Figure 3: Scanning electron micrographs show ductile deformation of typical multicellular fibres at high RH.
From: Study of the tensile properties of individual multicellular fibres generated by Bacillus subtilis

Viscoelasticity gradually dominates deformation of the fibres at high RH. The fibre elongates significantly both in the bacterial cells and at the positions of septa, and necking failure occurs.