New Publication: Assessing Soft-Tissue Shrinkage Estimates in Museum Specimens Imaged With Diffusible Iodine-based Contrast-Enhanced Computed Tomography

Pallas’s long-tongued bat
Mid-sagittal section of museum specimen of Glossophaga soricina (Pallas’s long-tongued bat) head after three weeks in I2KI stain demonstrating complete penetration after only several weeks in stain. The black space surrounding the brain shows the degree of shrinkage. Anatomical structures are outlined for orientation. Scale bar = 4 mm.

DiceCT allows visualization of organismal soft-tissue cheaply and non-destructively, thus giving comparative biologists a new toolkit for assessing morphological variation. Comparative morphologists primarily use museum collections to visualize features across a wide range of species, but the consequences of preparation and storage are not well understood. We report soft-tissue shrinkage in the brains and eyes of five bat species from museum collections and compare this to shrinkage found in specimens of six freshly-collected species. Although the magnitude of shrinkage in the museum specimens did not increase over four weeks of stain time in iodine, the brains and eyes of museum specimens shrank considerably prior to placement in iodine in comparison with field-collected specimens. While the cause of shrinkage in these specimens remains unknown, we caution against study designs that combine fresh and museum specimens.

Lead author, Brandon Hedrick (@)

Read more about using diceCT with museum specimens at Microscopy & Microanalysis!