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Vernacular clarification about "brain" vs ganglion and other findings in research

Discussion in 'Tarantula Chat' started by Foxobot, Oct 11, 2018.

  1. Foxobot

    Foxobot Arachnopeon Active Member

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    So this thread was brought about as I was in my car thinking about all the replies I have gotten from my first post that there was alot of disagreement on. That thread went into several directions from my main question so I'm expecting this one to do the same and am posting in chat. However, it says in the description of chat that it is fun and casual, Is personal inconclusive research fun? Casual? Debatable. Haha. I don't mind if it is moved by admin. I will lay out my thought pattern and the things I found online from sources such as books to scholarly articles of research and even the Encyclopedia Britannica online. This will be lengthy and I encourage people not to just hit the disagree button because I won't know which section you specifically disagree with or why. I cannot claim these sources are correct, because I am a skeptic not cynical, I am just gathering them and hoping correction to what I find will be made or clarified. So let's start from the beginning, I will put my thoughts about each thing I find and what lead me to other areas. And I hope I make it clear enough to follow. Some of these topics I have set aside for now to come to my ultimate question of the night which regards the title.

    So I was driving home and thought about stress to a Tarantula and if it was part of the nervous system or a higher response of emotion that most claim isn't possible, I refreshed my knowledge from the information on these forums on all the listed behaviors of a stressed tarantula and decided to start with looking where stress is derived in humans because Google loves giving information as it pertains to humans first. And in my finding from Harvard health, it says this about where the stress response comes from and what it activates,
    "After the amygdala sends a distress signal, the hypothalamus activates the sympathetic nervous system by sending signals through the autonomic nerves to the adrenal glands. These glands respond by pumping the hormone epinephrine (also known as adrenaline) into the bloodstream." Here's the link:
    https://www.health.harvard.edu/staying-healthy/understanding-the-stress-response

    Okay Harvard, so it is the nervous system and tarantulas have one so they may have stress in a way humans relate to. Probably isn't some higher emotional thing but just nerve response. Okay so that leads me to think about the structures of anatomy for a tarantula, like they may truly have stress but how does their body process it? In my last thread it was quite a mass of opinions where one commenter said the tarantula does not have a brain but they have a ganglion and people agreed with them. Now I have looked on these forums and there's even posts from back in 2007 where commenters said a ganglion is a type of simplified brain in regards to if tarantulas have them. (Btw that topic lead to pain recognition and intelligence eventually, not staying on what a brain is) So in my first thread I was told I was really, let's say, ignorant. Which I never claimed to know any more than anyone, but I am willing to do the research for even the smallest things. Hense why we are here. So I decided to look up if spiders don't have brains then how their body process stress, like if they even have a hypothalamus or an adrenal gland or another structure that processes stress. I didnt find much, but I know the information may be out there but buried under Google ads and unrelated links. So I decided to instead look up if they had epinephrine, which if you remember Harvard said humans do, which would support more of a theory they have some kind of structure in their organs for stress response. And I came across this scholarly research article:
    MONOAMINES IN THE BRAIN OF TARANTULAS
    (APHONOPELMA HENTZI) (ARANEAE, THERAPHOSIDAE):
    DIFFERENCES ASSOCIATED WITH MALE
    AGONISTIC INTERACTIONS
    It was in PDF format so I don't have a link for it but you guys can Google it, it is interesting. This is the first part of the abstract:
    "Experiments were conducted to determine the effects of male-male agonistic encounters
    on changes in monoamine neurotransmitter concentrations in the supraesophageal ganglion (brain) of the
    tarantula, Aphonopelma hentzi."
    I read the entire study because it was interesting and one thing they did measure in their experiment was change in epinephrine. So it did conclude they for one have it. So okay that is cool, getting somewhere, but whoa, wait. Did they just say the ganglion was a brain? This is where that little skeptical part of me starts to fire.
    So obviously I got too distracted by that to continue to look into what exactly controls the stress response. Don't worry I will get back to that later in time because now I feel something isn't justified. And yeah all of this is a lead-on to the main topic (as title suggests) for people reading who are wanting me to get to the point, haha sorry, it's coming I swear!
    So now I look into is the ganglion technically a type of brain. To clarify I don't mean by measures of intelligence or anything the 2007 thread on these forums mentioned. I mean just as a tarantula has a leg, it may look very different from other legs and technically function differently, but it is still considered a leg. So I get to googling. And I find this from the Encyclopedia Britannica:
    "The nervous system of spiders, unlike that of other arachnids, is completely concentrated in the cephalothorax. The masses of nervous tissue (ganglia) are fused with a ganglion found under the esophagus and below and behind the brain. The shape of the brain, or epipharyngeal ganglion, somewhat reflects the habits of the spider;" here's the link:
    https://www.britannica.com/animal/spider-arachnid/Nervous-system-and-senses

    Okay so even the Encyclopedia Britannica suggests it is a type of brain, but feel that? It's my skeptical mind saying "but what if we can't trust the Encyclopedia Britannica?" Sigh okay we will look more, but first I'm going to finish reading this because it is also pretty interesting. And if you guys want to look through it, it has way more information like functions like nerve stimulation and even digestion.

    So as I look for more information about the ganglion I find this book:
    The Tarantula Keeper's Guide: Comprehensive Information on Care, Housing...
    By Stanley A. Schultz, Marguerite J. Schultz
    Here's a link to the preview of the book from Google:
    https://books.google.com/books?id=rIVAkA3IlHgC&pg=PA45&lpg=PA45&dq=tarantula+hypothalamus&source=bl&ots=YaszFeXUym&sig=3Y4_DknYQmnhl7F8aFap56DMJyU&hl=en&sa=X&ved=2ahUKEwisy-mKpP_dAhUQ0lMKHUCwBJEQ6AEwAHoECAAQAQ#v=onepage&q=tarantula hypothalamus&f=false

    So for the first thing I saw about this book was the part on the nervous system and hey it mentioned our hypothalamus! Sweet! It says they have a radiating array of nerve fibers originating from a brain and that it exists in two portions, a supraesophageal ganglion and a subesophageal ganglion. And it goes on to discuss the functions of both parts. Very informative but also says the structure is a brain.
    PicsArt_10-11-08.07.50.jpg
    So I am scrolling through this book and it seems like a really neat book, even has emergency procedures a tarantula owner should take if they notice bad signs and how to recognize them.
    But then I come across a tiny section as I'm scanning through it, so let me painfully switch back and forth to type it out because this part may stir up some heat ->that I'm not going to argue here<- , but if you were on my first thread you may start shaking your head. Honestly I dont want to stir up because I know now it is SENSITIVE, but I've seen it from a professional source and I'm going to at least share and move on to the rest of tonight's findings with you guys. So here it is straight from the book and hold on to your britches, "Although several groups of spiders seem to be able to form images and derive useful information from their eyes, it is not known as to what extent tarantulas possess that capability. However, wild tarantulas, or those not accustomed to handling, do react to motions around them." It goes on to explain their fight and flight and what is known they can perceive. You may have missed what I read in this: "those not accustomed to handling". To me this seems like the authors are inferring that they believe some tarantulas are accustomed and some are not.
    Snapchat-1208767565.jpg
    WHOA LOWER THE WEAPONS. As a disclaimer, I do not encourage or condemn handling. I am just showing what I find. You, the reader, may understand why I'm tiptoeing through this if you read my last thread. Handling as a whole is strongly not recommended on these forums. Moving on!

    Okay the last part of the book I noticed that I found interesting was talking about the vernacular term for a baby spider or young spider spiderling, also known as sling, to not be an officially sanctioned term for a wee one. This may have changed because the book was published in 2009. But if you know you can share the knowledge.
    PicsArt_10-11-10.00.19.jpg
    You may think, so what? Well this is part of my findings hang in there.

    So I think, okay the forums aren't going to like part of what I found there so maybe I need a more general ruling from so many sources that we have condensed in one place. Sound familiar? Yep heading to Wikipedia! Not everything in Wikipedia is going to be accurate, they try to moderate but there's always that guy(or gal) who thinks it's funny to change it or add unsupported things. But here we go! First let's Google ganglion. My first result was about ganglion cysts. Oh my! No no no no no. Not what I'm looking for. So let's go to brain wiki first scan it, and then to the ganglion one. And again here you are:
    https://en.m.wikipedia.org/wiki/Brain
    And what do we see? A big beautiful heap of information! So let's scroll down and I'll point some things out:
    "Except for a few primitive organisms such as sponges (which have no nervous system)[13] and cnidarians (which have a nervous system consisting of a diffuse nerve net[13]), all living multicellular animals are bilaterians, meaning animals with a bilaterally symmetric body shape"
    okay why did I post this? Because you may not know what a bilaterial is. So they go on to say:
    "At a schematic level, that basic worm-shape continues to be reflected in the body and nervous system architecture of all modern bilaterians, including vertebrates.[15] The fundamental bilateral body form is a tube with a hollow gut cavity running from the mouth to the anus, and a nerve cord with an enlargement (a ganglion) for each body segment, with an especially large ganglion at the front, called the brain. The brain is small and simple in some species, such as nematode worms; in other species, including vertebrates, it is the most complex organ in the body." So that says all bilaterals have certain structures in common, but a strong note is they note a ganglion as being a brain. And to scroll a bit further to see what they regard as exceptions "There are a few types of existing bilaterians that lack a recognizable brain, including echinoderms and tunicates. It has not been definitively established whether the existence of these brainless species indicates that the earliest bilaterians lacked a brain, or whether their ancestors evolved in a way that led to the disappearance of a previously existing brain structure." Okay well spiders aren't in those. And here is the last section I will look at for now on this page: "Two groups of invertebrates have notably complex brains: arthropods (insects, crustaceans, arachnids, and others), and cephalopods (octopuses, squids, and similar molluscs).[18] The brains of arthropods and cephalopods arise from twin parallel nerve cords that extend through the body of the animal. Arthropods have a central brain, the supraesophageal ganglion, with three divisions and large optical lobesbehind each eye for visual processing." And that concludes that wikipedia considers tarantula ganglion as a form of a brain. But just real quick I'll click the link for ganglion and bring this up, "Ganglia provide relay points and intermediary connections between different neurological structures in the body, such as the peripheral and central nervous systems". Okay so the ganglia kind of functions like a most condensed basic form of a brain. Alright. So if you made it this far look how long that took? I can assure you I've been on this for over 7 hours. So why did I do all this? Because I have no life? Hey be nice! Shhh. Well I did it because I got conflicting information. I want to be overly detailed because I dont want anyone to think some of the things I have found is baseless arguing. So if you made it this far, can we as a community agree that they do have a brain even if it is a different form? Or can I influence people to agree that it is an acceptable vernacular term? I mentioned earlier how the slings vernacular term would be relevant so here it is now, even though sling is not an officially sanctioned term, this community does not seem opposed to using it to regard a spiderling. So is brain an acceptable vernacular term for the ganglion the tarantula has? Please don't just hit the disagree button because I won't know which part you are disagreeing with. I would much prefer a comment and maybe information that is hopefully linked to look further into. So I did all this to be more correct with a vernacular term? Uh.... >.> ... yes.:writer:
     
    Last edited: Oct 12, 2018
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  2. boina

    boina Lady of the mites Arachnosupporter

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    Uh-oh.

    First of all, please, please, please, don't cite the Tarantula Keepers Guide as a scientific source. It isn't. It wasn't written by a scientist and it contains quite a few things that are very obviously wrong or highly unscientific, among all the good and right things. It is certainly not a source to clear up any grey areas.

    Second, a brain is what you call a brain. I don't think there is any clear scientific separation of brain and ganglion. I'm not even sure this is a point worth discussing. I think people insist it's a ganglion to make it clear that they do not consider it equivalent to a vertebrate brain.

    And yes, the invertebrate brain or ganglion has a lot more similarity with a vertebrate brain on a molecular level than people give it credit for, especially on this forum. Invertebrate brains are used as model organisms to study the genetics and molecular biology of memory because it seems to be identical in all animals, vertebrate and invertebrate. Of course, invertebrates feel fear, or an eqivalent thereof, because that's needed for basic survival - the genetics of fear responses have been studied in flies, after all. I'm sure there is also a stress response in invertebrates. Unfortunately, few studies have ever been done on tarantulas. They just don't make good laboratory animals, they grow too slowly and show too little measurable reactions.

    Yes, the invertebrate brain is much more similar to the invertebrate brain than people want to believe, but that doesn't mean a tarantula feels things just the way a puppy or a human does...

    Unfortunately that's the point: If you state that tarantulas can learn, and even have feelings in a way (fear, stress), things that can be easily deduced from proven facts about invertebrates, people will put you in the 'esoteric' bracket and never let you out again. And it really is a problem: how can you stay rational and still acknowledge that the tarantula brain is actually a brain, capable to do more things than just instinctual reactions, without getting all like 'oh my tarantula loves me' like.

    People around here tend to shoot down every mention of tarantula learning, intelligence, feeling and so on to avoid the anthropomorphizing, overly emotional crowd. And I can understand them - I stopped doing research in animal behaviour because I was so sick and tired of people ruining every experiment with 'oh, how cute!' and 'that dog must be so sad' and 'my dog did that, too, once...'. For some reason it seems to be impossible to talk about brain functions in a rational, detached, scientific way.

    Or even talk about what a brain is and what it isn't.
     
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  3. Foxobot

    Foxobot Arachnopeon Active Member

    I don't know much about the book, which is why I gave multiple sources, haha even questioning the Encyclopedia Britannica (some scientist like it, some don't) and stated at the beginning that some sources may not be held in high regards. The book may have some good information in it that they got from credible sources, so I mentioned it anyways. It was part of the findings for tonight and can even be entirely ommited and not effect the discussion for people who don't agree with parts of the book.

    I want to find what is technically true. If you're worried about what people interpret it as, I can't really help that. I don't think it is a good thing to alter technically true information just so people don't get the wrong impression. Remember the fuss about Pluto not being a planet? oh man. But, if it is a brain then it should be acceptable to call it a brain.

    The point of this was the vernacular terminology being accepted.

    If some people want to shut out any research that even hints to anthropomorphizing, they aren't encouraging research and are kind of the opposite end of the spectrum from the overly emotional. So I guess you could kind of say they are like the robot supporters. I mean for me they are just as problematic to research as the overly emotional. It kind of feels like any two party politics where people at each end are so concerned by what they think they hurt research. I am somewhere in the middle with just about everything because I am a skeptic. Being a skeptic I look for truth.

    I don't think hiding or abandoning research is going to help the problem, so no matter what side you are on (you don't have to say), I say still continue research you have time for and that interests you and post them for people to squabble about. They may even try to prove you wrong, and two things can happen when people get heated: they provide you with more information, which all is helpful for research, or they may learn something and hopefully question their beliefs to form the most unbias opinions they can.
     
  4. boina

    boina Lady of the mites Arachnosupporter

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    I think there is a misunderstanding here. I wasn't talking about research as a hobby I was talking about research in a university setting and being paid for it. You come over as pretty patronizing in this paragraph. I may just mention that I'm not some 15 year old that needs advice on how to conduct herself in life - not that I'd even talk to 15 year olds the way you do here.

    Since I really dislike being patronized I'll see myself out.

    Oh, and before I go:

    That's a extremely unscientific statement. And I thought I was making myself clearer than I did, obviously.
     
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  5. Foxobot

    Foxobot Arachnopeon Active Member

    It wasn't my intention to be patronizing. I read your post as genuine. I didn't mean you hiding, I meant people hiding their finding because of what you said about fear of others putting them in esoteric brackets.
    And I encourage you to continue your research because you said you quit because of people misinterpreting it and jumping to conclusions. I meant research in general whether professional study or people in search of it. I don't know what I said to upset you?
     
  6. boina

    boina Lady of the mites Arachnosupporter

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    I quit that research over 20 years ago. So you encourage me to quit my job in a different science and go back to a type of research I abbandoned a lifetime ago? You assume too much. Get facts first before you 'encourage' anyone to do anything, or, to put it bluntly: you are in no position to 'encourage' me what to do with my life.
     
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  7. Foxobot

    Foxobot Arachnopeon Active Member

    :eek: Lady I don't even know who you are! I didn't assume your profession, age, or anything. The only thing I know about you is your tag says you are a lady of mites. So I'll call you a lady but for all I know you could be a man? You don't know me either. I'd encourage anyone to do research in what interest them in general despite negativity, even if its outside of their career in their free time and just as a hobby. Did I post this in the wrong thread or something? I thought this was in chat for everyone?
     
  8. fleetwoodmcc

    fleetwoodmcc Arachnopeon

    r/iamverysmart
     
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  9. Foxobot

    Foxobot Arachnopeon Active Member

    haha I didn't mean to come off that way. I have had so many people already misinterpret and yell at me in other threads, so I am trying to be as clear as possible in this one and show that I have a base for my argument. In all the information I found I still like looking at all the pictures. :smuggrin:
     
  10. viper69

    viper69 ArachnoGod Old Timer

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    As you know it depends on the context. No one calls a human brain, a ganglion. In human biology there is a clear separation. ;)


    @Foxobot Ganglia are not brains this is a fact, not an opinion. No scientist or neurologist would say you have ganglia between your ears.

    Many definition skimmed from the web are often in the context of humans.

    However as you have seen, when you drop down to "lower" animals, ganglia and brain gets muddied. The fact is, spiders don't have a brain, they have ganglia.
     
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  11. Foxobot

    Foxobot Arachnopeon Active Member

    Oh man. Now I'm even more confused. I tried to take it as in context of spiders. If it truly isn't a form of a brain then why are so many sources listing it as one? In terms of a computer, the CPU acts like a brain, but obviously isn't and isn't further called brain in the rest of the context, so why are all these sources not making the clear distinction and dropping calling a ganglion a brain?
     
  12. boina

    boina Lady of the mites Arachnosupporter

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    Ok. Give me a definition. Because a lot of invertebrate scientist do seem to call it a brain. But don't get me wrong I'm not insisting on calling it one, I just can't find a clear definition of what is what.
     
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  13. Foxobot

    Foxobot Arachnopeon Active Member

    You are much better at this than I am. This is exactly what I want to know too! But I don't know how to say it online in a way people don't think I'm trying to argue or talk down to them. :oops:
     
  14. viper69

    viper69 ArachnoGod Old Timer

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    Invert scientists call it a brain merely as human convention IMO
     
  15. viper69

    viper69 ArachnoGod Old Timer

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    Cant speak for other authors. It is easier to refer to it as brain, brain conjures up very specific ideas for people, different than ganglia.

    It’s a form of brain, but not a brain.

    Brain is a complex organ. Ganglia are clusters of nerves cells. Case closed.
     
  16. Foxobot

    Foxobot Arachnopeon Active Member

    Hmm. Would you say it's like the idea of how much can you strip from a car before it is no longer a car? If that's the case, I don't know if this can be definitively answered.
     
  17. viper69

    viper69 ArachnoGod Old Timer

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    I wouldn't say that at all. When you strip a taillight from a car, the light isn't called a car. And the car is still a car, but has a piece missing. This idea cannot be applied to ganglia as "it's a brain but with a lot of pieces of missing".

    I'm not sure what you are trying to determine anymore. Ganglia are not brains. They may serve as a brain, but not a brain as found in many other types of animals, they are merely a cluster of neurons.

    I'm not sure why the above facts aren't sufficient. Good luck.
     
    Last edited: Oct 14, 2018
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  18. MintyWood826

    MintyWood826 Arachnoknight Active Member

    To me that says that it's a brain, albeit simpler...so I'm confused...
     
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  19. viper69

    viper69 ArachnoGod Old Timer

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    I can't help that. I'm far too busy to list it all out. If you are really interested, see below ;)

    https://www.ncbi.nlm.nih.gov/pubmed/12523550
     
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  20. Foxobot

    Foxobot Arachnopeon Active Member

    ooooh. gotcha! So an invertebrate ganglion isn't a brain but parallel evolution (I suppose?) to help accomplish some of the same goals for the animal. I wish all these sources would stop calling it a brain then. :shifty: