Lynne U. Sneddon, Javier Lopez-Luna, David C.C. Wolfenden, Matthew C. Leach, Ana M. Valentim, Peter J. Steenbergen, Nabila Bardine, Amanda D. Currie, Donald M. Broom, and Culum Brown, Fish sentience denial: Muddying the waters


Understanding the evolution of nervous and sensory systems in animals is key to understanding the distribution of animal sentience. However, the use of model organisms – mostly vertebrates, and especially mammals – often biases comparative analyses. Sneddon et al. (2018a,b) point out that using nonhuman animals as models helps us better understand the multifaceted aspects of animal pain and sentience. Several concerns need to be considered in dealing with model organisms. Here we discuss how models that are unrepresentative phylogenetically influence hypotheses about the evolution of the myelination in animals. Greater effort is needed to escape “vertebrate-centrism” in evolutionary research.

Author Biography

Michaella P. Andrade is a Master's student in the Graduate Program in Evolution and Diversity, Federal University of ABC (UFABC), studying the evolution and phylogenetic distribution of animal sentience in Eumetazoa via evolutionary and comparative biology. Website

Charles Morphy D. Santos is Associate Professor of Comparative and Evolutionary Biology, Federal University of ABC (UFABC), Brazil, with main research interests in animal evolution, especially systematic, insect, and related group biogeography; epistemology; philosophy of science; and science teaching. Website