The Australian National Wildlife Collection contains specimens of 50,000 birds, 25,000 mammals, 6,000 reptiles, 2,500 amphibians and about 17,000 deep-frozen samples of bird tissue for genetic studies. The specimens are widely regarded as the finest and most useful of all the great Australian wildlife collections. There are two main reasons for this: the geographic spread of the specimens and the quality of the data associated with them.