Vanishing Statues

A tiny island sits in the middle of the Pacific Ocean. It’s extremely remote—the islanders’ nearest human neighbors are 1,300 miles (2,090 kilometers) away! Locals call the place Rapa Nui (RAH-puh NOO-ee). It’s also known as Easter Island. But the islanders aren’t alone out there. Nearly 1,000 giant stone figures called moai (MOH-eye) silently guard this distant land.

The people who settled the island about 800 years ago, also called Rapa Nui, carved the moai to honor their ancestors. They were a group of Polynesians, the Indigenous people of the islands in the central and southern Pacific. “The moai represent generations that have come before,” says Terry Hunt. He is a scientist who has studied Rapa Nui for 25 years.

“The people in Rapa Nui today still feel very strongly about the moai,” he says. But unfortunately, these powerful symbols of the past are at risk of disappearing.

A tiny island sits in the middle of the Pacific Ocean. It’s very remote. The islanders’ nearest human neighbors are 1,300 miles (2,090 kilometers) away! Locals call the place Rapa Nui (RAH-puh NOO-ee). It’s also known as Easter Island. But the islanders aren’t alone out there. There are also 1,000 giant stone statues called moai (MOH-eye). They silently guard this land.

People settled the island about 800 years ago. They carved the moai to honor their ancestors. They were Polynesians. They’re the Indigenous people of the islands in the central and southern Pacific Ocean. “The moai represent generations that have come before,” says Terry Hunt. He is a scientist. He’s studied the people and island for 25 years. “The people in Rapa Nui today still feel very strongly about the moai,” he says. But sadly, these powerful symbols of the past are at risk.

Most moai stand about 13 feet (4 meters) tall and weigh as much as seven cars. The largest ever completed reaches 33 feet (10 meters) high. Each clan, or family group, on Rapa Nui had its own statue, which stoneworkers carved out of blocks of soft volcanic rock called tuff. (See “Parts of a Moai”)

After finishing the massive moai, the Rapa Nui moved them miles across the island using ropes and human power. Workers placed many statues on the coast, facing the family they were meant to watch over. The Rapa Nui believed moai brought them “protection, wisdom, and strength,” Hunt says.

Most moai stand about 13 feet (4 meters) tall. They can weigh as much as seven cars. The largest one reaches 33 feet (10 meters) high. The people of Rapa Nui lived in family clans. Each family group had its own statue. Stoneworkers carved them out of blocks of soft volcanic rock called tuff. (See “Parts of a Moai.”)

They moved the finished moai miles across the island. They used ropes and human power. Workers placed many statues on the coast. They faced the family they were meant to watch over. They thought moai brought them “protection, wisdom, and strength,” Hunt says.

Now protecting the statues themselves is the challenge.

“What made each statue easy to carve also makes it vulnerable to weathering,” says Hunt. (See “Vocab Lab”) Because of its softness, tuff was easy to carve using simple stone tools. But it is also porous. Rain and salty ocean air can seep into its holes. Salt crystals grow inside the rock and push outward, slowly cracking it apart from within.

“It happens so slowly that we don’t see it,” says Hunt, “but it’s happening all the time.”

Making things worse, about 70 percent of moai have lichen (LIE-kuhn) on their surface. These fuzzy colonies of algae and fungi slowly eat away at the stone, softening it to a clay-like texture. Plus, thousands of cattle and horses on the island rub against the statues, wearing away their edges and carved features.

Some weathering and erosion of the statues is expected over time, but climate change is making things worse at a much faster rate. Warming temperatures are causing sea levels to rise and storms to become stronger and more frequent. That’s a big problem because many moai sit along the coast.

“We’ve seen storm surf hit the platforms and wash over the carvings,” says Hunt. “Seawater on moai is not good for them at all.”

Now protecting the statues is a challenge. “What made each statue easy to carve also makes it vulnerable to weathering,” says Hunt. (See “Vocab Lab.”) Tuff’s softness made it easy to carve using simple stone tools. But it is also porous. Rain and salty ocean air can seep into its holes. Salt crystals grow inside the rock and push outward. That slowly cracks the stone apart. “It happens so slowly that we don’t see it,” says Hunt. “But it’s happening all the time.”

About 70 percent of moai have lichens (LIE-kuhns) on their surface. These fuzzy colonies of algae and fungi are making things worse. They slowly eat away at the stone and cause it to soften. Plus, there are thousands of cattle and horses on the island. They rub against the statues. That wears away their edges and carved features.

Some weathering and erosion of the statues happens over time. But it’s happening much faster than expected. That’s because of climate change. Warming temperatures are causing sea levels to rise. Storms are becoming stronger and happening more often. That’s a big problem because many moai sit along the coast. “We’ve seen storm surf hit the platforms and wash over the carvings,” says Hunt. “Seawater on moai is not good for them at all.”

Scientists and local communities have teamed up to try to protect the statues. Researchers are using drones and smartphones to create detailed 3-D models of these treasured symbols. This allows them to study the moai and track erosion without touching them.

They’re also testing chemical treatments to keep moisture out of the stone—but with caution. “These carvings are irreplaceable,” Hunt says. “You don’t want to do anything that might harm them.”

For the people of Rapa Nui, the moai are much more than statues. The moai are part of who they are. If these stone giants disappear, a piece of treasured human history could vanish too.

Scientists and local people have teamed up. They’re trying to protect the statues. Researchers are using drones and smartphones. They make detailed 3-D models of the statues. This lets scientists study and track the moai’s erosion without touching them.

They’re also testing chemicals that keep water out of the stone. But they must use caution. “These carvings are irreplaceable,” Hunt says. “You don’t want to do anything that might harm them.” The moai are much more than statues to the people of Rapa Nui. The moai are part of who they are. A piece of treasured human history could be lost if these stone giants disappear.