SkunkyArt | Loopydave — How fast is your spaceship? Dr Who

The cybernetic Borg assimilate species in similar fashion to the Cybermen and also use a similar catchphrase ("You will be assimilated"). Likewise, the warrior race of Klingons share similarities with the Sontarans and Draconians .

The Trill also possess the ability to pass on a symbiont after a host body dies, allowing them to effectively live on after death, not entirely dissimilar from regeneration . When joined with a symbiont, the personality of the new host will change as it becomes an amalgamation of their own, plus those of their predecessors, as well as retaining all of their memories. Through specific rituals, it is also possible for the current hosts to interact with their predecessors, as seen in the Deep Space Nine episodes "Facets " and "Field of Fire ", which were DS9 equivalents of multi-Doctor episodes. The ability of Trill to take on the memories and experiences of others was also utilised when Terry Farrell and her character of Jadzia Dax was replaced by Nicole de Boer 's Ezri Dax , in much the same way Doctor actors are replaced when they choose to leave the series.

Like the Silurians , the dinosaur-descended Voth are a sentient, humanoid reptile species that evolved on Earth and developed a technologically advanced civilization. Like those Silurians who built the ship in Dinosaurs on a Spaceship , the Voth left the planet, eventually settling in the Milky Way Galaxy's Delta Quadrant.