Flesh-Eating Beetles Explained

Flesh-eating beetles, called dermestids, are nature’s forensic scientists.

The word “dermestid” derives from the Greek word meaning “skin,” and the insect is aptly named. These creepy crawlies will eat the flesh off carcasses in a process called skeletonization. (Also see “Flesh-Eating Caterpillars Discovered in Hawaii.”)

Dermestid beetles at work. Photograph courtesy Ken Hansen

Wildlife law enforcement agents use the beetles to expose skeletons when harsh chemicals might damage evidence, such as marks on bones. Museum curators and taxidermists also use the bugs to clean skeletons for research and displays. Hundreds of dermestid beetles are often used to pick a cadaver clean.

It’s a low-tech solution to an ordinarily high-tech problem, said Ken Hansen, a retired federal game warden with the U.S. National Oceanographic and Atmospheric Administration, who has been selling dermestid beetles for six years.

“I can recall one instance where they actually had a skull, and they were trying to clean the skull for a potential murder investigation, and the beetles were used to clean the skull,” he added. “There certainly is a use for these forensically.” (See “Museum Secrets Unmasked by ‘Museomics’ Technologies.”)

Dermestid beetles pick a skull clean. Photograph courtesy Ken Hansen

For those who can stomach the stench, it’s an incredibly engaging process—emphasis on the “gag.” Check out this viral video of parrot versus flesh-eating beetle—we’ll let you guess who wins. 

Beetles Be Eatin’

In the wild, the 12-millimeter-long scavengers decompose animals long since expired. But if you live in North America, they can also lurk in your walls or under floorboards.

Once indoors, the grubbers expand their palates. According to the U.S. Fish and Wildlife Service Forensics Laboratory, dermestids will eat their way through materials like old books, carpets, or woolens.

This appetite for anything organic sometimes makes them a nuisance for museum personnel and taxidermists. Though it’s rare, adult dermestids have been known to fly, and escapees that find their way into exhibits can do considerable damage.

Flesh-eating beetles on the loose sounds like an Alfred Hitchcock movie, but people need to worry more about their linens than their limbs. 

There’s an urban legend about the beetles getting out in large numbers and destroying things, Hansen said, but they don’t eat living flesh.

Or, at least, not that we know.

Get more bug news:

Vomiting Caterpillars Explained

Bugs’ Battle of the Sexes

Dung Beetles’ Favorite Poop Revealed


Mollie Bloudoff-Indelicato is a freelance science journalist who loves em dashes, ’80s music, and water policy. She has a master’s degree from the Columbia University Graduate School of Journalism with concentrations in science journalism, photography, and radio reporting. Contact her at news@mbloudoff.com, and follow her on Twitter at @mbloudoff.

Mollie Bloudoff-Indelicato is a science journalist who loves em dashes, ’80s music and parasites. She has a master’s degree from the Columbia University Graduate School of Journalism with concentrations in science journalism, photography, and radio reporting. Contact her at news@mbloudoff.com, and follow her on Twitter at @mbloudoff.
  • John Smith

    very interesting article, but there is no mention as to how long it takes to strip a carcass down to its bones. For instance, how long would it take the beetles to strip a dead cat or dog completely? And as for the smell, cannot one just let the beetles work in an enclosed space or would they quickly suffocate? And are they faster at their work than say woodlice or ants or maggots? Does anyone have such information please? Thanks. John

  • Geoff

    Just a question.

    Would the beetles eat flesh which had been contaminated through disease?

  • Jarrod Lea

    Great article. I have kept dermestids for years, they do a great job. JoyceFrank……no they don’t. John Smith, depends on the size of the colony. A large colony should strip a cat or dog in under 2 weeks. The colony needs to have adequate airflow or the enclosure can become damp which will affect the health of the beetles. The beetles themselves don’t smell so as long as you keep the enclosure/bedding relatively clean and dry and the colony is an appropriate size for the specimen, smell can be kept to a minimum. Maggots are faster but dermestids will give you a much better specimen with a soak in hydrogen peroxide and rinse in water after cleaning the only things you have to do. Geoff, I have never found a diseased specimen to try but I don’t think they would care. If you are unsure of the age of the carcass or it has been exposed to the elements you should always freeze the specimen before introducing it to the colony to ensure the health of the beetles.

  • Cutie Ann

    I have been dealing with this beetle larvae since March of this year. Without any actual neurological analysis, my doctor diagnosed me with Ekbom’s Delusional Parasitosis. Long story short, one of the Dermestid Beetle Larvae fell out of my nostril on Tuesday, October 11th, 2016.. I took it to an entomologist for proper identification which is how I was able to put a name to this thing. Even though it has been sealed in a Ziploc bag and wrapped in aluminum foil, it is still alive, my body is infested, and no doctor seem to be brave enough to remove these things from my body because of one doctor’s inability to perform the proper testing and provide an accurate diagnosis.

  • Rnaomi

    I’m writing a book and looking for an aggressive, carnivorous species of beetle. Does anyone know if these beetles have aggressive temperaments? Otherwise, they seem to be perfect, if a little tame. I just don’t want to perpetuate any myths if possible.

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