Large carnivore science: non-experimental studies are useful, but experiments are better

1. Response to Bruskotter and colleagues We recently described the following six interrelated issues that justify questioning some of the discourse about the reliability of the literature on the ecological roles of large carnivores (Allen et al., in press): 1. The overall paucity of available data, 2. The reliability of carnivore population sampling techniques, 3. The general disregard for alternative hypotheses to top-down forcing, 4. The lack of applied science studies, 5. The frequent use of logical fallacies, 6. The generalisation of results from relatively pristine systems to those substantially altered by humans. We thank Bruskotter et al. (2017) for responding to our concerns and engaging with this important issue. We agree completely that nonexperimental studies can and do often have great value, and we recognize that in many (most) cases these types of studies may provide the only data that are available. We acknowledge the many challenges of working on large, cryptic, dangerous, and highly-mobile animals in the wild. However, the absence of more robust data and the reality of these challenges do not excuse weak inference or overstating conclusions – a practice apparent in many studies (and communication of those studies) adopting only observational or correlative methods to infer the roles of large carnivores (reviewed in Allen et al., in press)

A global benchmark study using affinity-based biosensors

International audienceTo explore the variability in biosensor studies, 150 participants from 20 countries were given the same protein samples and asked to determine kinetic rate constants for the interaction. We chose a protein system that was amenable to analysis using different biosensor platforms as well as by users of different expertise levels. The two proteins (a 50-kDa Fab and a 60-kDa glutathione S-transferase [GST] antigen) form a relatively high-affinity complex, so participants needed to optimize several experimental parameters, including ligand immobilization and regeneration conditions as well as analyte concentrations and injection/dissociation times. Although most participants collected binding responses that could be fit to yield kinetic parameters, the quality of a few data sets could have been improved by optimizing the assay design. Once these outliers were removed, the average reported affinity across the remaining panel of participants was 620 pM with a standard deviation of 980 pM. These results demonstrate that when this biosensor assay was designed and executed appropriately, the reported rate constants were consistent, and independent of which protein was immobilized and which biosensor was used. (C) 2008 Elsevier Inc. All rights reserved