Profound reversible seasonal changes of individual skull size in a mammal

Postnatal size changes in most vertebrates are unidirectional and finite once the individual reaches full size [1West G.B. Brown J.H. Enquist B.J. A general model for ontogenetic growth.Nature. 2001; 413: 628-631Crossref PubMed Scopus (807) Google Scholar]. In rare cases, changes of body length may occur in response to harsh environmental conditions. Such reactionary changes are distinct from seasonal, often anticipatory morphological changes,...