April 03, 2016 at 02:43AM

Tody I Learned: 1) So I knew that ants carry their dead to special graveyard recepticles, but today I learned a bit more about that behavior, called necrophoria. When an ant comes upon a dead nestmate, she will scan it briefly with her antennae (solid rule of thumb when it comes to ants -- the first thing an ants does to *anything* is to scan it with her antennae), pick it up, and carry it directly to a graveyard location, usually quite far from the nest. If you house ants in a container smaller than the ideal graveyard radius (as is common in captivity), then the ant will carry her fallen sister to the edge of the container, then wander around the perimeter for several (many?) minutes before dropping it at random. Furthermore, if a dead body is dropped this way, and another ant comes across it, *she* will then pick up the dead ant again and random-walk it around the perimeter some more. Here's the fun part. It turns out that necrophoria is triggered by one very specific class of molecules, specifically olefins produced by the decaying body. If you clean the corpse of olefins and re-introduce it to the nest, workers will eat it or treat it as any other refuse instead of disposing of it properly. Furthermore, if you paint or spray pretty much any other object with the olefins, you can get workers to treat that object as an ant corpse. You can even paint other nestmates as dead ants. If you do, nestmates will carry the painted sister (without resistance) to the graveyard and set her down. The painted sister will vigorously clean herself and wander right back to the nest, where she will usually be picked up and carried right back. 2) My showerhead has multiple action modes! 3) Watched some showcased ballroom dancing today. I learned a few little things (like what a cha-cha looks like), but the thing that really stood out to me was the rhythm of ballroom waltzes. Fair warning, I'm talking from a sample size of about N=3, so it may be too early to generalize, but it looked to me like ballroom waltzes are quite... loose with their rhythm. About half the time, I saw moderately strong "one-two-three" rhythm. The other half of the time was mixed rhythms that kind of sort of fit into the beat. In particular, one of the waltzes looked like it spent a fair amount of time in a one-two-threepausefour rhythm, where the third beat was split into a triplet with steps on the first and third sub-beat, presumably to make the balance or footwork (foot-fingering? footing? what's the word for this?) work out. Ironically, one of the waltzes with the strongest one-two-three rhythm wasn't actually performed to a waltz -- the piece they danced to was 4/4 or 2/4 rhythm, and they just danced three-against-four. Thanks to Mengsha Gong for suggesting I come out to see some dancing, and for a beautiful performance. Also, Sean Chen was awesome, and it was a pleasure to see him perform. Bonus: Bonus ant fact! Today I learned a bit more about how ant identification works. All ants produce a hydrocarbon mix that's unique to the species (or to a few related species), usually with some sub-blend that's unique to the colony and further specifying blends that sometimes identify individuals. The ants produce these hyrdocarbons in specialized internal organs (ants have a LOT of organs for producing chemicals). The hydrocarbons are then distributed internally, and go into cuticle production. Ants also are thought to spit out hydrocarbons and "wash" themselves with them -- in fact, the fastideous self-cleaning demonstrated by ants may be as much to distribute hydrocarbons as it is for hygenic purposes. Also, ants will clean nestmates who have been away from the nest for a long time with extra vigorousness. Second Bonus: Second bonus ant fact! Apparently if an ant finds an offending object in the nest and can't carry it away, it will instead bury it with some dirt. So maybe my pogonomyrmex keep burying their water cap because they find it an offending object?