 This pre-history considered variety at more than the species level. Farnham (2017) provides a useful historical perspective, describing how the standard three levels of variation later recognised by the Convention on Biological Diversity (CBD)—genes, species, and ecosystems—became established early as parts of our broader concern about the loss of living variation. He describes this as a convergence of separate concerns about species loss, loss of genetic variety, and the disappearance of ecosystem types. Other support for this convergence is found in early work referring to the variety of biomes or ecosystems as capturing variety at the species level. For example, Ehrenfeld (1970) referred to the potential but unknown uses of species and suggested conserving the full variety of ecosystems to capture these future options (arguing that every ecosystem is likely to have some useful species). Back in 1972, the botanist, H. H. Iltis, argued that we must “preserve sufficient diversity of species and of ecosystems” because “we will never reach a point where we shall know which organisms are going to be of value to man and which are not” (Iltis 1972: 204). Ehrenfeld referred to the need globally to conserve a representative set of the different ecosystems (see also Roush 1977). Echoing these concerns, Wilson (1984) later lamented the lack of representativeness of the variety of ecosystems in the current protected areas system.