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'Zombie ant' brains left intact by fungal parasite

phys.org

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Re: 'Zombie ant' brains left intact by fungal parasite

#61

Post by ConceptJunkie »

deadmetheny wrote: post #42
Larrikin wrote: post #24

Earlier quoted context omitted.

I was always a little disappointed I had so many friends get into Harry Potter when I was younger. Animorphs explores this idea in depth, especially for a kids novel. So in depth that you eventually feel that the parasite controlling other beings can be justified in their war. It is still a kids series so many of the books are filler, but the beginnings, chronicles, and ending are very deep even when looked at throug…

>It is still a kids series Man, after having gone back and re-read them as an adult, it's only barely a kids series. Animorphs went hard in the paint with the horrors of war angle.

Any good media "for children" can be enjoyed by adults. I never read Animorphs, or Harry Potter, for that matter, but there are good analogs on TV: Adventure Time and Gravity Falls, both of which are cartoons for children, but have depth and sophistication that adults can appreciate while still being accessible to children.

Another good example is Terry Pratchett's kid-oriented books (e.g., the Tiffany Aching Discworld books, the Johnny books and the Bromeliad trilogy). He never wrote down to children. These books weren't really much different from his other books for an adult audience, although the plots were simpler, tended to focus more on children characters, and the morality was less ambiguous (as it can be in real life)). But as a big fan of Pratchett, I enjoyed these "children's" books no less than the others.

Re: 'Zombie ant' brains left intact by fungal parasite

#62

Post by ConceptJunkie »

TheCoreh wrote: post #8
zaarn wrote: post #2

>"Normally in animals, behavior is controlled by the brain sending signals to the muscles, but our results suggest that the parasite is controlling host behavior peripherally," Hughes said. "Almost like a puppeteer pulls the strings to make a marionette move, the fungus controls the ant's muscles to manipulate the host's legs and mandibles." Probably the most "And I Must Scream" moment in mother nature. Imagine a hum…

Wouldn't that require the fungus to have a nervous system of its own?

No more than the genes that lead animals to survive because they have an instinct to hide from predators.

These evolutionary processes do not imply any kind of intent. They exist because they work. The things that don't work eventually disappear.

Re: 'Zombie ant' brains left intact by fungal parasite

#63

Post by ConceptJunkie »

macdust wrote: post #51
46886532558 wrote: post #45

Earlier quoted context omitted.

I don't think partial control of a complex system requires a system of equal complexity. Even human behavior can be influenced in the brain by something simple as a drug or virus.

Specific directives (to find a suitable place to anchor itself) require awareness of the terrain and object-recognition. Either a) the fungus has stumbled upon the signals to accomplish this singular feat or b) the fungus can read the ant's perceptions and can navigate. Finding the signal seems more likely because it is much less complex an achievement.

Or the fungus "stumbled" across an effect on the ants' nervous system that was beneficial to it, so it thrived.

Emergent properties don't require sophistication. They arise despite the lack of sophistication or the ability for specific intent. That's the definition of "emergent".

Re: 'Zombie ant' brains left intact by fungal parasite

#64

Post by gumby »

pavement wrote: post #58
gumby wrote: post #56

Earlier quoted context omitted.

> One conceptual reality to consider is that the ants on the surface of any hill are not quite as sentient as the queen... The term "queen" is a misnomer. She is the ovulation organ of the hive, nothing more. Yes, she has many solicitous "attendants" but then again I too am more attentive to my own generative organs than I am to my other ones. In fact she has less will than any of the mobile ants and bees. Like the C…

One, then, is left to wonder where the seat of organizational sentience really resides, if it resides in any of the independent organisms at all. Ants surely seem sentient, even if still lower-order animals. Is it just an emergent detail of aggregate reflexive behavior across all members? How (and why) would soldiers know to build a bridge with their bodies, to cross a water barrier, seemingly from birth? Maybe the l…

Why can't it be an emergent phenomenon? "You" are just a huge collection of independent organisms, a large subset of which share the same genetic material. But given the degree to which your various symbiotes and parasites (in your gut, in the biofilms in your sinuses, etc) excrete hormones, and the huge quantities of neurotransmitters emitted and received wholly inside your gut, it seems a Victorian concept like "seat of organizational sentience" is rather obsolete.

As for sentience itself...it's pretty clear (even from timing data alone) that we end up confabulating most of what we consider perception of reality, so perhaps consciousness and sentience are just convenient mechanisms to characterize the order of events?

Re: 'Zombie ant' brains left intact by fungal parasite

#65

Post by pavement »

mikeash wrote: post #60
pavement wrote: post #58

Earlier quoted context omitted.

One, then, is left to wonder where the seat of organizational sentience really resides, if it resides in any of the independent organisms at all. Ants surely seem sentient, even if still lower-order animals. Is it just an emergent detail of aggregate reflexive behavior across all members? How (and why) would soldiers know to build a bridge with their bodies, to cross a water barrier, seemingly from birth? Maybe the l…

Which cell of your brain is the seat of sentience? I know little about ants and maybe that analogy sucks, but it seems like it could easily not be anything more specific than the colony as a whole.

Well, we have clues that it exists above the chemical layer, and above the cellular layer, since any individual person is capable of sensory processing at a fidelity measurable to auditory sample rates beyond tens of thousands of cycles per second, and visual frame rates above 30 before we notice flicker. That tells you that a continuous signal is captured and integrated across the organ (the brain) in real time.

Re: 'Zombie ant' brains left intact by fungal parasite

#66

Post by User23 »

openasocket wrote: post #33
zaarn wrote: post #2

>"Normally in animals, behavior is controlled by the brain sending signals to the muscles, but our results suggest that the parasite is controlling host behavior peripherally," Hughes said. "Almost like a puppeteer pulls the strings to make a marionette move, the fungus controls the ant's muscles to manipulate the host's legs and mandibles." Probably the most "And I Must Scream" moment in mother nature. Imagine a hum…

I had another thought which might be even more terrifying. I couldn't find anything suggesting the fungus cuts off or disrupts the ant's actual nerve endings, and from video you can see towards the end that the ant moves in an unnatural, jerky way, not like a normal ant. This could be just because a fungus is bad at acting like an ant, but what if it's also because the ant is actively trying to fight it ?! I don't th…

"the fungus requires use of the ant's nervous system and sensory processing to figure out where a high up place is" How do you know this?

Re: 'Zombie ant' brains left intact by fungal parasite

#67

Post by Sniffnoy »

It has to be getting sensory input, though, right? So it must be reading that out of the brain somehow even if it's not controlling the brain, right? Or no?

Wondering now how ants walk and climb and such -- it would seem easier to go for the brain if you need to effect complex behaviors like that. But I recall that with insects' wings, at least, the brain only needs to send one signal and they'll beat for a long time. So maybe such behaviors are stored down by the legs or whatever, and that's why it doesn't need to go for the brain?

Re: 'Zombie ant' brains left intact by fungal parasite

#68

Post by burntrelish1273 »

More "zombie" (behavior-altering) parasites:

https://www.damninteresting.com/nugget/mind-controlling-wasp...

https://www.damninteresting.com/nugget/body-snatching-barnac...

https://en.wikipedia.org/wiki/Behavior-altering_parasite

Also rabies and toxoplasmosis.

Re: 'Zombie ant' brains left intact by fungal parasite

#69

Post by deadmetheny »

ConceptJunkie wrote: post #61
deadmetheny wrote: post #42

Earlier quoted context omitted.

>It is still a kids series Man, after having gone back and re-read them as an adult, it's only barely a kids series. Animorphs went hard in the paint with the horrors of war angle.

Any good media "for children" can be enjoyed by adults. I never read Animorphs, or Harry Potter, for that matter, but there are good analogs on TV: Adventure Time and Gravity Falls, both of which are cartoons for children, but have depth and sophistication that adults can appreciate while still being accessible to children. Another good example is Terry Pratchett's kid-oriented books (e.g., the Tiffany Aching Discwor…

> I never read Animorphs

There is a scene in one of the books where the narrator finds a sliver of flesh still stuck in his teeth from when he was fighting in tiger form, and that isn't a particularly gruesome scene in comparison to the rest of the books, just to be clear. Harry Potter's later installments come close but Gravity Falls and Adventure Time aren't even in the same league. I do absolutely agree with your basic point though - I also greatly enjoy all of these series watching or reading them with younger family members.

Re: 'Zombie ant' brains left intact by fungal parasite

#70

Post by titzer »

pavement wrote: post #40
openasocket wrote: post #33

Earlier quoted context omitted.

I had another thought which might be even more terrifying. I couldn't find anything suggesting the fungus cuts off or disrupts the ant's actual nerve endings, and from video you can see towards the end that the ant moves in an unnatural, jerky way, not like a normal ant. This could be just because a fungus is bad at acting like an ant, but what if it's also because the ant is actively trying to fight it ?! I don't th…

One conceptual reality to consider is that the ants on the surface of any hill are not quite as sentient as the queen. The survival of a queen that produces viable progeny is paramount to the survival of the species and, at a more granular level, the bloodline of the individual colony. The queen is dependent on the drones being as obedient as your fingers and tongue might be to your brain, with your brain being the q…

> The colony is really the organism, and the soldiers serve it, abiding by prevailing odors, likely without very much free will. Or at least as much free will as your arm has, to reflexively recoil from a burn, or lash out at some unassessed threat when reacting in fear.

Yep. And now go up a level. What are _you_ in the organism that is humanity? That concept is worth a lifetime of thought as you go about your job, consuming resources and processing information that is given to you to process.

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