LampreysFresh WaterLakesPetromyzonGreat Lakes RegionHagfishesFishesSuperior ColliculiPhysiology, ComparativeVena Cava, SuperiorPhylogenySwimmingEutrophicationSpinal CordMesenteric Artery, SuperiorVertebratesReticular FormationCichlidsWater MicrobiologyZooplanktonLocomotionPhytoplanktonGeologic SedimentsPyrrolidonecarboxylic AcidBiological EvolutionChordata, NonvertebrateSuperior Vena Cava SyndromeMolecular Sequence DataEcosystem