This article reports on the origin, evolution, and diversification of the iron-sulfur (2Fe-2S) binding motif CDGSH.

Article explores the ‘membrane pacemaker’ hypothesis which proposes a biochemical explanation for among-species variation in resting metabolism, based on the positive correlation between membrane docosahexaenoic acid (DHA) and metabolic rate. The authors tested this hypothesis using a novel model, altricial red-winged blackbird nestlings, predicting that the proportion of DHA in muscle and liver membranes should increase with the increasing metabolic rate of the nestling as it develops endothermy. In support of the membrane pacemaker hypothesis, DHA proportions increased in membranes from pectoralis muscle, muscle mitochondria and liver during post-hatch development. By contrast, elevated dietary DHA had no effect on resting metabolic rate, despite causing significant changes to membrane lipid composition.

Article describes a study which examines the conduction system in crocodiles (Alligator mississippiensis), the only ectothermic vertebrates with a full ventricular septum.