The Academy of Natural Sciences of Drexel University is the oldest natural science research institution in the Americas. Formerly the Academy of Natural Sciences of Philadelphia, it was founded in 1812, by many of the leading naturalists of the young American republic with an expressed mission of "the encouragement and cultivation of the sciences". Located in Philadelphia, Pennsylvania, United States, it has sponsored expeditions, conducted original environmental and systematics research, and amassed natural history collections containing more than 17 million specimens. As a museum the Academy also organized public exhibits and educational programs for both schools and the general public. On September 1, 2026, Drexel University announced that the museum would close its doors on September 30, with the museum's last day open to the public with regular hours being the 27th. The backlash was instant, causing local and national groups to protest and rally to keep the museum's doors open to the public.
History
During the first decades of the United States, Philadelphia was the cultural capital and one of the country's commercial centers. Two of the city's institutions, the Library Company and the American Philosophical Society, were centers of enlightened thought and scientific inquiry.
The increasing sophistication of the earth and life sciences, combined with a growing awareness of the variety of life and landscape in the American wilderness, led a small group of naturalists to establish the Academy of Natural Sciences in the winter of 1812. The academy was meant to foster a gathering of fellow naturalists and to nurture the growth and credibility of American science. They frequently looked to their European counterparts for inspiration and expertise and longed to be regarded as equals. On 25 April 1817 they were incorporated into the society under the title of the Academy of Natural Sciences of Philadelphia by the legislature of Pennsylvania. By 1 January 1818, eight members were published.
In 2011, the Academy became affiliated with nearby Drexel University and changed its name to the Academy of Natural Sciences of Drexel University. Financial Troubles and Closure Throughout the mid-2020s, the Academy faced increasing financial pressures. In September 2025, they announced that they would reduce museum visiting hours and lay off several people. These reduced weekday operating hours also resulted in the cancellation of their children's science camp program in February 2026. On September 1, 2026, Drexel University announced that the museum would close its doors on September 30, with the museum's last day open to the public with regular hours being the 27. The backlash was instant, causing local and national groups to protest and rally to keep the museum's doors open. The William Penn Foundation expressed interest in funding at least a year to reopen the museum.
Notable members Academy members were frequently enlisted to participate in national surveys of the western territories and other major expeditions. Several of its earliest members, including William Bartram, John Godman, Richard Harlan, Angelo Heilprin, Charles Alexandre Lesueur, William Maclure, Titian Peale, Charles Pickering, Thomas Say, and Alexander Wilson were among the pioneers or recognized authorities in their respective areas of study. Thomas Jefferson of Virginia, John Edwards Holbrook of South Carolina, Thomas Nuttall and Richard Owen of the United Kingdom, Georges Cuvier of France, and Alexander von Humboldt of Prussia were among the corresponding members (members who lived far from Philadelphia) of the Academy's first decades.
Later during the 19th century, other notable naturalists and scientists,Distinctions between who is a naturalist and who is a scientist varies and can be elusive. One can make the distinction that naturalists are amateurs interested in the natural sciences, whereas scientists are professionals. This distinction, however, is confounded by history and circumstance. Most of the participants in American science during the 19th century were not professionals, although some of their contributions are of the highest order. including John James Audubon, Charles S. Boyer, John Cassin, Edward Drinker Cope, Ezra Townsend Cresson, Richard Harlan, Ferdinand V. Hayden, Isaac Lea, William W. Jefferis, John Lawrence LeConte, Joseph Leidy,Joseph Leidy, the man who first studied Hadrosaurus, is considered the "father" of American paleontology and American Parasitology and was a leading teacher and authority on microscopy and comparative anatomy. He is widely regarded to have been the leading expert on the natural sciences during the 19th century. More about Leidy can be found on the Academy's online exhibit on Joseph Leidy Samuel George Morton, George Ord, and James Rehn were members. Corresponding members included Charles Darwin along with his supporters Asa Gray, and Thomas Henry Huxley.
For much of its history, new members had to be nominated by two current members and then elected by the remaining members. These requirements were dropped in 1924. Notable 20th-century scientists include James Böhlke, James Bond, Henry Weed Fowler, Ruth Patrick, Henry Pilsbry, H. Radclyffe Roberts, and Witmer Stone.
Collections and research
The Academy of Natural Sciences held an internationally important natural history collection. here were over 18 million biological specimens, and hundreds of thousands of volumes, journals, illustrations, photographs, and archival items in its library. These collections were obtained through multiple means, including the donation or purchase of existing collections or individual items, the collection activities of Academy-sponsored expeditions, or those of individual scientists, whether or not they work at the Academy. Some collections were originally gathered by other institutions. For example, a number of the natural history collections at the American Philosophical Society were relocated to the Academy by the end of the 19th century.
The Academy preserves many type specimens, the reference material that helped establish a species' identity. They also preserved additional specimens with which scientists investigated the nature of these species, their relationships with other species, their evolutionary history, or their conservation status.
Museum collections and research programs
The Academy's collections included a wide range of specimens across the tree of life. The museum also maintained several historically important collections.
Botany Botany is study of plants, including nonvascular bryophytes (mosses, liverworts, and hornworts) and vascular plants, including ferns, conifers and flowering plants. The field of botany has also traditionally included the study of algae, lichens, and fungi which are now classified in different biological kingdoms. Collections at the Academy, which are housed in the Philadelphia Herbarium (PH), the oldest institutional herbarium in the New World, include some of the oldest and most important botanical collections in the Americas. Notable early collectors include Benjamin Smith Barton, Constatine Rafinesque, Thomas Meehan, Thomas Nuttall, and Fredrick Pursh.
The herbarium contains approximately 1.5 million specimens of vascular plants, fungi, lichens, algae, and fossil plants, 40,000 of which are types. It also contains some special collections, including the plants collected by Johann and Georg Forster during the voyages of Captain James Cook, and by Meriwether Lewis during the Lewis and Clark expedition (Corps of Discovery). The department's current focus is plant biodiversity and evolution focusing on Apocynaceae (milkweed or dogbane family) and Polygalaceae.
Diatoms The Academy's Diatom Herbarium, the largest in the Americas and the second largest in the world, contains approximately 220,000 slides of these microscopic algae. The herbarium contains many specimens contributed by notable collectors, a diversity of fossil diatoms, and diatoms collected as part of numerous freshwater environmental surveys in the United States. The Diatom Herbarium also provides collections and taxonomic services for the Phycology Section of the Patrick Center for Environmental Research. Former curators of note include Charles S. Boyer, Ruth Patrick, and Charles Reimer.
Entomology Entomology has been important to the Academy since its founding. Two of its earliest members include Thomas Say, regarded as the father of American entomology, and Titian Peale, a leading natural history illustrator and the chief naturalist on the United States Exploring Expedition (1834–1842). The entomology collection currently contains more than 3.5 million specimens and includes the Titian Peale Moth and Butterfly Collection, the oldest entomology collection in the United States. Curator Emeritus, Daniel Otte, an expert on Orthoptera (crickets, grasshoppers, and their relatives) is a pioneer of presenting biological data on the internet through the creation of the Orthoptera Species File. Curator and Entomology Department Chair, Jon Gelhaus is a leading expert on crane flies and manages the Mongolian Aquatic Insect Survey. Margaretta Morris, a former pupil of Say who was among the first women elected to the Academy and the AAAS, conducted pioneering research on Hessian flies, periodical cicadas (first reported the 17-year cicada Magicicada cassini), diving beetles (cited in Darwin's On The Origin of Species), and other agricultural pests.
Ichthyology Ichthyology has also been a part of Academy collections and research since its beginnings, but the size of the collection was relatively modest until acquisition of Edward Drinker Cope's personal collections in 1898. A few years later, Henry Weed Fowler began his tenure at the Academy, during which he systematized the collections and described 1,408 species. James E. Böhlke, William Saul, and William Smith-Vaniz are among the scientists who followed Fowler. Curator Emeritus, John Lundberg, an expert in catfishes, pioneered deep channel collecting in large tropical rivers and is the lead author of a seminal scientific paper on the biological and geographic history of the Amazon River Basin. The Ichthyology collection, which currently houses nearly 1.2 million specimens and nearly 3,000 types, is one of the most important such collections in the United States. The department also hosts the All Catfish Species Inventory (a comprehensive online resource on catfish) and Catfish Bones (an online digital atlas of catfish morphology), and is a participant in Neodat II (an online resource of Neotropic ichthyology collections).
Malacology Two of the early members of the Academy, Thomas Say and Isaac Lea, were malacologists (see also conchologists). R. Tucker Abbott, Samuel Stehman Haldeman, Henry A. Pilsbry, and George W. Tryon, Jr. were other noted malacologists who worked at the Academy. The Academy's malacology collection is the oldest such collection in the United States and is the 3rd largest in the world. It currently contains over 10 million specimens, including types erected by more than 400 authors. Curator Gary Rosenberg, an expert on Jamaican land snails, is a leader in digitised museum collections and research data. Research websites include the Malacology Georeferencing Project an online database of Western Atlantic Marine Mollusca (Malacolog) , and the OBIS Indo-Pacific Mollusc database. Research associate and former curator Danielle Graf, an expert on Unionidae (freshwater mussels), maintains the MUSSEL Project web site.
Ornithology