I once had to make a frog skeleton specimen for a science class assignment. Boiling it to strip off the flesh was fine, but it was easy to end up dissolving the bones as well. Now, with only superworms, the feed for pet lizards, that problem no longer exists. Larvae that decompose animal carcasses have emerged as an eco-friendly technique for making skeleton specimens without toxic chemicals.
A research team led by Professor Mansour Aliabadian of the biology department at Ferdowsi University of Mashhad in Iran said in PLOS One on the 1st (local time) that experiments showed that superworms, the larvae of the American darkling beetle (scientific name Zophobas atratus), are an efficient means of leaving only the skeleton from animal carcasses.
◇Hundreds of larvae decompose carcasses
Skeleton specimens are essential for scientific research and education. By comparing skeletons, researchers can uncover animals' evolutionary processes and even infer behavior. The problem is that it is not easy to obtain only bones from animal carcasses. Flesh is removed from carcasses with enzymes or chemicals, but the expense is high and the toxicity can harm people.
In recent years, insects that decompose animal carcasses, such as Dermestes larvae, have emerged as an alternative. However, Dermestes often develop into adults mid-process and can easily escape elsewhere. As a result, attempts to make skeleton specimens have often led to damage to other valuable collections.
The team tested whether superworms could be an alternative. Superworms are widely used as feed for reptiles, amphibians, birds, and fish, so they are easy to obtain, and they decompose animal carcasses as well as Dermestes larvae do. In particular, unlike Dermestes larvae, they do not develop into adults when kept in groups. That means there is no need to have sealed facilities to make skeleton specimens.
The team let superworms loose on eight animal carcasses of different species and sizes, from an Egyptian fruit bat weighing only 9 g to a wolf weighing 4.2 kg. They had skinned the carcasses and removed the organs in advance. Hundreds of superworms gathered and devoured the flesh of small animals within hours.
The larvae cleanly stripped flesh without damaging even the delicate skulls of birds. Large animals sometimes took more than a day to leave only the skeleton. In those cases, hungry larvae were replenished every 8 hours. The team concluded that 10–15 g of superworms per 1 g of carcass is the optimal ratio for leaving only the skeleton.
◇Best for small research institutions short on funds
Co-author Niloofar Alaei Kakhki of the State Museum of Natural History Stuttgart in Germany said, "Superworms are much faster than other existing methods, environmentally friendly, and very easy to manage."
Dermestes larvae are different. Patrick Campbel, principal curator at the Natural History Museum in London, told Science that "to make skeleton specimens with Dermestes larvae, we keep them in a dedicated 'lab within a lab' completely separated from other collections."
Kakhki said that unlike Dermestes larvae, superworms pose little risk of reproducing while decomposing carcasses, so even small institutions that lack space or funds to rear larvae can adopt them.
Mike Rutherford, zoology curator at The Hunterian Museum of the University of Glasgow, said, "We are looking for a way to remove flesh from snake carcasses without letting hundreds of small ribs tangle or collapse," and added, "our museum does not have separate facilities to rear Dermestes larvae, so we have high hopes for superworms."
References
PLOS One (2026), DOI: https://doi.org/10.1371/journal.pone.0349669