Complex sentence: Richard Leakey's work there in 1967 found some of the oldest remains of primitive homo sapiens, earlier thought to be around 125,000 years old, they may in fact date to c.195,000 years ago.
Split into simpler sentences: Richard Leakey's work there in 1967 found some of the oldest remains of primitive "Homo sapiens". Earlier believed to be around 125,000 years old, more recent research indicates they may in fact date to c.195,000 years ago.