Marcos Rodríguez Pantoja's life changed forever one day in 1965. That was the day he was torn from his home and forced to live among strange and dangerous animals: human beings. Marcos was 19 years old, but he'd been living in a cave near the Sierra Morena mountains in Spain with a pack of wolves for the past 12 years. As you can probably imagine, it wasn't good luck that led him to those circumstances. Marcos' mother died when he was a very young boy, and when he was about 6 or 7, his father sold him to an aging goatherd. The old man died shortly afterward, and Marcos decided to seek shelter in the mountains instead of returning to his abusive blood relatives.

The story of Marcos' time in the wilderness is nothing short of remarkable. The goatherd had taught him how to make traps to catch rabbits and partridges, which helped keep him alive in the early days. He also looked to animals for guidance. "Whatever they ate, I ate," he told the BBC in 2013, "The wild boars ate tubers buried under the soil. They found them because they smelled them. When they were digging the soil looking for them, I threw a stone at them — they would run away and then I would steal the tubers."

Soon he found his way to the cave that would eventually become his home. He was delighted to find a litter of wolf puppies there, which he says he played with until he fell asleep. But once their mother came home, she nearly chased him off. By the end of the day, however, she was willing to share a portion of her kill with her strange new cub. He had found a new family. In fact, like Mowgli, he became a part of an entire community of animals, including a snake he befriended with milk, and wild goats he learned to get milk from. And that's how he lived until the Guardia Civil discovered him and removed him by force to the village of Fuencaliente.

Imagine you're 19, and you've just been served your first bowl of soup ever. How would you respond? Marcos did what seemed natural — he cupped his hands, dipped them in, then shattered the bowl when he scalded his skin. Nobody had warned him of the danger the hot liquid presented, and it set the tone for much of his life in human society.

Now in his 70s, Marcos has found his own community of human beings, but he still finds himself bewildered and disoriented by the sights and sounds of the city. Even worse, he's often been taken advantage of by unscrupulous types. Perhaps it's no surprise that he told the Spanish newspaper El Pais that he'd found human life to be a disappointment. Still, it's not entirely bad. Now that he is an older man, he's found a place fighting for the planet with environmental groups like Amig@s de Arbores, and in the classroom where he tells children about his unbelievable life story.