8 QUATERNARY AUSTRALASIA 23 (1) In 1983 the distinguished ecologist Michael Soulé concluded that “Except for island cases, we know very little about the process of natural extinction”. Despite some headway since, Soulé’s conclusion may still largely hold true. No one doubts that humans are driving the current extinction crisis, but rarely is agreement achieved over precisely which human- mediated influences are responsible or how they interact. However, there is growing consensus in one area: recent extinctions can almost never be attributed to a single cause (Didham et al., 2005). With so many unknowns surrounding extinction in the present, what hope then of truly understanding extinctions in the deep past? Yet, despite the challenges, many continue to focus effort on the disappearance of prehistoric species, and in no area more so than the extinction of Late Quaternary megafauna. Perhaps this should not be surprising. Megafaunal extinction is characterised by charismatic, awe-inspiring creatures and offers other key ingredients: a tantalising potential role for our own species and insight into the current crisis. However, possible human involvement in this prehistoric drama also challenges our objectivity and undeniably inflames passions among scientists and laypersons alike. Historically, megafaunal extinction has been polarised into factions supporting either human or climate mediated causation. Those expressing doubt with respect to competing hypotheses within either category are likely to be labeled as supporters of the opposing camp - you’re with us or against us. Those treating both factors as important contributors have often been marginalised as fence-sitters lacking the courage of their convictions. I consider myself one of these, but think that we fence-sitters represent a growing minority. Increasingly, the question is not whether humans or climate caused Late Quaternary extinctions of megafauna, but how these factors variably combined at different places and times. Indeed, if the invasive species under consideration was not Homo sapiens, either/or arguments might never have prevailed. To illustrate this argument I refer to a study of localised extinction among Caribbean island lizard populations. In 2001, Schoener et al. found that a naturally invading predatory lizard (Leiocephalus carinatus) increased the risk of extinction for a smaller species (Anolis sagrei) in the wake of a major hurricane. Despite serious population crashes, A. sagrei invariably survived where the invasive predator was absent, but went locally extinct on most islands occupied by the new predator. The authors reported this as a rare empirical demonstration of interplay between climatic disturbance and predation, and left it at that. But was it the invading lizard or the hurricane that drove these local extinctions? A case could be made for either, but what would such a blame game achieve? Doubtless victory on the day would go to the most able sophist, but surely, if we truly want to understand what happened to little A. sagrei, we need to first accept that both played a role. The blame game has long been a hallmark of the megafaunal extinction debate, with findings typically presented as strong support for human or climatic causation, a tendency aggravated by media that thrive on simplicity and conflict. Often the stated objective of research into megafaunal extinction is to gain insight into current human impacts. In reality there is more to it than this. Egos, funding and political agendas are at stake. Many archaeologists are sensitive to the fact that placing blame for prehistoric extinctions entirely on the ancestors of surviving indigenous people can fuel vilification. For others, accepting that Homo sapiens, including ‘pristine’ hunter-gatherer societies, were solely responsible for all Late Quaternary extinctions is a catharsis that must be faced if we’re to move current conservation efforts forward (Grayson and Meltzer, 2003; Wroe et al., 2004a). However, if we are going to make this issue relevant we need to pull away from polarised positions and unicausal explanations. At present no single mechanism adequately explains the disappearance of megafauna in the Late Quaternary. GUEST EDITORIAL On little lizards and the big extinction blame game Stephen Wroe School of Biological Sciences University of Sydney (swroe@bio.usyd.edu.au)