Fig. 4: δ15Nenamel versus N content of modern African mammals (colored symbols) and Tam Hay Marklot fossil mammals (black symbols).

The equation for the regression, R2 value, and p value are indicated in the lower right of the figure. Fossil tooth enamel N content falls within the range of modern mammalian tooth enamel N content. δ15Nenamel and N content are not significantly correlated.