Complex sentence: Carnosauria has traditionally been used as a dumping ground for all large theropods, but analysis in the 1980s and 1990s revealed that other than size, the group shared very few characteristics, making it polyphyletic.
Split into simpler sentences: Carnosauria has traditionally been used as a dumping ground for all large theropods. However, analysis in the 1980s and 1990s revealed that other than size, the group shared very few characteristics, making it polyphyletic.