Conference: Integrating the History and Philosophy of Biodiversity.

The present global biodiversity crisis is often referred to an ongoing “Sixth Mass Extinction,” an explicit reference to the five major mass extinction events identified by paleontologists in the geological past. There is obvious rhetorical advantage to presenting current events in this way: since the 1980s the public has been well-informed about mass extinctions—particularly the event that ended the dinosaurs’ rule—and the implied message is that we as a species may be inflicting on ourselves what happened to the dinosaurs by chance.

Whether or not current diversity estimates and species extinction rates actually match those of past events—or whether past and present data can even be meaningfully compared—is another matter. Nonetheless, since the beginnings of the organized biodiversity movement in the late 1970s frequent and explicit comparison of past and current extinction rates has been a central feature of the rhetoric. In other words, calling the biodiversity crisis a “Sixth Extinction” is an empirical claim, not just a compelling analogy.

This talk will examine the origins and consequences of that empirical basis as it moved from a rather obscure entomology journal into the mainstream of scientific and eventually public biodiversity conservation discourse. It will highlight the important role that paleontology and paleontologists have played in this process, both as a source of empirical and moral support, and as critical foils for biodiversity advocacy. In particular, the talk will focus on E.O. Wilson as a key conduit between paleontological and biological contexts for diversity analysis, and it will raise questions about whether biodiversity advocates successfully—or honestly—reconciled key differences between data, methods, and scale in past and present crises. And it will conclude by asking whether “biodiversity” is, itself, a coherent or stable concept.

Prof. Sepkoski is the Thomas M. Siebel Chair in History of Science at the University of Illinois.

How is biodiversity changing at the local scale? What are the effects of livestock grazing on biodiversity? How do invasive species affect biodiversity? How does diversified farming affect biodiversity? What is the effect of organic farming on biodiversity? How does functional redundancy affect ecosystem resilience? One thing that these questions have in common is that they have been given different, sometimes even conflicting, answers. But how should we understand these divergent results? One (historically quite popular) interpretation would be that there is something fishy going on in some (or all) of the research, such as flawed experimental design, replication failure, etc. More, recently, however, ecologists and conservation biologists have been using a different toolkit to analyse primary research and are increasingly able to make sense of these divergent results. This toolkit consists of systematic review and meta-analysis (SRMA). This toolkit remains quite controversial, as scientists and philosophers alike have documented numerous shortcomings, such as various types of bias. However, most of these critiques focus on SRMA in the field of medicine. While I agree with these critiques in the context of medicine, I argue that SRMAs in ecology and conservation biology are different in two key ways: (i) there are important differences between medical and biological primary studies (i.e. what SRMAs are based on), and (ii) SRMAs in ecology and conservation biology are used differently than those in the medical sciences. That is, biological SRMAs are aimed at exploring the scope of generalisations, hence they can succeed in explaining why we see such divergence in the results of primary studies. In light of these differences, I caution against dismissing or underestimating the value of the SRMA toolkit in the context of ecology and conservation biology.

Prof. Elliott-Graves is Junior-Professor of Philosophy at Bielefeld University.