Yes, she was a military officer whose duties were split between working on the bridge of the Galactica and as a Viper pilot. She was also Apollo's sister & Adama's daughter.
The only humans we know in this show are the Colonials, who don't know enough about the soft-bodied Cylons to create such a thing and haven't been in this area of space before. The only humans who've been in this area of space before were the ones that went to Earth, but that was a very long time ago and they knew nothing at all about Cylons, and they had no way to know or any reason to care that Cylons, other humans, or anybody else was eventually going to come along to do this to.
The "known" Cylons are accounted for already and wouldn't have done something like this to themselves (unless the internal conflicts begun on Caprica by 6 & 8 have developed into a civil war, which is quite a stretch).
The only group left other than the above also just happens to be the only group that could possibly meet the criteria of knowing the "known" Cylons well enough to design the "biological" weapon against them and predict that they might come along to this area (seeking Earth) to get hit by it. And the fact that they're not even spoken about by the other Cylons implies that the two groups were separated as a result of a pretty intense conflict.
