Multivariate zeolitic imidazolate frameworks with an inverting trend in flexibility.

Through systematic linker substitution in a flexible zeolitic imidazolate framework (ZIF) with step-shaped adsorption-desorption, structural intermediates between the known open and closed phases were isolated. Reflecting this, modulative sorption behaviour with an inverting adsorption pressure trend-in which the step pressure decreases and then increases again with increasing mixed linker concentration-is observed, highlighting how linker substitution modifies the energetic landscape of framework flexibility.

Morphological volatility precedes ecological innovation in early echinoderms.

Origins of higher taxonomic groups entail dramatic and nearly simultaneous changes in morphology and ecological function, limiting our ability to disentangle the drivers of evolutionary diversification. Here we phylogenetically compare the anatomy and life habits of Cambrian-Ordovician echinoderms to test which facet better facilitates future success. Rates of morphological evolution are faster and involve more volatile trait changes, allowing morphological disparity to accrue faster and earlier in the Cambrian.