MammalsEndangered SpeciesExtinction, BiologicalConservation of Natural ResourcesRodentiaArvicolinaeBiodiversityPopulation DensityShrewsDolphinsPopulation DynamicsEcosystemGeographyClimateSpecies SpecificityBody SizeBiological EvolutionPhylogenyTreesEvolution, MolecularMolecular Sequence DataModels, BiologicalMarsupialiaPinnipediaReptilesCetaceaAmino Acid SequenceInsectivoraBirdsFossilsVertebratesSeals, EarlessCarnivoraBase SequenceArtiodactylaEchidnaMonotremataSequence AlignmentSequence Homology, Amino AcidMacropodidae