 Although ceratopsians are generally considered herbivorous , a few paleontologists , such as Darren Naish and Mark Witton , have speculated online that at least some ceratopsians may have been opportunistically omnivorous . 
 Although ceratopsians are generally considered herbivorous , a few paleontologists , such as Darren Naish and Mark Witton , <a href='been_done' title='1'><mark>have</mark></a> speculated online that at least some ceratopsians may have been opportunistically omnivorous . 
Although ceratopsians are generally considered herbivorous , a few paleontologists , such as Darren Naish and Mark Witton , done speculated online dat at least some ceratopsians may have been opportunistically omnivorous .