Echoing a plea from Ron Milo and Robert Last that computational methods [which is sort of ‘math(s)’…] should be used to gain deeper understanding of the fundamental principles that govern regulation of metabolic pathways in plants, here’s advance notice of The Sixth Mathematics in the Plant Sciences Study Group meeting. Taking place from 25–28th March 2013 at the University of Nottingham (UK), this annual workshop ‘gives a handful of plant and crop scientists the opportunity to present a research question to around 40 mathematicians and computer scientists’. At the 4-day number-fest modellers tackle the problems in teams, ‘resulting in a great deal of progress made in a very short time’, which is encouraging. But here’s the real temptation: ‘problems presented at the previous five study groups have led to successful grant proposals, studentships and publications’ (e.g. Scott Grandison). Plus, problems from any area of plant and crop science are welcomed. AND no prior experience of mathematical modelling is required. Can we, er, count you in? And by way of timely proof that numerical approaches can yield botanical insights, we have Pascal-Antoine Christin et al. investigating ‘anatomical enablers and the evolution of C4 photosynthesis in grasses’. The team examined leaf anatomical characters of the co-called PACMAD clade (which contains members using both C4 and C3 photosynthetic carbon-fixation pathways) and the BEP clade (which contains only C3 members), particularly factors as basic as the size of the bundle sheath (BS) cells and the closeness of BSs. Their modelling indicated that evolution of C4 photosynthesis is favoured when the proportion of BS tissue is higher than 15 % (which results from a combination of short distances between BSs and large BS cells). This particular combination of anatomy is found in the PACMAD clade, which is inferred to explain the clustering of C4 origins in this lineage. And, putting that study into a bigger evo-ecophysiological landscape, we have Howard Griffiths et al.’s review that explores the ‘original function of the BS in C3 lineages, providing an insight for selection pressures leading to the derived C4 pathway’. And if you’ve now got a taste for numbers and various C-fixation pathways, Arren Bar-Even et al. ‘survey carbon fixation pathways through a quantitative lens’.