Histogram plots are shown for myofibre cross-sectional areas (CSA) from the naso-, oro- and laryngopharyngeal regions of wild-type FVB mice at 2, 12 or 24 months of age. A, myofibre CSA significantly increased from 2 to 12 months of age in the naso- and oropharynx but decreased in the laryngopharynx. n = 752–1943 myofibres, three to four mice per time point. B, myofibre CSA decreased from 12 to 24 months of age in all pharyngeal regions. Data from 12 months of age are shown again for comparison. n = 792–1943 myofibres, four mice per time point. mo, months.