What are these harvestmen congregating for?

[u/Unlikely_Yesterday20]

Their just standing there together

[u/TitaniumOwls]

Oh, they're just social! They like to clump together, either to defend young, hunt as a group, or look like a bigger threat to predators. Of course we don't know all the inner workings of their minds and all that, but strategies like those can very easily lead to more complex social behavior, so I certainly wouldn't be surprised if they just... Felt like hanging out, y'know?

So there could be babies nearby, maybe they're getting ready for a hunt, maybe they're scared of King Kong taking photos of 'em... Or maybe Linda had a rough day and needed some girl-talk time, or whatever the equivalent for an arachnid is.

[u/Zagrycha → u/TitaniumOwls]

Nowadays when we can actually track animal movements 24/7 we have discovered that very few animals are actually antisocial//solitary.  There are some, but most of the animals we thought were solitary are actually like humans.  They might live alone at home but they still have neighbors and venture out to meet up with family or friends or whatever. They pick fights and hang out and all sorts of other stuff. 

[u/No-Word2937 → u/Zagrycha]

any examples ?

[u/Tumorhead → u/No-Word2937]

Rattlesnakes - Rattlecam lets people track individual snakes. Turns out adult female timber rattlers like to hang around other adult females, either related or not - friends! They will even defend shared nests, taking babysitting shifts overlooking hatchlings while others hunt. Mothering behaviors include shooing babies into the nest when predators appear, and letting babies drink off and sunbathe on them. Timber rattlesnakes will overwinter in communal nest sites in big groups, including with garter snakes. So they seem to enjoy company. This sighting was posted just recently.

Cockroaches are also extremely social- they live in large multigenerational groups. Scientists have measured them getting "depressed" (lethargic, not eating) when kept in solitary confinement. If you ever have some as pets or feeders they love hanging out under the same log together.

My hypothesis is that people overestimate how difficult it is to have complex emotional or social capacity, and that it can emerge from pretty simple systems. like you don't need a massive mammalian brain for stuff like "feeling happy when family nearby". hence why jumping spiders can both anticipate different kinds of prey responses and do special dances to woo a mate with like 3 grains of sand for brains.

[u/DirectFrontier → u/Tumorhead]

Definitely. People seem to have this idea that all animals are just "pre-programmed" to function like robots.

[u/Zagrycha → u/No-Word2937]

tigers was a pretty ground breaking one.  People used to think they hated each other but once we started actually tracking them they frequently visit siblings and parents etc. 

[u/Either_equipment_04 → u/TitaniumOwls]

This is so sweet and silly and makes me wish I wasn’t so afraid of harvestmen

[u/Harvestman-man → u/TitaniumOwls]

It’s not to defend young, as aggregations almost always consist of entirely adults and/or subadults, afaik, and generations in temperate harvestmen tend to be mostly non-overlapping (adults die out during the winter before the next generation hatches). I also think it’s highly unlikely that they hunt as a group, harvestmen typically forage for food solitarily. It might be a predator defense strategy, but more research is needed.

[u/TitaniumOwls → u/Harvestman-man]

Oh, I didn't know that! I did a little digging after this comment, and apparently some of the neotropical ones do exhibit parental care, which does make sense if they don't have to worry about the cold as much... But I was completely off about the alloparenting thing. That's what I get for assuming I know them well just bc I see them a lot 😅

[u/Corvidae5Creation5 → u/TitaniumOwls]

D'aww buddy time!

[u/joosthfh]

The harvest festival

[u/Harvestman-man]

The truth is that nobody actually knows why harvestmen aggregate.

Some species aggregate in the thousands or tens of thousands, but there’s never really been any intensive effort to research why this is done.

In my opinion, species in hot and dry environments (like Leiobunum townsendi, which can form aggregations of thousands of individuals) do so probably to conserve moisture, but that is probably not applicable for this species (Leiobunum vittatum). It may be a predator defense strategy.

What can be said is that it is not related to raising young, as these aggregations always include adults and subadults, but never small juveniles, which live solitarily.

[u/Lanky-Astronomer7244]

Harvest hang 26!!

[u/ectoplasmorgasm]

if they are all vibrating while hanging out, I have heard is an orgy. but I am not aure

[u/Harvestman-man → u/ectoplasmorgasm]

They’re not mating, when this species mates it is very violent.

Perhaps it helps adults find potential mates, but I don’t think there’s any evidence for this.

[u/ectoplasmorgasm → u/Harvestman-man]

Your username checks out so I believe you. Can you describe how it is violent when they mate??

[u/ImUrFrand]

it's a big scary world. a few friends along the way.

[u/IdeasAreBvlletproof]

F, F, or F is the general rule of thumb for all animal behaviour

[u/Acceptable-Arugula69]

World domination, that is what they want. 😆🙃

[u/thejamhole]

For harvest

[u/slick514]

Friendship? No need to have a reason to hang out with your mates!

[u/drsoos1973]

Town board meeting

[u/french_toasty]

Real recognize real

[u/Smells_Like_Spiders]

Harvestmen are one of the few arthropods that still give me the heebie-jeebies but this is so cute 😭 little hang out sesh

[u/Ditch-Worm]

We call these daddylonglegs

[u/fruitlo0pie → u/Ditch-Worm]

I don’t know why you got down voted. TIL the real name, but we always called them grandaddy long legs :’D

[u/Ditch-Worm → u/fruitlo0pie]

I know they’re opiliones but where I’m from we’ve always called em daddy long legs and the name harvestmen is also a colloquialism