Varro traditionally mated for life. When two Varro had intimate relations, they experienced olan'vora – "the shared heart". This made their body chemistries interdependent, causing withdrawal symptoms if the two people separated. The effect got stronger with each coupling, and prolonged separation from their mate could literally be fatal for a Varro.
In the 1970s, the Varro launched a ship of exploration. As years went by, the ship became generational, and expanded. Originally consisting of one segment, they built more and more, until the generational ship was much larger.
The nature of the generational ship meant that the Varro society developed into a semi-oppressive regime in which contact with other cultures was avoided at all costs and the will of the individual was subservient to the will of the group. This led to the founding of a rebel group within the Varro who introduced silicon-based parasites into the ship's hull to separate the various sections so each could go their own way.
In 2375, the Varro generational ship experienced heavy problems with their warp engines as a result of the virus. Luckily, they came across the Voyager, who gladly offered assistance. After two weeks, the Voyager team discovered the parasites that were eating away at the hulls of both ships. They were able to stabilize the ship long enough to evacuate the affected sections but the generational ship broke up.