We have recently confirmed previous reports that Heliconius have massively expanded mushroom bodies (see Montgomery et al. 2016 J. Comp. Neurol. 524 (9):1747-1769), providing a novel case study for investigating the causes and consequences of volumetric expansion of 'higher order' brain regions. We are interested in understanding the cellular basis of mushroom body expansion by investigating how the number of neurons and synaptic complexes vary with size, and by testing the hypothesis that mushroom body expansion co-occurs with changes in input to the mushroom bodies from other brain regions.
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