BY RICHARD GILBERT - Paleontologists have removed a fossilized mammoth tusk from an apartment construction site in Seattle, Washington.
“We are fortunate to have world-class paleontologists in our own backyard,” added Scott Koppelman, senior vice president of AMLI Residential in a press release.
“Although the excavation will cause us some construction delay, the scientific and educational benefits of this discovery clearly outweigh the costs. AMLI is pleased to be working with the Burke Museum.”
AMLI Residential halted construction at an apartment development site in the Cascade neighborhood of South Lake Union for the removal of a fossilized mammoth tusk.
It was discovered during an excavation on Feb. 11.
Burke Museum paleontologists, led by Christian Sidor, worked with the construction crew through the night on Feb. 13 to prepare for the removal of the tusk.
“The AMLI Residential team’s construction crew has been extremely helpful throughout the removal process,” said Sidor, curator of vertebrate paleontology at the Burke Museum of Natural History and Culture.
“It has been a pleasure working with them, and we greatly appreciate their enthusiasm in sharing this important prehistoric find with the Seattle community and researchers by bringing it to the Burke Museum for further analysis.”
The tusk is 8.5 feet long, which is the largest and most complete mammoth tusk found in Seattle to-date.
AMLI carefully removed dirt from around the tusk with shovels, trowels, and brushes.
It was found in wet conditions and is water logged.
As a result, it will require careful long-term conservation at the museum.
Paleontologists placed layers of plaster-soaked burlap bandages on one side of the tusk.
The plaster will help protect the tusk when it is moved from the site.
They ran out of plaster at 10 p.m., but a local Home Depot opened their doors after hours and donated 100 pounds of plaster to help complete the process.
AMLI halted construction again on Feb. 14 so the tusk could be removed and transported to the museum for examination.
The tusk was moved onto a pallet and then a crane lifted the pallet and tusk out of the site’s 30-foot-deep pit.
At the museum, paleontologists will slowly remove the plaster and repair any damage to the tusk, during the drying process.
This will take at least 12 months.
This particular tusk is an important find, not only because of its completeness, but because of its stratigraphic context.
The excavation at the site revealed a “marker horizon,” which is a blue-black layer that has a relatively well-understood age.
The fossil was located about two meters below this layer, so paleontologists estimate the tusk is at least 20,000 years old.
Carbon dating the specimen would provide a definitive age.
The tusk presents a rare opportunity for paleontologists and other researchers to understand the paleoenvironmental conditions present in Seattle during the ice age.
Sediment was collected every 10 centimeters, and will be part of a long-term project to help reconstruct what the environment was like during the time of the mammoth and afterward.
Scientists will wash and prepare the soil to look for small organisms such as insects, snails, seeds, and pollen.
Conditions were much colder and drier than today, and the region was probably covered with grassland and occasional pine trees, similar to the northern edges of modern boreal forests.
Mammoths are ancient elephant relatives that once inhabited the ice-free lands of North America.
They arrived in North America from Asia about 2 million years ago.
Columbian Mammoths grew to 12 feet at the shoulder, which is about the size of the modern Asian elephant.
Their very long tusks curved down from the face and then upward at the ends. These mammoths were herbivores, with a diet that included grasses and conifers.
They chewed grass with large, flat, washboard-like teeth that are very similar to the teeth of modern elephants. They became extinct as the glaciers receded at the end of the Ice Ages, between 10,000 and 11,000 years ago.