Morphological evolution Aβ(16–22) peptide assemblies from 1 h to 9 days. Ribbon intermediates are initially observed, but are later replaced by fibers.69 Reprinted with permission from Hsieh, M. C.; Liang, C.; Mehta, A. K.; Lynn, D. G.; Grover, M. A. Multistep Conformation Selection in Amyloid Assembly. J. Am. Chem. Soc. 2017, 139, 17007–17010. Copyright 2017 American Chemical Society.