The MVZ houses over 640,000 specimens of amphibians, reptiles, birds, bird eggs or nests, and mammals, as well as over 50,000 tissue samples from these vertebrate groups. These research collections are ranked as one of the largest in the United States, and the largest of any university museum. In addition, the Museum has numerous special collections that include archived field notes and photographs, historical annotated maps and correspondence, avian sound recordings, chromosome and histology preparations, Milton Hildebrand anatomical and film collections, artwork related to terrestrial vertebrate natural history, and a library of books, reprints, and journals for curation and research activities. Specimen data are accessible online , and the Museum is working to improve data access to the other collections.