The third dimension: How fire-related research can advance ecology and evolutionary biology

Most of the Earth’s vegetated surface is fireprone but the relevance of fire in understanding how nature works is not always recognized. We aim to show that, by adding the fire dimension to observations on biological phenomena, interpretations can be im-proved; how fire-related research can be used to answer ‘fundamental’ questions in ecology; and how theories/models developed for fireprone ecosystems can be applied to advancing disturbance ecology, biogeography and evolutionary biology more generally. We compiled lists from the world-wide web of the most highly cited papers in fire ecology, and examined papers that had been approached from multiple viewpoints, including fire. We show that great advances over the last 20 years have been made in our understanding of the pivotal role of fire as a driver of many ecological processes and a powerful selective agent/evolutionary trigger among biota. We document 21 sets of observations originally interpreted in the context of the two traditional dimensions, prevailing environment and biotic interactions, but can also be shown to have a strong, if not dominant, historical link to fire. We note that fire-related research is able to address 55 of the 100 questions considered ‘fundamental’ in ecology and that many have already received some attention in fireprone ecosystems. We show how theories/ models that had their origins in fireprone systems can be applied to other disturbance-prone systems and thus have wide application in ecology and evolutionary biology. Fire and other disturbances should be included as variables in research about possible critical environmental and biotic constraints controlling ecosystem function in general. Adding this third dimension to research endeavours greatly enriches our understanding of how nature works at the global scale in an era where ecosystems are changing rapidly and novel species-environmental interactions are emerging.