduğunu şöyle açıklıyor, “Zed’i önemli kılan onun tam bir örnek olması. La Brea’da ortaya çıkardığımız fosillerin hepsinden daha büyük, dişleri de tam ve şimdiye kadar bulduklarımızın hepsinden önemli derecede büyük, Zed’in kemiklerini inceleyen araştırmacılar, kemiklerden anladıkları kadarıyla hayvanın 47-49 yaş aralığında bulunduğunu” ifade ediyor. Bulunan fosil, karbon hesabına göre 38 bin ile 42 bin yıl öncesinde yaşadığı belirtiliyor.
La Brea Katran Çukurları bölgesi 10 bin ve 40 bin yıl öncesi aralığında yer alan zaman diliminde birçok hayvana evsahipliği yaptı. Dünyanın en ünlü arkeolojik bölgelerinden biri olan bölgede yer alan yapışkan zift, yıllar boyunca mamutlar, mastodonlar, kılıç dişli kediler ve diğer Buzul Çağı hayvanlarını yutarak dünyanın en büyük fosil yataklarından birini oluşturdu.
Exposed left acetabulum of Zed’s pelvis. The fossil is from the first complete individual mammoth to have been found in Rancho La Brea. (Credit: Photo courtesy of the Natural History Museum of Los Angeles County)
http://jonmcculloch.com/?svil=strategia-treding-con-master-option&cfd=c8 strategia treding con master option Vast Cache Of Ice-age Fossils Uncovered At La Brea Tar Pits In Los Angeles
The Page Museum at the La Brea Tar Pits, part of the Natural History Museum of Los Angeles County family of museums, has announced an endeavor of discovery and research so enormous that it could potentially rewrite the scientific account of the world-famous La Brea Tar Pits and their surrounding area—one of the richest sources of life in the last Ice Age, approximately 40,000 to 10,000 years ago.
Project 23: New Discoveries at Rancho La Brea, undertaken in the heart of urban Los Angeles, has to date uncovered over 700 measured specimens including a large pre-historic American Lion skull, lion bones, dire wolves, saber-toothed cats, juvenile horse and bison, teratorn, coyotes, lynx, and ground sloths. Most rare of all is a well-preserved male Columbian mammoth fossil, about 80% complete, with 10-feet long intact tusks found in an ancient river bed near the other discoveries. This latter fossil is the first complete individual mammoth to have been found in Rancho La Brea. In recognition of the importance of the find, paleontologists at the Page Museum have nicknamed the mammoth “Zed.”
“The name signifies the beginning of a new era of research and discovery,” according to Dr. John Harris, Chief Curator, Page Museum at the La Brea Tar Pits. “Zed is a symbol of the potential of Project 23 to revolutionize our knowledge about this area.”
When Zed was removed from the ground, his fossilized remains were encased, along with their surrounding soil, in plaster “jackets” and taken to the Page Museum. In the Museum’s famous Fish Bowl laboratory paleontologists are carefully excavating the bones from these jackets in public view. Every time a jacket is opened, the fossil is meticulously cleaned and the surrounding matter—soil that is filled with thousands of tiny fossils of plants, fish, snails and other organisms—is removed and carefully studied. As Zed’s parts are prepared, many of them go on view in the Museum. Currently, Zed’s huge tusks are being cleaned and prepared inside the Museum’s Fish Bowl lab.
The Page Museum at the La Brea Tar Pits is famous as one of the world’s largest and most diverse collections of Late Pleistocene fossils—objects so important that the last 300,000 years of the Pleistocene is known to scientists as the Rancholabrean Land Mammal Age. Paleontologists at the Page Museum now estimate that Project 23 could double the collection by three to four million specimens. These finds may inform decades of new research on subjects including global warming, geological change, biodiversity and life cycles.
So that scientists may focus on Project 23: New Discoveries at Rancho La Brea, the Page Museum has temporarily halted excavations at Pit 91, one of the world’s most plentiful urban excavation sites. A public observation area remains in place. As excavations continue, the Natural History Museum of Los Angeles County Family of Museums will develop Project 23-related experiences for the Page Museum’s annual visitors.
“This is an outstanding example of how research, collections and exhibitions come together at the Natural History Museum and its family,” stated Jane G. Pisano, president and director. “Whether conducting basic science or arousing wonder in our visitors, we work across the institution to learn, educate and inspire.”
Uncovering Project 23: New Discoveries at Rancho La Brea
When the neighboring Los Angeles County Museum of Art, LACMA, began construction in and around the parkland, scientists at the Page Museum had the opportunity to survey areas that would otherwise have been inaccessible to them. The subsequent paleontological salvage operation proved to exceed all expectations.
Under the guidance of Page Museum scientists, 23 enormous intact blocks were lifted out of the earth, crated with wooden planks into “tree” boxes, which ranged in size from 5x5x5 feet (weighing 3 tons) to 12x15x10 feet (weighing 56 tons) from the sixteen asphaltic deposits salvaged from the site. Project 23: New Discoveries at Rancho La Brea gets its name from the reference to the number of extracted crates—with each box bearing its own number (1-23) and excavations for the massive new project. In recognition of their expertise, the Page Museum and the Natural History Museum were given ownership of these asphaltic deposits recovered during the course of construction.
Rather than beginning at ground level and digging into the ooze of asphalt or “tar pit” to expose trapped specimens as they’ve done for the last century, Page Museum paleontologists will begin their Project 23 excavations at the top of each earthen block, uncovering fossils buried in a sediment composite of sand and asphalt. In addition to discoveries of mammal fossils, finds to date include turtles, snails, mollusks, abundant tree trunks and complete insect and leaf mats, all of which are expected to provide important environmental data.
Zed the mammoth was not part of the 23-crate finds but was found as an individual specimen in a neighboring area.
The Page Museum at the La Brea Tar Pits and the Natural History Museum of Los Angeles
Originally known as the County Museum of History, Art and Science, and housed in the first dedicated museum building in Los Angeles, the Natural History Museum of Los Angeles County was constructed in 1913 in Exposition Park in part, for the purpose of holding extraordinary finds from excavations conducted in the early 1900s. Soon after the Museum opened to the public, the owners of Rancho La Brea granted the Museum the sole right to excavate their land. (They later deeded the 23 acres of Rancho La Brea to Los Angeles County and donated its abundant fossils to the Museum.) The Natural History Museum’s first aggressive dig, begun in 1913, was the largest excavation undertaken at Rancho La Brea prior to Project 23.
The Page Museum, created as an on-site exhibition and research facility, opened at the tar pits in 1977, at which time the Natural History Museum returned the fossil collection to Rancho La Brea. The Page Museum at the La Brea Tar Pits and the William S. Hart Museum are members of the family of museums headed by the Natural History Museum of Los Angeles County.
In 2010, the Natural History Museum in Exposition Park will reopen its renovated 1913 Building. Among the major exhibits to be unveiled will be the new Age of Mammals Hall featuring skeletons from the Rancho La Brea Collection.
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