Lonesome George, the last of a subspecies of giant tortoises from Ecuador’s Galapagos Islands was found dead Sunday morning by Fausto Llerena, the national park ranger who looked after him.

Discovered in 1972, George was the last of the Pinta Island giant tortoise subspecies, also known as the species Chelonoidis nigra abingdoni. Though his exact age was unknown, scientists say George was over 100. Galapagos tortoises have been known to live to be 200 years old.

In a statement, the Galapagos National Park stated the ranger responsible for looking after George found his body motionless. The tortoise’s body was discovered stretched out leaning toward his watering hole. After checking for any signs of life, the park pronounced George dead.

In order to keep his kind alive, various closely related mates were partnered with George since 1993 by using molecular genetic techniques. After 15 years, two females of a different subspecies managed to lay eggs, but all turned out to be infertile.

Two former UT students of Dr. David Hillis, now both professors of biology at the University of Mississippi, closely followed the life of Lonesome George. Dr. Ryan Garrick and Dr. Beckie Symula worked closely with Dr. Gisella Caccone of Yale University, who has devoted more than 20 years of research to the conservation on the Galapagos tortoises, before accepting positions at Ole Miss.

“Lonesome George was the last individual of his species,” the professors said in a joint statement. “So he was considered the rarest animal on Earth. Park staff also attempted to mate him with a third female of another species, but unfortunately, George showed little interest in these females.”

Scientists said they expected George to live another few decades. An autopsy has been planned to see exactly how the now-extinct species died.

“Lonesome George was an icon for the plight of endangered species because the situation for him was so dire, with only a single living individual remaining. Obviously, the goal of conservation biology is to preserve species diversity, so increasing the numbers of Lonesome George’s species was critical,” the biology professors said.

The Galapagos giant tortoises were famous for helping Charles Darwin formulate his theory of evolution after a visit in the 1830s. Around that time, the tortoises were roaming the islands in large numbers, but the introduction of wild goats and hunting by sailors forced the super-sized animals to the brink of extinction.

“It is extremely sad to see the loss of an entire species in our lifetime, especially when the extinction can be attributed to human behavior,” Garrick and Symula said. “However, Lonesome George is not the only tortoise species that faces extinction. His death highlights the urgency with which we need to continue to act to conserve these others.”

Park officials said there are talks about plans to preserve George’s body for future generations. It seems that the life of the iconic tortoise will live forever.

“The plight of Lonesome George provided a catalyst for an extraordinary effort by the government of Ecuador to restore not only tortoise populations throughout the archipelago but also improve the status of other endangered and threatened species,” the Galapagos National Park said in their statement.

Garrick and Symula have nothing but praise for how the Galapagos National Park and Charles Darwin Foundation have dealt with the situation at hand, calling it “heroic.”

“I think, despite the untimely death of George, this conservation program has been an example of how conservation biology should be done,” Symula said. “Rather than changing how endangered species are handled in the future, the approaches used with George should be a model for future conservation efforts.”