Jones was fined for his incident with rookie wide receiver Amari Cooper, which Jones has already said he's appealing. His fine was expected, but the same cannot be said of Dunlap. He was fined for unnecessary roughness committed during the Raiders game, even though he was never flagged directly for it.
The NFL confirmed via Pro Football Talk that Dunlap was fined for his role in the Jones/Cooper scuffle.
You can clearly see Dunlap go after Raiders tackle Austin Howard as he's going at it with A.J. Hawk and after Howard took a cheap shot at Jones from behind. Though, Dunlap's shove from behind isn't exactly fair either. Howard also was fined for his role in the altercation.
Jones' fine is for $35,000, partly due to the fact he's had trouble on and off the field in the past. The same isn't true of Dunlap though, as he was fined a mere $8,681 for his infraction.
It seems fair enough, especially since Howard was fined $8,681 for unnecessary roughness as well.