7 Disgusting Things Butterflies Eat

"Butterflies?” you’re thinking. “But they’re so … fluttery!” And you’re right. They are very fluttery. But their eating habits are revolting.

1. MUD

Let’s start at the beginning. In kindergarten, you were taught that butterflies are nectar feeders, sipping their sugary meals from flowers. This is still mostly true. But nectar is only one food group, and those other nutrients have to come from somewhere.

After a rainstorm, it’s not uncommon in certain areas to see a whole mess of butterflies sitting on the ground, sucking up mud. This practice is known as “mud-puddling” or simply “puddling,” and scientists believe certain butterfly species do it to round out their salt, nitrogen, protein, and amino acid intake.

Naturally, mud is just the beginning.


If you’ve ever visited a butterfly house, you’ve likely seen some delighted small child with a butterfly on her arm. “He likes me!” she says. Delighted Small Child is mistaken. It’s not her friendship he’s after, but her precious, precious sweat. Or maybe he's interested in her tears: In 2014, one butterfly was observed drinking the tears of a sunning spectacled caiman, and photo evidence shows they drink the tears of tortoises, too.

Delighted Small Child might have been wrong about the butterfly liking her, but she probably was not mistaken about the butterfly’s sex, however: Most puddlers are males. Scientists believe that for most butterflies, the sodium goes straight to the sperm, which is then given as a “nuptial gift” to the female, giving the future offspring a better chance of surviving.


Butterflies love urine—“a fact taken advantage of by collectors,” writes the author of the Handbook for Butterfly Watchers. The insects love urine so much that they will even drink their own, which is pretty unique. Aside from a few eccentric humans and astronauts, butterflies are the only animals on Earth that recycle their wee.


Back to the butterfly house. If Delighted Small Child injures herself, her helpful butterfly buddy will be there to help clean up the blood. By drinking it.

From a butterfly’s perspective, larger animals like humans are probably just big restaurants. And what leftovers! Animal poop is full of all kinds of helpful nutrients, which butterflies will feast upon when given the chance.


You know what else is full of nutrients? Dead bodies!

Rotting animal flesh is a huge butterfly favorite [PDF]—so much so that researchers have begun baiting tropical butterfly traps with shrimp heads, chunks of dead snake, and prawn paste. Texture is key; since butterflies have no teeth, the carrion has to be so rotten that it’s actually liquefying. “Traps were baited and checked for cycles of five days, with extra bait added each day to ensure a range of decay,” wrote one scientist in her report [PDF]. Butterfly researchers really don’t get enough credit.

So yes, butterflies are disgusting, but at least they’re opportunists. They’re not out there inserting microscopic catheters or cutting throats with teeny butterfly switchblades. They don’t do the damage. They just enjoy the perks.  

Watch How a Bioluminescence Expert Catches a Giant Squid

Giant squid have been the object of fascination for millennia; they may have even provided the origin for the legendary Nordic sea monsters known as the Kraken. But no one had captured them in their natural environment on video until 2012, when marine biologist and bioluminescence expert Edith Widder snagged the first-ever images off Japan's Ogasawara Islands [PDF]. Widder figured out that previous dives—which tended to bring down a ton of gear and bright lights—were scaring all the creatures away. (Slate compares it to "the equivalent of coming into a darkened theater and shining a spotlight at the audience.")

In this clip from BBC Earth Unplugged, Widder explains how the innovative camera-and-lure combo she devised, known as the Eye-in-the-Sea, finally accomplished the job by using red lights (which most deep-sea creatures can't see) and an electronic jellyfish (called the e-jelly) with a flashy light show just right to lure in predators like Architeuthis dux. "I've tried a bunch of different things over the years to try to be able to talk to the animals," Widder says in the video, "and with the e-jelly, I feel like I'm finally making some progress."

[h/t The Kid Should See This]

Big Questions
Why Are There No Snakes in Ireland?

Legend tells of St. Patrick using the power of his faith to drive all of Ireland’s snakes into the sea. It’s an impressive image, but there’s no way it could have happened.

There never were any snakes in Ireland, partly for the same reason that there are no snakes in Hawaii, Iceland, New Zealand, Greenland, or Antarctica: the Emerald Isle is, well, an island.

Eightofnine via Wikimedia Commons // Public Domain

Once upon a time, Ireland was connected to a larger landmass. But that time was an ice age that kept the land far too chilly for cold-blooded reptiles. As the ice age ended around 10,000 years ago, glaciers melted, pouring even more cold water into the now-impassable expanse between Ireland and its neighbors.

Other animals, like wild boars, lynx, and brown bears, managed to make it across—as did a single reptile: the common lizard. Snakes, however, missed their chance.

The country’s serpent-free reputation has, somewhat perversely, turned snake ownership into a status symbol. There have been numerous reports of large pet snakes escaping or being released. As of yet, no species has managed to take hold in the wild—a small miracle in itself.

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