As I entered the Environmental Science Center of the Yale Peabody Museum, I couldn’t help but notice the tidiness. The ESC is a beautiful building with clean lines. There is barely any dust or grime — except, I found, in a special basement room. There, a tank of beetles devours the flesh of animal carcasses, preparing the bones for their spotless museum tenure.

So far, beetles have cleaned the carcasses of over 24,000 birds, reptiles, amphibians, and mammals for the permanent collection. However, when specimens (gathered from road-kill, zoos, and research sites) first arrive on campus, they are mere carrion — a mass of fur or feathers, bone, muscle, skin. To be suitably prepared for the archives, these dead animals must undergo a rigorous cleaning process, the final step of which takes place in that basement room: the dermestarium.

Recently, I met with Gregory Watkins-Colwell, the Peabody Museum Assistant, to discuss the preparation process of collected animals and, in particular, the work of the dermestids — the beetles kept as lab assistants.

The process begins when a carcass, usually frozen, arrives at the museum. It is identified, measured, and catalogued. Then the animal is skinned. “It’s like taking a sock off,” said Watkins-Colwell. A skin and tissue sample is then placed in the museum’s databank.

After the skin is off, the lab scientists remove as much muscle tissue and viscera as they can, and then leave the skeletons and remaining flesh to jerky. Only then is the dried specimen ready to meet the beetles.

At this point in the conversation, Kristof Zyskowski, the Collections Manager of Vertebrate Zoology at the Peabody, joined our discussion. He brought me to the ESC’s storage facility — a sterile, chilled area complete with metal cabinets filled with products of evolution. The specimens there are mainly birds — passenger pigeons, ostriches, hummingbirds, and kiwis — and reptiles, but in West Campus facility, Zyskowski points out, there is a narwhale, an recently-extinct zebra known as a “quagga,” a giraffe, a walrus, and a set of champion dogs.

Here are the end results of the collecting process: slightly yellowed bones — all neatly labeled — and various skins. But this is not where the bugs are. They, I discovered, were as far away from the collections as possible.

“We’re working with the beetle everyone else wants to keep out,” Watkins-Colwell explained. So to reach the bugs, Zyskowski led me out of the collections room, through a labyrinth of halls, doors, and stairways. Behind the last door was the prep room.

Immediately, the difference between this working basement and the sterile lab was apparent: it smelled. Humid, thick air greeted my lungs. On the floor, the carcass of a cape buffalo was half-hidden beneath black trash bags. Metal boxes housed preserved fish. In see-through boxes along shelves running the length of the room were small vertebrate skeletons ready for final labeling. Buckets full of bones in various stages of decay were stashed in the sinks.

Still, however, no bugs.

Turning right in the prep room, we came to a second series of doors that led to the beetles.

Housed in glass cages with double-thick wire roofing, thousands of beetles swarmed over the carrion. During my visit, there were several small rodents from an expedition in the 1980’s, a few small lizards, and small birds in the cages. Each half-cleaned specimen, carefully placed in a labeled, clear-plastic tray had its own army of cleaners attacking whatever dried flesh they could find.

Within a few short days or hours — depending on the size of the specimen — those rodents, lizards, and birds will be ready to be placed in storage. After the specimens are removed from the bug tanks, they are shaken to remove most of the bugs and frozen to kill any hidden larvae.

The bugs — more commonly called leather beetles — have a strong affinity for jerked flesh and leathers. So much so, that back before effective pesticides were applied, they were a major fear for the leather industry.

Seeing them with such healthy appetites, I asked Zyskowski what kept them from reaching the even larger feast in the permanent collections upstairs. The most basic deterrent, he said, was the screens on top of the cages.

Even if they make it out of the cage, there is still little chance for escape. The air from the bug room ventilates straight outside the building and not into another room, a feature that also directs the room’s scent away from human offices. Additionally, the bug room is negatively pressured. This means that there is a bug-scale wind tunnel at the base of the doorframe that would stop any adventurous bugs. For good measure, there are also sticky traps in the corner.

After checking to be sure no crafty beetle had hitched a ride on our shoes, Zyskowski and I headed back to the sterile offices above. The beetles, content in their cages, kept right on eating — unknowingly doing the dirty work to create the beauty of the specimens upstairs.