Friday, January 16, 2009

Pigmy mammoth tusk found on Santa Cruz Island?

Mammoth tuskThe discovery of what appears to be a full mammoth tusk on Santa Cruz Island has excited scientists and may offer a glimpse of California beach life during prehistoric times.

Scientists believe 14-foot-tall mammoths swam out to the Channel Islands from the mainland nearly 20,000 years ago, possibly lured by the sweet smell of island grassland for grazing. Later stranded by rising sea levels, the animals shrank over time to a dwarf version.If the find is confirmed, researchers hope it will yield further clues about the evolution and eventual extinction of the pony-sized pygmy mammoths.

Scientists have unearthed mammoth remains at dozens of sites on San Miguel and Santa Rosa islands. But such finds are much rarer on Santa Cruz, where the animals would have struggled to negotiate the steep peaks and find sufficient grass to feed on amid the rugged terrain.

"This is the most substantial and significant find of mammoth remains on Santa Cruz Island," said Lotus Vermeer, who heads the Nature Conservancy's Santa Cruz Island project. "These kinds of finds are exciting because they add pieces to the puzzle, which helps to enlighten us on our past." ...

If the finding is confirmed, scientists will want to determine the age of the remains using radiocarbon dating. Previous finds suggest that humans may have arrived while mammoths still roamed the islands, raising the possibility that the animals were wiped out through hunting. The earliest human remains found on the islands date back about 13,000 years, while the most recent mammoth skeleton dates from about 12,800 years ago, Vermeer said.

... Gill showed the pictures to the country's leading mammoth expert, Larry Agenbroad, director of the Mammoth Site of Hot Springs in South Dakota. Agenbroad told the Nature Conservancy that the partially embedded remains appeared to include a mammoth tusk, several ribs and possibly a femur, Vermeer said. Agenbroad was not available for comment Wednesday.

Another researcher, who reviewed three of the photographs, disputed that analysis. Paul Collins, curator of vertebrate zoology at the Santa Barbara Museum of Natural History, said what looks like a tusk has features that are more consistent with a fossilized jawbone from an extinct species of whale. He added that the type of solidified sandstone in which the remains were found often contains marine remains.

via Possible mammoth tusk found on Santa Cruz Island - Los Angeles Times.

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