Here’s a time-lapse video from a project I did using Dermestes lardarius to clean a rat’s skull. The project was aimed at showing different imaging techniques i’d learnt during the third year of my Zoology BSc but I used it as an excuse to access the university’s colony of dermestid beetles. To prepare the rat’s head I removed the skin and the brain. 

Larder or Bacon Beetle

Dermestes lardarius

It’s good being a nerd. It took me about 15 minutes to collect, asphyxiate, and identify these two beetles and about 1 minute to figure out that they are a pest that likes proteinus foodstuffs.

External image

I found these two fuckers in my produce bowl on top of the microwave. All I had in there was an avocado, garlic, and ginger root, and none of these were infested, so I think their food source must be something in the pantry above. Most likely my room mate’s part of the pantry above…


The latest episode of Shelf Life, our original web series, is all about the different ways scientists preserve one of the Museum’s rarest and most iconic specimens: the coelacanth. 

But preserving collections for posterity is the name of the game across all departments. One of the more traditional means of preparing skeletons for collections? Getting flesh-eating beetles to do the hard work. Dermestid beetles “will gladly tackle fish, amphibians, reptiles, birds, and mammals with little to no preference,” says Robert Pascocello, senior scientific assistant and keeper of the Museum’s in-house Dermestid colony.

The colony is made up of Dermestes maculatus, or hide beetles, a common species found on every continent except Antarctica. Specimens usually have large organs removed before being placed in the colony, and they are generally air-dried as well to prevent putrefaction as the beetles go about their business. A small bird prepared in this way will be skeletonized by the colony in between one and three days.

Dermestids aren’t picky eaters, and hides, skins, and fabric are all potential meals for loose beetles—or worse, lay eggs that hatch into hungry, hungry larvae. To prevent escapes, the Museum’s colony is kept in a small room with a single door. Temperatures are kept cool to keep the Dermestids grounded, as hide beetles don’t fly in temperatures below 75 degrees Fahrenheit. The tops of the beetle containers are coated with petroleum jelly to deter escapees, and a strip of glue at the door catches any beetles trying to make a break for the exit.

Learn about other methods of specimen preparation on the Museum blog