It could be that they're not related at all and I just like hearing double time, but I think I've heard the term DnB before, but I've never had it properly defined. Thanks!
These are all fast breakbeat rhythms. Drum and bass music is generally broken beats (as in not 4-to-the-floor) in 160-200 bpm tempo range with emphasis on drum and bass elements. There are a lot of subgenres with specific nuances.
I would say the first beat is jungle, the second is drum'n'bass and the third some kind of breakbeat. They are all kind of similar. I found this video that might explain it better than me.