Description: Data derived from a study aimed to detect differences in thermal tolerance by investigating the underlying metabolic responses in the green abalone (Haliotis fulgens) under conditions of hypoxia and hypercapnia. Juvenile abalones were exposed to a temperature ramp (+3 °C day−1) under hypoxia (50% air saturation) and hypercapnia (~1000 μatm pCO2), both individually and in combination. Impacts on energy metabolism were assessed by analyzing whole animal respiration rates and metabolic profiles of gills and hepatopancreas via 1H NMR spectroscopy. The experiments are depicted as warming (warming ramp under normoxic normocapnia), hypoxia (warming ramp under hypoxic normocapnia), hypercapnia (warming ramp under normoxic hypercapnia), and combined (warming ramp under hypoxic hypercapnia). Each experiment was accompanied by a Control group, which was exposed to the same water PO2 and PCO2 but at a stable temperature (18 °C).

Description: MRI of living edible crabs Cancer pagurus submerged in seawater were recorded at 9.4 T. The dataset contains the DICOM files for the respective figures. Anatomical images of the heart were recorded using gradient-echo sequences (FLASH). The structure of the cardiovascular system in vivo was investigated using time-of-flight angiography scans. Haemlymph flow in various vessels was quantified over time with phase-contrast angiography. Self-gated IntraGate CINE MRI could reveal the extent of the heart contraction. FLOWMAP measurements of haemolymph velocity in left and right gills are given, averaging three flow velocities for either side at a specific point in time. Signal and noise values were recorded from anatomical MRI. These values were used to calculate the signal-to-noise ratio for different radiofrequency hardware setups: Images were recorded with either the volume resonator in transmit-receive mode or using the volume resonator for signal excitation and a receive-only surface coil (SUC) for signal reception.

Description: Dynamic in vivo 31P-NMR spectroscopy in combination with Magnetic Resonance Imaging (MRI) was used to study muscle bioenergetics of boreal and Arctic scallops (Pecten maximus and Chlamys islandica) to test the hypothesis that future Ocean Warming and Acidification (OWA) will impair the performance of marine invertebrates.

Description: Lake Baikal is inhabited by more than 300 endemic amphipod species, which are narrowly adapted to certain thermal niches due to the high interspecific competition. In contrast, the surrounding freshwater fauna is commonly represented by species with large-scale distribution and high phenotypic thermal plasticity. Here, we investigated the thermal plasticity of the energy metabolism in two closely-related endemic amphipod species from Lake Baikal (Eulimnogammarus verrucosus; stenothermal and Eulimnogammarus cyaneus; eurythermal) and the ubiquitous Holarctic amphipod Gammarus lacustris (eurythermal) by exposure to a summer warming scenario (6-23.6 °C; 0.8 °C d-1). In concert with routine metabolic rates, activities of key metabolic enzymes increased strongly with temperature up to 15 °C in E. verrucosus, whereupon they leveled off (except for lactate dehydrogenase). In contrast, exponential increases were seen in E. cyaneus and G. lacustris throughout the thermal trial (Q10-values: 1.6-3.7). Cytochrome-c-oxidase, lactate dehydrogenase, and 3-hydroxyacyl-CoA dehydrogenase activities were found to be higher in G. lacustris than in E. cyaneus, especially at the highest experimental temperature (23.6 °C). Decreasing gene expression levels revealed some thermal compensation in E. cyaneus but not in G. lacustris. In all species, shifts in enzyme activities favored glycolytic energy generation in the warmth. The congruent temperature-dependencies of enzyme activities and routine metabolism in E. verrucosus indicate a strong feedback-regulation of enzymatic activities by whole organism responses. The species-specific thermal reaction norms reflect the different ecological niches, including the spatial distribution, distinct thermal behavior such as temperature-dependent migration, movement activity, and mating season.