hugabug 13: Fecal shield

from Hall & Butler 2001 (University of Florida Institute of Food and Agricultural Sciences, Document EENY-232)

Some beetles reuse their poop by wearing it.
Listen to find out how and why.

Right-click or Command+click to download

Music in this show:
1. Rafter, “Feels good”
2. Balkan Beat Box, “Blue eyed black boy”
3. Battles, “Inchworm”
4. Rafter, “Timeless form, formless time”
5. Spanglish Fly, “Let my people bugalú” (Clay Holley and Jeff Dynamite remix)

— — — — —

If poop serves a useful purpose, then you can’t really call it a “waste product”, right? Some beetles reuse their dung by wearing it for protection.

The palmetto tortoise beetle does look sort of like a tortoise, with its domed back and flat belly pressed against a leaf. When it’s young, though, crawling around as a larva, it looks more like a tangle of tiny sticks. Or maybe like a big, heavy, looped string of tiny linked sausages. It seems to wear something like a giant straw hat of feces that hides its entire body.

photo by Dr. Rebecca Forkner

And that’s the whole point! Dangerous enemies can’t get past the wall of poop that the beetle larva built for itself. The tortoise beetle uses its telescoping anus to spool its dried poop in coiled layers over the top of its body. It can point its anus in different directions to build the most effective wall of poop between itself and the dangers of the world.

For other beetles, too, their feces don’t just plop out as wastes. Some beetles create fecal shields, which they hold on their butt and can position in the direction of an attack. Sometimes the poop shield is toxic, because of the chemicals in the beetles’ food plants.

from Vencl et al. 1999 (Journal of Chemical Ecology)

The defense is even more effective when social beetles respond to attackers by forming a tight circle–heads in the center, butts on the outside–holding up all of their fecal shields. Attackers can’t get past the solid blockade of toxic poops.

For these beetles, poop serves them well through most of their lives. Even as eggs, the beetle babies are protected by their mother’s poop. The momma defecates on her eggs; the crusty poop shell resists predators and may camouflage the babies.

from Prathapan & Chaboo 2011 (ZooKeys)

Now, I don’t necessarily think that you should wear a poop hat, nor that it’s good advice to hide behind your excrement or to use it as a weapon. Butt–these beetles teach us the utility of recycling! Recycle as much as you can. It’s not waste when it’s useful.

And hug a bug. You can wash your hands later.