Fig. 1

Shells of foraminifera species that were investigated in this study. The animals lived for their entire life in their natural marine environment. The structural characteristics of shells are used as reference for those organisms that were transferred into Cd²⁺ or Pb²⁺ contaminated water and secreted their last chambers in Cd²⁺ or Pb²⁺ environments. (A, B): SE micrographs of A. lobifera and A. lessonii shells. The reference shells were sectioned in two directions: cut A is a cross-section, cut B an equatorial section. (C) to (F): BSE images of the surfaces that were investigated with EBSD. In contrast to the first-formed chamber walls, the chamber walls that are formed as last (yellow star in (E), (F)) have thinner walls. The dashed white line and white stars in (F) indicate the position of the as last formed chamber wall; the latter became broken at microtome preparation. Modified after Fig. 1 in Yin et al. (2021)⁶.