SlothsPhocoenaAnatomy, ComparativePaleontologyDinosaursFossilsJawPulmonary Stretch ReceptorsBiomechanical PhenomenaSkullFeeding BehaviorPredatory BehaviorModels, AnatomicLocomotionBiological EvolutionMicroscopy, Electron, ScanningSpecies SpecificityPhylogenyMicroscopy, ElectronPhenotypeMicroscopy, Electron, TransmissionCells, CulturedDendritesCell SizeMutationMolecular Sequence DataTime FactorsMorphogenesisCell DifferentiationMicroscopy, ConfocalImmunohistochemistryDendritic SpinesSpermatozoa