At more than 100 years old, Diego the tortoise will be able to look back on his life and smile (do tortoises smile?) knowing that his species probably wouldn’t be here today if it wasn’t for him.

The centenarian had a pretty important job to do a few decades ago as he was one of three remaining males of his species, the Española tortoise, on the Galapagos Islands.

Tortoise populations around the island were critically low when the Galapagos National Park was created in 1959, with many species on the brink of extinction. Cut to 1971 and the remaining Española tortoises (two males and 12 females) were taken to the Charles Darwin Research Station so that conservationists could spark some captive breeding.

Diego was brought to the island six years later from the San Diego Zoo (I can only assume where he got his name from) and he proved to be quite the ladies’ man.

Incredibly, the tortoise pretty much saved his species as he’s credited with creating up to 800 progenies. A follow-up genetic study found that Diego is the father of nearly 40 percent of the offspring that were released into the wild on the island.

Despite Diego’s valiant efforts, his species isn’t out the woods just yet.

Washington Tapia, a tortoise preservation specialist at the Galapagos National Park, told the Daily Mail: “I wouldn’t say [the species] is in perfect health, because historical records show there probably used to be more than 5,000 tortoises on the island.

“But it’s a population that’s in pretty good shape – and growing, which is the most important.

Out of the 15 species of giant tortoise known to have originated in the Galapagos, three have gone extinct

All hope for another threatened species, Chelonoidis abingdoni, faded when its last known survivor died in 2012 at more than 100-years-old. Sadly, the tortoise was called Lonesome George on account of him being the last of his entire species.

Have you ever thought about what it would be like to be the last human on earth? Yeah, pretty depressing.

He was considered the rarest creature on the planet when he was alive and highlighted the work that conservationists were doing on the Galapagos. Researchers tried their best to get him to mate with the remaining females, but even when he did, the eggs became inviable.

It’s thought Lonesome George died of a cardiac arrest and he was found dead by Fausto Llerana, who looked after him for 40 years.

Featured Image Credit: San Diego Zoo