The Zox symbiote was born on Trill in 2221 and was joined with its first host, Yerel, in 2239. A talented Starfleet tactical officer, Yerel Zox served briefly aboard the legendary Constitution-class U.S.S. Enterprise under Captain Christopher Pike. In 2262 he accepted a posting to Starfleet Academy as an instructor in starship targeting systems, where the famed Pavel Chekov was once counted among his students.
Amorea was the second host to be joined with Zox, in 2301. She served in the Federation Science Bureau and worked extensively with Dr. Gillian Taylor of the New Cetacean Institute. In 2310 Amorea Zox participated in an oceanographic survey of the planet Pacifica led by Taylor with the humpback whale Harpo, son of 20th-century transplants George and Gracie.
The symbiote was joined with its third, and current, host in 2393. An accomplished warp theorist, Derve experienced some initial difficulty integrating the memories of Zox's former hosts, but undertaking the zhian'tara rite brought reconciliation and a new direction. The symbiote's affinity for Yerel's adventures in the 23rd century led Derve Zox to join Starfleet, where he now serves with distinction in the Corps of Engineers.