‘Ecosystomics’: ecology by sequencer J

relationships between uni- and multicellular organisms en masse. Such methods have the potential to identify every organism within a given sample, exposing the diversity of nature that is both visible and invisible to the human eye. Yet, diversity reveals neither what those species are doing nor how they interact. Metagenomic approaches are ‘ecosystomics ’ with a straight face. More seriously, this erosion of practical barriers to genomic understanding opens numerous doors and requires reassessment of the limits of reductionism in ecology. The looming challenge for ecologists is to establish how far metagenomics can productively be taken. A cell biologist might well argue that there is little to gain from mapping the location of every atom in a cell. Nevertheless, if one dared to take a hectare of rainforest, perform the molecular equivalent of placing it in a blender, and sequenced the resulting nucleic acids, what could be learned? One thing seems certain: the answer would not be ‘nothing at all’