Oh Oh Speaking Of Fruit Fly Behavior, I Hadn't Seen It When I Reblogged This Post Before But Someone

bugs are always cleaning their damn antennas

Invertebrates are definitely capable of learning! A lot of people who don’t know anything about bugs say they’re automata who just do everything by instinct like an if-then computer program, and they absolutely have not looked into it because there’s SO much literature on invertebrate cognition including learning. One of the neatest papers I’ve seen was about Drosophila fruit flies (there’s a ton of fruit fly literature cuz they’re a common lab animal). So when a female fruit fly is exposed to parasitoid wasps, she will start laying fewer eggs. These researchers showed that fruit flies who have been exposed to wasps can communicate the presence of a threat via wing movements to other female fruit flies, and those flies will start laying fewer eggs too even if they haven’t seen the wasps at all, an example of social learning.

But what’s more: they can communicate threats like this not just with flies of their own species, but with flies of closely related species too. If the species are too distant, they stop being able to communicate as successfully HOWEVER these authors showed that if you house a bunch of flies together in mixed-species groups, afterwards their success at communicating goes up! This suggests the existence of a fruit fly “language” which differs between species, but which they’re capable of learning other species’ languages as well! Sources: 1, 2

see also this very scientific diagram from here:

One interesting thing about those studies is that they found that if you raise a fruit fly in isolation from hatching, it won’t be able to communicate as well. This suggests that there’s a critical period of socialization which flies require to learn how to do communicate properly and without it their ability to do so is impaired. (I believe there’s other studies on how other social interactions are affected by social isolation but I haven’t read them; again there’s sooo much fly literature ^^)

Another cool one I’ve seen is on antlion larvae, who hunt by digging pits and then waiting in the middle for ants and other bugs walking by to fall in. It’s generally thought that sedentary animals have fewer cognitive capabilities than mobile ones, due to their less demanding lifestyle, however these studies (which I’ve only skimmed) have been carried out which demonstrate that they are still capable of learning. Specifically, they can be taught to anticipate and identify approaching insects based on vibrations in the sand, and will subsequently adapt their behavior to hunt more efficiently! Even animals with what seems like a simple feeding behavior are still very capable of modifying it, which makes sense evolutionarily; while obviously different animals will require different levels of intelligence, you can imagine in a lot of cases that being able to modify your behavior based on experience is distinctly advantageous. Source 1, 2

Not an arthropod, but another bug that there’s been a lot of research into is Lymnaea pond snails, which are another common model organism for studying neurology and cognition. A ton of work has been done on their capabilities for associative learning, i.e. classical conditioning (“dog learns to salivate at the ring of a bell”) and operant conditioning (“rat learns that pressing a button gives food”). It’s been found that their ability to learn is actually a lot more complicated than just those simple kinds of stimulus ↔ response. They can take stuff they’ve learned in stressful situations (simulated experimentally by exposing them to the smell of crayfish, which eat snails) and generalize it to situations beyond just the original context, which you can imagine must be pretty important for surviving in the wild. Conversely, they can also place memories in context: when taught stuff in the presence of both crayfish smell and carrot smell, subsequently they will recall what they’ve learned in response to the carrot smell alone; in other words, they’re not just learning “carrot + crayfish smell”, but “carrot smell = crayfish smell”, placing their memories in the broader context of their environment (which again, must be helpful for survival). So they can not just learn but pretty flexibly as well! Sources 1, 2, 3

This isn't a bug at all but pretty recently there was a study that found that box jellyfish are capable of associative learning. This one research lab has done a lot of work into vision in the Caribbean box jellyfish (they have eyes btw) on both a behavior and a neurological level and have found a lot of cool things, like that these box jellyfish use their vision to navigate through their habitat of mangrove forests, and that though they don't have a brain as such, they do have a central nervous system in the form of a ring nerve connecting four small clusters of neurons that process and combine input from their eyes. I can't actually read the paper (paywall :P) but last year they did an experiment where they put jellies in a tank with darkened bars on the glass to simulate mangrove roots. Normally the jellies gauge the distance to a root by how dark it appears and then swim around it when they get near; however the bars in the experiment were colored so that they looked like they were farther away than the wall actually was. At first the jellyfish kept bumping into the all, but after several rounds of trial and error they began to avoid them, indicating that they were able to learn from the experience! Jellyfish! Aaaaa nature is so cool. Source 1, 2, 3

I have a question! About bugs and arachnids and all them. Sorry to lump them all into one category, but I'd rather not make the same post multiple times.

My question is: Can they learn "tricks?"

By this I mean are they capable of learning, in general, I suppose. Like mice in a maze, magpies with a rock.

Also, what sorts of things have they learned? How do they learn (like watching others or from experience)?

I ask because it's something that really interests me. I know the ability to learn doesn't add or subtract value from a being, it's a curious thought as I know very, very little about beetles, and spiders, and bees, and so on!

Do they just know how to do things because it's all their kind have done since the beginning of them? Do they have to learn or are capable of it?

scientists: oh hey we found a new species of deep sea feather star, neat :)

the news: TERRIFYING and ALIEN creature with ONE THOUSAND ARMS discovered LURKING in the DEEP ABYSS of the sea

the public: omg im never swimming in the ocean again!!!

the animal:

:)

:D

:3

:V

their hair makes them look so round and fat

During the storm, I've had a wasp sheltering on my window.

It's been two days now, and she's still there, so I gave her some honey

Lookit her! slurping away!

@onenicebugperday

Submitted comment: “I wanted to submit this paper from 2021 which is like. one of the single most aggressive academic papers I have ever seen; for context there are as I understand currently two main strains of thought as to where life first evolved— in submarine alkaline hydrothermal vents, or in above-water volcanic hot springs. The author here I believe is one of the original proponents of the hydrothermal vents hypothesis, defending it against some recent publications from the hot springs camp criticizing it for lacking evidence, and it gets. heated. The whole thing is kinda nuts but this paragraph in particular actually had my jaw actually drop reading it”

Here we counterface all the arguments made in recent papers from the very well-funded and promoted groups militantly opposed to AVT. One of these papers offers the advice “Don’t try to prove an idea is right. Instead, try to falsify it”. Fully cognizant of Popper’s “Reason and Refutation”, this has long been our own mantra, though notably unshared across the community. As an example of good faith, Branscomb and colleagues wrote, “arguably the key virtue of the alkaline hydrothermal vent (AHV) model as a scientific hypothesis regarding the initial steps in the emergence of life is its essentially unique vulnerability to disproof. It places all of its chips on the claim that certain naturally arising, but experimentally reproducible, geochemical circumstances do produce castles of mineral ‘cells’ in which three key, undeniably life-like chemical disequilibria are ‘abiotically’ generated and maintained. If it proves not to be possible to experimentally substantiate these conjectures, then we may expect interest in the theory to wane.” Furthermore, falsifiable predictions of AVT were listed in Russell that would, if demonstrated, “reveal embarrassing missing links, or even leave the AVT as just one more casualty of the general theory of natural rejection.” We look forward to similar commitment and clarity from the wet-dry polymerizing pond people. However, we do admit to being impressed over the one prediction made by this group—viz., Dimitar Sassalov’s promise that Harvard University “will soon have the equivalent of a living thing in the lab at the chemical level”. We will be particularly interested to hear what bearing such an artifact might have on the putative ‘first universal ancestor’, its evolving progeny and the geochemical/geophysical disequilibria responsible for its emergence?

The “Water Problem”(sic), the Illusory Pond and Life’s Submarine Emergence—A Review (Russell, 2021)

pretty princesses

this isn't related to cephalopods at all, but re: bilateral symmetry, there's actually some fairly recent (like, last 15 years) evidence that cnidarians actually evolved from bilaterally symmetric ancestors! Contrary to popular belief, a lot of sea anemones and coral polyps, though externally radial, actually have a bilateral digestive system. This could be a case of convergent evolution, but what's really remarkable is that embryonically, cnidarians develop this bilateral symmetry the same way as bilaterians, *using the same regulatory genetic pathways*! The polyp body plan is considered to be the ancestral state for cnidarians, while the "simplified" swimming jellyfish body plan probably is a secondary development, as suggested by the cnidarian fossil record and evidence of loss of body patterning genes in jellyfish. Together, this suggests the really exciting hypothesis that bilateral symmetry is actually the original ancestral state for the common ancestor of cnidarians and bilaterians, and rather than bilaterians being the ones who made the innovation of bilateral symmetry from radial, cnidarians would be the group that altered their symmetry instead! Sources: 1, 2, 3

(Echinoderms like starfish also are secondarily radial; they have bilateral larvae who undergo a very weird metamorphosis into their pentaradial adult form. Search "brachiolaria", "pluteus larva", or "auricularia larva" for pics!)

It's also a common misconception that cnidarians don't have central nervous systems. They're often said to have merely diffuse "nerve nets," and they do, but they also have a condensed ring-shaped nerve that integrates signals from across the body, basically constituting a central nervous system in all respects besides not actually having a singular "brain". In particular, there's been a lot of research into the nervous systems of box jellyfish, which are probably the most specialized among cnidarians due to their unique possession of true image-forming eyes, which they use for navigating both long and short distances as well detecting prey. One study from just last year even found evidence that box jellies display associative learning! Sources: 1, 2, 3, 4

(I believe there's also been research into the learning capabilities of echinoderms but I'm not as familiar with the literature. I know starfish do actually have image-forming eyes on their arms, which at least one species uses to navigate, though they also definitely do a lot of smelling and stuff as well. Source: 1)

Imagine yourself submerged in the prehistoric ocean. There are no fish, instead the only life forms consist of feather-like sessile organisms that sit on the seabed, filtering the current. The early organisms that evolved out of this, such as Jellyfish and Starfish, had radial anatomy. Their body structure entails a central axis from which you can split everything else. These bodies are simple, not designed for active mobility, lacking a ‘forwards’ or ‘backwards’. They didn’t even have eyes, instead interacting with and responding to the world via photoreceptive cells. What emerged from this were two developments: the evolution of complex eyes and the emergence of bilateral anatomy in early vertebrates and arthropods. In contrast to radial anatomy, bilateral anatomy entails an organism that can be split down the middle with rough symmetry. This is to say that they are built for direction. A body that is built for mobility entails significantly more complex behaviour behind its operation. Behaviour, in this sense, also becomes significantly more directed. These creatures now living in the ocean or on the sea-floor now begin to directly interact with one another. The mechanisms facilitating this interaction become pretty apparent in the fossil record; eyes, claws and antennae. The evolutionary consequences of this are the emergence of a complex nervous system alongside the presence of predation and, as Godfrey-Smith puts it “[From this point on] The mind evolved in response to other minds”. 

Did you know blowfly larvae living in carcasses leave behind chemical cues which they actively seek out in order to aggregate in large groups, even with other species 😃 (source 1, 2)

^ my decomposing corpse lying out in the middle of the wilderness talking to the crows

I like making bets about things that happen in the far future and being like “if I’m wrong you can bring me back from the dead and say I told you so”, except haha sucker I’ll be long-eaten by flies by then, and those flies will have been eaten by toads and those toads will have been eaten by more flies; can’t bring me back when my atoms are already recycled and scattered all across the web of life, feeding and being fed upon, fluttering through countless existences before inevitably moving on; how many lives I have lived, how many lands my substance has visited, I am in the air and the water and the rock, how can you bring me back when I am already here

if you do bring manage to bring me back though you’ll have to also bring back a bunch of flies and toads and stuff so have fun with those