Wolf volcano erupts on Galapagos island

The Wolf volcano is located on Isabela Island

A volcanic eruption on the Galapagos Islands has raised fears that the ecosystem that inspired Charles Darwin's theory of evolution may be under threat.

On Monday, the Wolf volcano on Isabela Island erupted for the first time in 33 years, spewing fire, smoke and lava.

Experts say the eruption poses no risk to people living on the island.

The island holds the world's only population of pink iguanas but they are not in immediate danger, officials say.

Lava could be seen flowing down the flank of the Wolf volcano

The Galapagos National park said that the lava was flowing in a south-westerly direction.

The iguanas, "which share the habitat with yellow iguanas and giant Chelonoidis becki tortoises, are situated on the north-west flank, which raises hopes that they will not be affected," it said in a statement.

Isabela Island is the largest in the Galapagos archipelago

The volcano lies on the northern tip of Isabela Island, the archipelago's largest.

It is 115km (70 miles) from Puerto Villamil, the only population centre on the island.

The volcano has not erupted for 33 years

"The eruption generated a very large column of smoke that rose more than 10km (six miles) into the air, and later drifted toward the south-west part of the volcano," Sandro Vaca of Ecuador's Geophysics Institute told the AFP news agency.

Pictures taken at night show the volcano illuminated by lava eruptions

The chain of 13 islands and 17 islets, which sits about 1,000km (621 miles) off the coast of Ecuador, is one of the most volcanically active regions in the world.

The Galapagos is a popular destination for tourists wanting to explore its unique ecosystem

There are several varieties of iguanas on the islands.

Unesco has declared the Galapagos a World Heritage Site and has warned the ecosystem is in danger from increased tourism and the introduction of non-native species.

Green turtles and iguanas are just some of the animals which live on the islands

The variety of wildlife on the island famously inspired Charles Darwin to conceive the theory of evolution.

"One general law, leading to the advancement of all organic beings, namely, multiply, vary, let the strongest live and the weakest die," he wrote in On the Origin of Species after visiting the islands.