Article from PLoS (open access, by definition) explaining that there is a trade-off between performance and energetic costs in electrical signals recorded from single photoreceptors in different fly species. Big blowflies can transmit more information than tiny Drosophila, but their photoreceptors use 10 times more energy to encode the same amount of informaiton. They conclude: “neuronal energy consumption increases much more steeply than performance, and this intensifies the evolutionary pressure to reduce performance to the minimum required for adequate function. Thus the biophysical properties of sensory neurons help to explain why the sense organs and brains of different species vary in size and performance.”
You can read my J Exp Biol attempt to summarise this article, here.