Abstract Mossbauer spectra of 57 Fe dissolved in glycerol are compared with spectra of 57 Fe in myoglobin crystals. Above 200 K the strong increase of the 2 >-values obtained from the Lamb-Mossbauer factor is similar for both materials indicating similar dynamics with characteristics times faster 100 ns. Moreover, in this temperature region both spectra are best fitted by a narrow and a broad Lorentzian which indicates the presence of diffusive motions limited in space. “Protein specific motions” become visible in the Mossbauer spectrum above a glass transition. They are characteristics for a hydrogen-bridged network of molecules or molecular segments.