Jane Hastings was a former circus trapeze artist and animal trainer, who traveled to the Congo to work on a movie as a stunt double. There she met Kuba, leader of the local natives, who recognized her as the granddaughter of Jann, a young woman who had once lived there many years before, and who had become beloved of the locals for helping them in times of need. Jane admitted that her grandmother had told her of this, and had taught both her mother and herself all about the jungle. She was surprised, however, to find that the natives remembered Jann, and to find that she herself felt strangely at home there. Soon after Jane had to save the movie workers from danger and afterward decided to remain in the jungle and make it her home, adopting the name her grandmother had been known by as her own.
In the alternate time line of Earth 9904 Jann the Jungle Girl helped Marvel Boy locate the Gorilla Man (Kenneth Hale), who was needed to help FBI agent Jimmy Woo fight a plot of the Yellow Claw's. Immortus has since wiped out the time line of the 1950's Avengers, meaning that these events have no longer happened.