Niche partitioning as a mechanism for locally high species diversity within a geographically limited genus of blastoid

Deltoblastus batheri and Deltoblastus delta occur concurrently in many Permian deposits from Timor. Closely related sister species living in direct proximity without alteration in feeding habit would be in direct violation of Lotka-Volterra dynamics. These two species were measured and compared to see if any evidence of differentiation along feeding lines has occurred in order to reduce direct competition. P-values obtained via Student’s t test display significant differentiation across all measured parameters. Thin-plate splines were used to visualize these differences, and clearly show the differences which are focused on the ambulacral region of the blastoids, which are the primary food gathering point for these species.