American flamingo pace is maintained by pacemaker cells found in the sinoatrial node, located on the right atrium. The sinoatrial node uses calcium to cause a depolarizing signal transduction pathway from the atrium through right and left atrioventricular bundle which communicates contraction to the ventricles. The avian heart also consists of muscular arches that are made up of thick bundles of muscular layers. Much like a mammalian heart, the avian heart is composed of endocardial, myocardial and epicardial layers. The atrium walls tend to be thinner than the ventricle walls, due to the intense ventricular contraction used to pump oxygenated blood throughout
Node (Well of Echoes) or node-drainers that drain the node of the field and render anything that draws power from it useless. Mancers who cannot draw from a distat node's field must rely on charged crystals, while clankers, constructs and any other devices of the Art will not work. There are also rare places called anti-nodes, where the Art does not work or is at least greatly reduced. Node (Well of Echoes) Nodes are fictional, naturally occurring phenomena in Ian Irvine’s "The Three Worlds Cycle" of novels. They often occur in places where there is a significant landmark, such as on a hill or