I think there are pretty important implications of cell counts. It is probably more apparent if we look at the brain - it has been pretty important to evolutio

I think there are pretty important implications of cell counts. It is probably more apparent if we look at the brain - it has been pretty important to evolutionary biology to study not only the whole number of brain cells but also the proportion that are neurons and the proportions that are other, supporting cells. Similarly, it matters how many cells there are in a particular region of the brain when we ask the question - how did this region evolve to be of this size? If this piques your curiosity I'd recommend Suzana Herculano-Houzel's work - either her popular TED talk ( https://www.ted.com/talks/suzana_herculano_houzel_what_is_so_special_about_the_human_brain https://www.ted.com/talks/suzana_herculano_houzel_what_is_so... ) or this kind of paper if you want to take a deep dive ( http://journal.frontiersin.org/article/10.3389/fnana.2014.00077/abstract http://journal.frontiersin.org/article/10.3389/fnana.2014.00... ) << should be open access. Getting accurate measurements of the numbers of cells gives us a good idea of the number of divisions required to produce them, and could also be used in normalizing cancer risk across organisms. Measurements of types of cells in a tissue give us an idea of the magnitude of the signaling / secretion events from these cells.