by Alex Rinfret-A stone spear point found in July in a Moresby Island cave may be the oldest evidence of human presence yet uncovered on the northwest coast of America, says archeologist Daryl Fedje.
A team of researchers spent about 10 days in July working inside the huge limestone cave, which extends more than a kilometre underground. The cave was first investigated three years ago, and it continues to reveal tantalizing clues about what animals lived on the Charlottes around the time of the last ice age, and when humans first occupied this area.
They've found skeletons and bones from bears, caribou, birds, fish, bats and mice. The oldest animal bones date to around 17,000 calendar years ago, Dr. Fedje said.
Then this year, in the last hour of their last day at the site, the spear point was found - the first proof of human presence in the area. The point was found in sediments and near bones that have been dated to between 10,400 to 10,600 years old, Dr. Fedje said, although more analysis will be done in the next few months to further pinpoint its age.
The spear tip is similar in style to artifacts found in Gwaii Haanas which are about 9,000 years old, he added.
Researchers believe that the point ended up in the cave after a speared animal crawled inside and died, rather than from humans living inside the cave.
"It's not a pleasant place," Dr. Fedje said. "The temperature is eight degrees all the time and humidity is 100 percent."
It's also pitch black inside the cave system. Researchers worked with small helmet lights which illuminated only small sections of the cave. Dr. Fedje showed slides taken inside K-1, and explained that the darkness was so thorough that he would hold up the camera with no idea what he was aiming at, and shoot random flash pictures.
One of the pictures showed a red-suited team member squeezing through a particularly tight passage known as the "birth canal".
After the birth canal, the cave system opens up into a large chamber about 10 metres by 20 metres, and about 10 metres high. This is where one of the bear skeletons was found.
Dr. Fedje said that Tim Heaton, a professor from the University of South Dakota who was part of the team exploring K-1, believes that some of bones are from grizzly bears, while others are from black bears. Dr. Heaton has been studying bear bones found in similar limestone caves in southeastern Alaska.
One of the bones is the jaw of a very large grizzly bear - the largest Dr. Heaton has ever seen in 10 years of studying bear bones, Dr. Fedje said.
The grizzly bear bones are much larger than the black bear bones, Dr. Fedje said. DNA analysis is expected to provide more information about what type of bear they are from. The find is surprising because grizzlies do not exist on the Charlottes today.
The research team also spent several days exploring a limestone cave in Gwaii Haanas, called Gaadu Din. This cave only extends 40 to 50 metres before being blocked by debris, Dr. Fedje said.
However, researchers did uncover many animal bones inside: black bear, possible grizzly bear, bird, fish, a carnivore canine, and salmon. The salmon bones are particularly interesting, Dr. Fedje said, because the cave is not located near the ocean and the bones must have been brought there. The salmon has an intact back bones and doesn't look like it was digested by an animal, he said, which could point to possible human presence. Charcoal was also found at the site, another possible indicator of human presence.
"That story is yet to be developed, whether people were involved here," he said. "It's going to take a while to figure it out."
The exact location of the caves are being kept secret. Dr. Fedje said there is concern that amateur cavers could destroy the delicate limestone features, or the archeological treasures inside. The caves are also extremely dangerous, he said.
The finds from K-1 and Gaadu Din are giving researchers more information about the extent of the ice age and whether parts of the islands were refugia - ice-free areas where animals and possibly humans thrived. Finding the bear bones has made it difficult to believe that the Charlottes were completely covered by ice, Dr. Fedje said.
"It makes sense there was some refugium here," he said.
The age of the oldest bear bones found so far - 17,000 calendar years - is within what many people believe is the last ice period, he said.
"It's really important, I think, for the refugium issue," he said. "This is going to help potentially answer that question."
The existence of these early bears also shows that the environment was suitable for humans at this time, Dr. Fedje said.
"It is quite important because there is a controversy... about the origin of the people in the New World," he said. One theory is that people travelled south between two huge ice sheets about 12,000 years ago. But new theories point to earlier existence of people, particularly on the west coast.
"The west coast appears to have been ice free earlier than thought," he said. "This is getting a lot of people thinking about the coast."
Dr. Fedje returned to Victoria Friday (Aug. 15). He'll be following up on his finds from the islands over the next few months, and expects to be back again next summer for further cave investigations.