The team of scientists patiently excavating a complete mammoth skull found on Santa Rosa Island in 2014 lifted the dirt away from its two remarkably well-preserved tusks this week and found them each to be unique: One is coiled, as in an older mammal, and the other is shorter and sloped, as is more typical of a juvenile. The size of the skull is also unusual: Belonging to either a young Columbian mammoth or a mammoth of intermediate size, it is too large for a pygmy mammoth, an extinct species unique to the Santa Barbara Channel Islands. Carbon dating of the stream bank in which the skull was embedded dates it to 13,000 BP (Before Present), the same time period attributed to the island’s Arlington Man, the name given to the oldest human skeletal remains found in North America.
As it eroded out of the stream bank, the fossilized set of mammoth bones — nicknamed “Larry” after Peter Larramendy, the National Park Service biologist who first saw the ivory sticking out of a canyon wall, and also Larry Agenbroad, the noted mammoth paleontologist who researched the Channel Islands and died in 2014 — has been jacketed with burlap and plaster to preserve it by the science team: National Park Service archaeologist Don Morris, paleontologist Justin Wilkins from The Mammoth Site in South Dakota, and preparator Monica Bugbee.
“This mammoth find is extremely rare and of high scientific importance. It appears to have been on the Channel Islands at the nearly same time as humans,” Wilkins said. “I have seen a lot of mammoth skulls, and this is one of the best preserved I have ever seen.”
Measurements of the number, spacing, and thickness of enamel plates of the creature’s teeth may allow the scientists to get within two years of the mammoth’s age at the time it died. The tooth measurements may also identify the species more clearly. Geologists believe mammoths made it to the Channel Islands during a glacial period about 150,000 years ago and during an ice age about 20,000 years ago when the sea level dropped about 300 feet and the four northern islands were linked as one. Isolated on the islands when the oceans rose, the animals became smaller over time, dropping from 14 feet to about six feet in height. The pygmy, or dwarf, mammoth — Mammuthus exilis — probably existed on the islands for about 60,000 years before going extinct around 10,000 years ago, as did many large mammals for reasons as yet unknown.
Once the fossil remains are fully excavated, they will be taken to the Santa Barbara Museum of Natural History for preservation and future display. The museum is also home to Arlington Man, whose bones were discovered by the museum’s curator of anthropology and paleontology in 1959, Phil C. Orr.
On Thursday, October 6, Dr. Daniel Muhs will speak on the new discoveries and research on mammoth arrivals at Channel Islands National Park. The free talk takes place at 7 p.m. in Ventura, at the park’s Visitor Center, 1901 Spinnaker Drive. Find it online live at http://www.nps.gov/chis/planyourvisit/live-programs.htm.