The ecosystem approach to computer system development is similar to management of biodiversity. Instead of modeling machines after a successful individual, it models machines after successful teams. It includes measuring the evaluative diversity of human teams (i.e. the disparity in ways members conduct the evaluative aspect of decision-making), adding similarly diverse machines to those teams, and monitoring the impact on evaluative balance. This article reviews new research relevant to this approach, especially the validation of a survey instrument for measuring computational (...) evaluative differences in humans (the GRINSQ). The research confirms the existence of all four known machine types among humans. (shrink)