Early diversification of ordovician graptolites in Jiangnan Slope, South China.

The article explores the early diversification of graptolites at familial, generic and specific levels through small-scale and high-resolution patterns. A total of ten graptolite zones were examined. It points out a rapid increase in generic and specific diversities in the Tetragraptus approximatus zone. It notes that there are different time intervals in factors causing significant changes in generic and specific diversities in the Jiangnan slope in South China.