Atalanta was human member of the nyssiros tribe. She was left as a orphan in the wild junge as their parents were killed. Then she was alone in the jungle for almost 10 years. She adapted to the wild nature very well and learnt to use her bow masterly. After 10 years the Nyssiors came to Saria. At first she was watching them but then Lykas the Aleph (leader) of the Nyssiros found her and accepted her to his tribe.
When Jason arrived to Saria Lykas gave him Atalanta as his guide in the jungle. Later Jason with help of Hermes found the spirits of her parents and gave the last rites and last oppurtunity to Atalanta to speak to them.
At the end Jason asked her to join them on their journey and she became another argonaut.
When Jason came back to Iolcus with fleece, She was holding up entrance to the villa from incoming Blacktongues.