Complex sentence: Some of their most significant evidence has been initially found in Texas, but they might have been present worldwide: another key region for gigantopterid fossils is in China, and the consolidation of all major continents into Pangea would have allowed for easy global dispersal.
Split into simpler sentences: Some of their most significant evidence was initially found in Texas, but they might have been present worldwide. Another key region for gigantopterid fossils is in China, and the consolidation of all major continents into Pangea would have allowed for easy global dispersal.