"crowded congregations could be unpleasant to unbearably irritating"

February 16, 2019 4:33 PM

There are moths that drink tears from sleeping birds' eyes. There are butterflies that feed on turtle tears. And then there are the wild bees that drink from human eyes. [CW: literally closeup photos of bees drinking from a person's eyes.]

Along with a newly discovered moth [PDF], several species of butterflies and bees practice tear-feeding, or lachryphagy, on mammals, turtles and crocodilia (sometimes at the same time). Back in 2009 researchers chronicled their interactions with tiny native bees in the forests of northern Thailand feeding on their own tears [abstract]. One of the researchers, Hans Banziger, followed up last year with an exhaustive account [PDF] of a four-day encounter with hundreds of the same kind of bees.

Occasionally the landing was so gentle that I did not or just barely noticed it. There are four vantage spots from where she extended her proboscis (well visible in Fig. 5) into the tear trough between eyelid and eyeball: the inner and outer eye corner, the lower and upper eyelid (with front legs resting on the conjunctiva, the other legs on the ciliae). Sucking from the outer eye corner and upper eyelid were much less frequent. In order not to topple from the upper eye lid, the forager had to firmly claw the lid, causing appreciable discomfort. I could refrain from repeatedly blinking the lid and in most cases I eventually had to dislodge the tormentor from this position. Once the bee stopped crawling and started sucking, generally I felt rather little or no discomfort; on occasions I had to check by mirror whether she was still there or not. While sucking, the antennae might repeatedly touch the substrate and then be groomed. At times a burning sensation was felt. As the sucking progressed, the metasoma was clearly seen distending remarkably in length to 1.9 mm in L. cacciae and 2.3 mm in L. furva when fully engorged (dry telescoped state 0.68–1.03 mm and 0.9–1.4 mm, respectively), as well as in width, exposing the translucent membranes between tergal and sternal plates of each segment (Figs. 10, 11). In many cases a slight tickling was felt at the feeding site after she had left. This tickling became a prurigo after more and more bees had been sucking, so that at times I could not restrain myself from vigorously rubbing my eyelid, after having gently dislodged any persisting guest. [...] The presence of several bees felt tickly, and crowded congregations could be unpleasant to unbearably irritating, in which case I collected the bees for counting and release at the end of the session. I interpret this tickling as mainly mechanically-induced unlike the previous instance which may have been chemically-based. A couple of times pinching of the lid occurred.

According to Banziger, the bees go after the tears instead of sweat since they're 200 times richer in proteins than sweat. He writes that with up to 144 tear collecting trips in a day by a single worker and up to 1.5 hours of daily tear foraging, there is "little doubt that lachrymation is not for individual, but for nest requirements in Lisotrigona," with some workers dedicated to that specific task.

posted by not_the_water (19 comments total)

posted by not_the_water

Eponinteresting.

Distinguishing between such alternative hypotheses will depend on. . .
revealing the composition of the birds’ tears and how this can vary throughout different taxonomical groups.

I love my job. But, sometimes I suspect biologists are having more fun.
posted by eotvos at 4:46 PM on February 16, 2019

also observed is the favored beverage of Facultius Horriblis
posted by lalochezia at 4:46 PM on February 16, 2019

... but how do you know he really needs it?
posted by He Is Only The Imposter at 4:57 PM on February 16, 2019 [1 favorite]

CW: literally closeup photos of bees drinking from a person's eyes

I still somehow thought those pics would be way cuter than they actually are and now I have to go to sleep so good one, me.
posted by billiebee at 5:04 PM on February 16, 2019 [9 favorites]

One of the sad reasons that bee populations are falling must obviously be number of tears being harvested and hoarded by trolls and alt-rightists... reason #437 to hate the bastards.
posted by oneswellfoop at 5:25 PM on February 16, 2019 [1 favorite]

whoa seriously you were not kidding about that content warning. Thank you!

Image description for the curious-but-hesitant: First image shows a close up of somebody's opened-wide, bloodshot eye, with about 14 winged insects lined up on the bottom lid, clustering thickly at the inner corner, and maybe 4 or 5 lined up along the inner upper lid. They don't look like your typical fuzzy friendly stereotypical bee that many of us think of when we think "bee." If they weren't named already, I'd have thought they were some sort of large gnat.

Second image has an even larger cluster of insects at the eye's inner corner, but otherwise no long lineups along the lids. There's a short dense lineup (ie, there's no visible space between the insects) at the outer upper corner of this lid.

Thanks for the post! (in my fascinated but shuddering mammal kinda way)
posted by cybercoitus interruptus at 5:33 PM on February 16, 2019 [4 favorites]

The bees were endured just long enough for this photo.

I should certainly hope so.
posted by mandolin conspiracy at 6:08 PM on February 16, 2019

sometimes I suspect biologists are having more fun.

Having looked at the photos, I can only assume that you and I have extraordinarily different ideas of what things are fun.
posted by solotoro at 6:52 PM on February 16, 2019 [5 favorites]

Since it would be very much in the bees' interests to seed eyes with parasites that caused greater, even more protein rich flows of tears, I think these people are nuts.
posted by jamjam at 7:16 PM on February 16, 2019

"Oh, the pain"

-Dr. Smith, crocodile tear extraodinaire.
posted by clavdivs at 7:17 PM on February 16, 2019 [1 favorite]

literally closeup photos of bees drinking from a person's eyes

Just want to emphasize this for anyone who is on the fence

think the ludovico technique, but with bees
posted by schadenfrau at 7:21 PM on February 16, 2019 [5 favorites]

What's the difference between an apiary and a wicker man?

Nothing.

posted by I paid money to offer this... insight? at 7:40 PM on February 16, 2019

Why do I feel like such creatures are part of a Jimi Hendrix song?
posted by symbioid at 8:39 PM on February 16, 2019

I still somehow thought those pics would be way cuter

One bee = cute. 20 bees = alarming (though I still love bees).
posted by amtho at 11:07 PM on February 16, 2019

Some scientists do such bananas things to themselves in the name of science. And that’s admirable, but on the other hand, if I were married to them or something I’d bite my nails into oblivion from worry and also forbid them from doing the thing.
posted by sacchan at 4:35 AM on February 17, 2019 [1 favorite]

They've been reading too much Garcia Marquez. Or somebody.
posted by BWA at 12:11 PM on February 17, 2019

symbioid: Why do I feel like such creatures are part of a Jimi Hendrix song?

Excuse bees
while they kiss my eye
posted by syzygy at 1:37 PM on February 17, 2019 [6 favorites]

So tell me
Have you ever bee ex-tear-ienced?
posted by chappell, ambrose at 2:10 PM on February 17, 2019 [1 favorite]

Wow those bees huh?
posted by Young Kullervo at 2:59 PM on February 17, 2019