Early on, though, something curious happens. From about 0:01.5 seconds to 0:03 seconds (the equivalent of ~75 million years), there is a distinct circular gap in the outer disk of objects. It reminds me of gaps in circumstellar disks made by exoplanets, but as far as I know, the Nice model does not deal with extra planets - and neither does the nebular hypothesis. At least, not in the Solar System.
What's the cause of this gap?
After some thought, I've guessed that these might be the equivalent of the Kirkwood gaps in the present-day asteroid, belt, caused by destructive orbital resonances with Jupiter. These might be due to resonances with Neptune or Uranus - which makes sense, because they immediately disappear once Neptune (at first closer to the Sun than Uranus) interacts with the inner gas giants and begins migrating outwards. However, I'm not sure of my guess.