Complex sentence: Goodyear, who began excavating the Topper site in the 1980s, believes that lithic artifacts at that level are, in fact, rudimentary stone tools, although other archaeologists dispute this conclusion, suggesting that the artifacts are natural and not human-made.
Split into simpler sentences: Goodyear, who began excavating the Topper site in the 1980s, believes that lithic artifacts at that level are rudimentary stone tools. Other archaeologists dispute this conclusion, suggesting that the artifacts are natural and not human-made.