 Sarkar’s (2014: 3) consideration of “units” other than species appears compatible with the general pattern–process framework. However, Sarkar’s proposal differs in integrating other additional calculations into the quantification of biodiversity. For example, Sarkar proposed that biodiversity must include a number of aspects beyond richness. At the species-level, Sarkar (2014: 3) argued that a measure of biodiversity should reflect complementarity, rarity, endemism and also “equitability” (reflecting relative abundances). Another aspect to be included was “disparity” reflecting taxonomic distance between species. Sarkar’s consideration of a taxonomic measure of difference between species as part of “biodiversity” echoes the popular objects and differences strategy.