ABSTRACT
Arguably the most profound truth about shes (including sharks and rays) is that they grow in length (and weight) throughout their life (Froese, 2006; Hoenig and Gruber, 1990). This is so obvious that we rarely stop to think what this means for the ecology of shes; however, the implications of this truth for understanding how sharks and rays t into communities and ecosystems are often ignored, potentially to the detriment of the eld. The latest trend in ecology is framing biodiversity value in terms of ecological function (Cernansky, 2017). In this approach, species names are substituted with their traits (mined from databases), and the outliers in ecological functional space are identied through multivariate analysis (Violle et al., 2017). Further, we often describe ecosystems as food webs and develop graphs of species (nodes) connected by a web of feeding relationships or
interactions (Paine, 1980). But, does it make sense to assign a single trait value, such as trophic level, to a species such as a tiger shark (Galeocerdo cuvier) that might grow two orders of magnitude in length and three orders of magnitude in weight-from 51 cm total length and about 2 to 3 kg at birth to a maximum length of over 550 cm and a weight of 800 kg?
