Although Destiny 2 takes place immediately after the events of its predecessor, making up less than eight years in the franchise as a whole, the universe built by Bungie is billions of years old. Humanity has a short history compared to other alien races in Destiny 2, with the Hive being one of the oldest species in the universe as creatures evolved from the Krill, who were otherwise destined to live for less-than 10 years. There are beings who are seemingly older than the universe itself, such as The Gardener and The Winnower, whose so-called «flower game» was what created the universe and later allowed the Vex to emerge.
The Traveler's origins are unknown in Destiny 2, but it did bless several races prior to making its stand on Earth and blessing humanity with the Light. There's a difference between the gift of the Light and the Traveler's blessing, however, and this can be seen through the tales of the Eliksni (commonly referred to as Fallen), the Ammonites, the Harmony, and the Ahamkara. These species were all touched by the Light to some extent, whereas humanity and now the Hive have been blessed by the Traveler's Light to receive powers and Ghosts for resurrection.
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The Ammonites were an advanced species who evolved on one of the moons of Fundament, where the Krill also lived. At some point, the Ammonites started worshipping the Traveler after its arrival, and with it, they started worshipping its disciple, the Leviathan. The Ammonites managed to prosper and to create paracausal technology, making them a powerful force in the pre-Destiny 2 eras, but they were eventually wiped out by the Hive's campaign of conquest and destruction, and the Leviathan fell presumably to
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