Entire museums have been dedicated to showcasing ecological fragility. But in a new exhibition at the National Academy of Sciences, New York-based artist Brandon Ballengée does it with surprising compactness.

Ballengée’s installation, “Collapse”—-a cri de coeur for the impacts of the 2010 Gulf of Mexico oil spill—-consists of a pyramid constructed from glass jars. Though the table can be circumnavigated by foot in just a few seconds, it includes a stunningly broad selection of preserved specimens of aquatic organisms from the Gulf—-26,162, to be precise, representing 370 species.

The jars entomb octopi, rays, crabs, and fish, preserved in fluid that ranges from clear to piss-yellow. The message of the installation is straightforward: We must safeguard susceptible ecologies like that of the Gulf of Mexico.

The pyramidal shape, redolent of disappeared civilizations, is an inspired organizing principle. Yet a lack of clarity about the fate of the species on display muddies the exhibit’s message.

Some jars are left empty, to “represent species in decline or those already lost to extinction,” the exhibit explains. (The jar at the pinnacle, in fact, is empty—-does that represent us?) But if the empty jars represent vulnerable species, then how threatened are the species for which samples are displayed? The seemingly random ordering of species, which are unlabeled, means the answer is not immediately obvious.

An accompanying exhibit called “Ghosts of the Gulf,” consisting of nine color digital scans of aquatic species printed on handmade Japanese paper, raises similar questions. The wall text explains that the printed species “and numerous others may be in decline,” a curiously enigmatic phrasing.

The apparition-like prints, like the rigorously formalistic glass-jar pyramid, succeed visually, but in this exhibit—-hosted by a scientific venue—-Ballengée could have made more effort to shape the raw data he collected into a roadmap for understanding the complicated scientific questions he raises.

Through March 20 at the National Academy of Sciences, 2101 Constitution Ave., N.W., Washington, D.C. Open weekdays 9-5.