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We present a synthetic, structural, theoretical, and spectroscopic study of a family of heterometallic ring dimers which have the formula [{Cr(7)NiF(3)(Etglu)(O(2)CtBu)(15)}(2)(NLN)], in which Etglu is the pentadeprotonated form of the sugar N-ethyl-D-glucamine, and NLN is an aromatic bridging diimine ligand. By varying NLN we are able to adjust the strength of the interaction between rings with the aim of understanding how to tune our system to achieve weak magnetic communication between the spins, a prerequisite for quantum entanglement. Micro-SQUID and EPR data reveal that the magnetic coupling between rings is partly related to the through-bond distance between the spin centers, but also depends on spin-polarization mechanisms and torsion angles between aromatic rings. Density functional theory (DFT) calculations allow us to make predictions of how such chemically variable parameters could be used to tune very precisely the interaction in such systems. For possible applications in quantum information processing and molecular spintronics, such precise control is essential.

Laboratory measurements indicate that observed differences in the rate of water‐loss from inactive Helix aspersa, Otala lactea and Sphincterochila boissieri are due to morphological adaptations such as a thicker shell, reduced aperture and thicker epiphragm. These modifications enable terrestrial snails to inhabit dryer environments by increasing the length of time the snail can remain inactive.

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Studies of terrestrial isopods (Crustacea, Isopoda, Oniscidea) have revealed a capacity for active water vapor absorption (WVA) in the taxonomic sections Crinocheta and Diplocheta but not in Synocheta. Uptake thresholds in Crinocheta are modest by comparison with other vapor absorbers, but standardized uptake fluxes are among the highest recorded and are probably an adaptive requirement to counter the high transpiratory losses. Comparative data for uptake fluxes, thresholds, and transpiratory losses allows the compilation of water budgets in hypothetical temperature and humidity regimes. Given a 12-h light-dark cycle, with saturated ambient activities for diurnal WVA, all species could recover water losses incurred during nocturnal foraging in an ambient water activity of 0.75, and xeric species could forage in activities below 0.30. Xeric trends based on these models agree closely with predictions from ecotypic surveys. In the littoral Ligia oceanica (Diplocheta) haemolymph hyperosmosis and periodic submergence provide additional means of water balance regulation. It is proposed that WVA in Ligia provides an essentially solute-free water source to counteract salt-loading in the splash-zone. The absence of WVA in synochetes, together with their cryptozoic habits, reflects an alternative terrestrial strategy to those of other oniscideans.