Editor's Note
Editor's Note: Reprinted with permission of the author, Chris Saunders, Communications Specialist, Thomas Jefferson School of Law in San Diego. This article is a compilation of stories written by Mr. Saunders and published on the TJSL website after the initial discovery of the fossils on February 3, 2009. This article was edited by Patrick Meyer, Associate Library Director, Thomas Jefferson School of Law, San Diego.
Fossill Discoveries at New Thomas Jefferson School of Law Building Site
Construction crews have found the tusk, skull and other bones of a 500,000 year old mammoth while excavating the construction site of the new downtown Thomas Jefferson School of Law campus, at 11th and Island Avenues in the East Village of San Diego. "It is the first mammoth skull ever found in San Diego County," said Tom Demere, the Curator of the Department of Paleontology at the San Diego Natural History Museum.
The 8-foot tusk of the mammoth is largely intact and was unearthed when it was struck by the blade of a backhoe during excavation, at a depth of about 20 feet below street level. The paleontologist on scene immediately stopped the digging and experts from the museum were called in to begin the careful unearthing process, which led to the discovery of the skull.
The skull was largely intact and some of its teeth were visible. Parts of one of its legs were also visible. Demere says the bones are in “very good condition.”
“This is an extraordinary event for San Diego County,” said Thomas Jefferson School of Law Dean Rudy Hasl. “It’s an extraordinary piece of history revealed right before your eyes.” Dean Hasl noted that the law school’s namesake, Thomas Jefferson, was fascinated with mammoths and mastodons, “which makes it particularly appropriate that the remains were found on the site of a school which will carry his name forever.”
Tom Demere says the Columbian Mammoth (mammuthus columbi) was the largest North American land mammal of its time and it lived about 500,000 years ago during the ice age. It is related to the modern elephant, though larger, and the one found today is an adult, according to Demere. “It’s a piece of the puzzle in understanding the geological history of San Diego,” Demere says. The Natural History Museum has a contract with the Centre City Development Corporation to manage any fossils recovered on the construction site. The process of carefully digging out all of the remains took several days, and the mammoth will eventually go on display at the museum.
Also found was the partial skeleton of a gray whale (Eschrichtius sp.) including the rostrum, left lower jaw, and left shoulder blade, as well as numerous vertebrae and ribs. The fossil bones occur over an area measuring approximately 15 feet wide by 30 feet long. The distribution suggests the skeleton probably decomposed on the ancient sea floor before being scattered by currents. This fossil is the only record of a Pleistocene marine mammal known from San Diego County and provides evidence that gray whales lived off our coast in the distant past. The geologic age of the specimen is not precisely known, but is between 200,000 and 500,000 years old. The whale fossil was discovered in a sandstone layer approximately 10 feet below a different sandstone layer in which the mammoth was buried. Preliminary analysis suggests that the fossil whale may be at least 100,000 years older than the mammoth.
Gray whales are a rather distinctive group of baleen whales that are known to undergo long, annual, coastal migrations from their summer feeding grounds in the north Pacific to their breeding and nursery sites in Baja California. The fossil record of gray whales is very incomplete, which makes the new specimen discovered at the project site so important. Future studies of the TJSL gray whale will provide new information to better understand the evolutionary history of this truly unique California native.
Finally, the remains of what is believed to be an ancient sloth were found on Friday March 6th. According to paleontologist Pat Sena, who made the sloth discovery, the bones are "poorly preserved" and may not be collectible. Sena adds that this is a very rare find, and that the animal may have stood 6-8 feet tall and measured 10-12 feet in length.
Though a species of sloth exists named after Thomas Jefferson - Megalonyx jeffersonii - it is too soon to tell whether this sloth was one of them. If it does turn out to be Megalonyx jeffersonii, who would be surprised at this point?
The new 8-story ultramodern law school is scheduled to open during the 2010-2011 academic year.
Here’s a link to the video of the fossil discoveries:
http://www.sddt.com/files/media/view7.cfm?media=ISBPOA35
