The postnatal growth of the skull in the house mouse Mus musculus Linné, 1758, and in 2 different large subspecies of the field mouse Microtus arvalis Pallas, 1779. I. Introduction, materials and methods]

In order to describe postnatal skull growth in Mus musculus, Microtus arvalis arvalis and M. a. asturianus, a total of 408 animals were raised and measured. The growth rate of single bones was followed by means of a maximum-likelihood estimator for the parameters A, B and C of the growth function Y(t) = A-B exp(-Ct). Supplementary techniques used to estimate the morphological divergence of the different taxa included methods of allometry research and multivariate statistical methods such as discriminate analysis and MANOVA. Drawings of selected stages of skull-bone ossification are provided to assist researchers in determining the age of undated specimens.