Tliltocatl vagans Behavioral Study

[SpookySpooder]

https://www.scielo.org.mx/pdf/azm/v28n1/v28n1a1.pdf

So I'm curious what you all make of this...

One question that's prominent in my mind is how are they sensing the silk, is it through touch? Do they have the sensation to differentiate between ground and silk?
Is it sight? Can they see the silk? Are they tasting it? Smelling it?

Perhaps someone more knowledgeable about Tarantulas than myself might know?
@viper69 @l4nsky @AphonopelmaTX

Thanks in advance for your insight.

 

[A guy]

They can definitely sense the silk by touch, they have chemoreceptors on the legs to differentiate different types of surfaces and objects.

I've read in a book that slings will stick together up to a certain size. I think that's what's happening here

 

[LucN]

They can definitely sense the silk by touch, they have chemoreceptors on the legs to differentiate different types of surfaces and objects.

I've read in a book that slings will stick together up to a certain size. I think that's what's happening here

I want to say that book is probably Tarantulas of Belize by Steven B. Reichling. I definitely recall such an observation in it with local T. vagans. Yes, they. sense the silk by touch and the chemoreceptors probably help in that regard too. There's strength in numbers, if they huddle so close together, there's better chances some will survive predation rather than risking the early journey solo. Very cool pic from 2005. Blows my mind how tiny they are at that size and eventually grow to be 5"+ adults.

 

[Ultum4Spiderz]

I want to say that book is probably Tarantulas of Belize by Steven B. Reichling. I definitely recall such an observation in it with local T. vagans. Yes, they. sense the silk by touch and the chemoreceptors probably help in that regard too. There's strength in numbers, if they huddle so close together, there's better chances some will survive predation rather than risking the early journey solo. Very cool pic from 2005. Blows my mind how tiny they are at that size and eventually grow to be 5"+ adults.

Pokies have been spotted together in the wild although I haven’t seen the pictures or proof and the chicken spider people were talking about. That vanished from popularity because it’s not in the hobby or anything here. One year it was cool then crickets.

 

[viper69]

View attachment 466293

https://www.scielo.org.mx/pdf/azm/v28n1/v28n1a1.pdf

So I'm curious what you all make of this...

One question that's prominent in my mind is how are they sensing the silk, is it through touch? Do they have the sensation to differentiate between ground and silk?
Is it sight? Can they see the silk? Are they tasting it? Smelling it?

Perhaps someone more knowledgeable about Tarantulas than myself might know?
@viper69 @l4nsky @AphonopelmaTX

Thanks in advance for your insight.

Authors didn't observe silk in that pic.

They can't see it if at all.

Easily could be by touch, and no doubt difference between ground/silk IMO As for the rest, I don't know, and neither does science yet.

Rick West ( @Rick_C_West ) authored a paper on T dispersal as well. I might be able to find it, but I'm not sure I can.

 

[SpookySpooder]

Authors didn't observe silk in that pic.

They can't see it if at all.

Easily could be by touch, and no doubt difference between ground/silk IMO As for the rest, I don't know, and neither does science yet.

Rick West ( @Rick_C_West ) authored a paper on T dispersal as well. I might be able to find it, but I'm not sure I can.

Did you mean this?

https://www.researchgate.net/profile/Rick-West-2/publication/305399122_Brachypelma_of_Mexico/links/578d17e708ae7a588ef3dcd5/Brachypelma-of-Mexico.pdf

Can you elaborate for me what you mean by touch? can they feel sensations through nerve endings like that? I am under the assumption that they can produce a pheromone trail from their spinnerets and that the T behind them can smell that with chemoreceptors on their toes or pedipalps.

 

[l4nsky]

I got nothing outside of previous converations we've had on the potential chemoreceptor hairs we've discussed in a prior thread lol. I haven't dove into dispersion as it doesn't really have an effect in captive reproduction, which has been the focus of my attention in recent years.

 

[AphonopelmaTX]

https://www.scielo.org.mx/pdf/azm/v28n1/v28n1a1.pdf

So I'm curious what you all make of this...

One question that's prominent in my mind is how are they sensing the silk, is it through touch? Do they have the sensation to differentiate between ground and silk?
Is it sight? Can they see the silk? Are they tasting it? Smelling it?

Your questions were answered twice in the text of the article; once in the introduction section and again in the discussion section. I'm not sure what more you need to know.

 

[Mustafa67]

https://www.scielo.org.mx/pdf/azm/v28n1/v28n1a1.pdf

So I'm curious what you all make of this...

One question that's prominent in my mind is how are they sensing the silk, is it through touch? Do they have the sensation to differentiate between ground and silk?
Is it sight? Can they see the silk? Are they tasting it? Smelling it?

Perhaps someone more knowledgeable about Tarantulas than myself might know?
@viper69 @l4nsky @AphonopelmaTX

Thanks in advance for your insight.

Absolutley LOVE this journal thank you for sharing it. Makes me want to buy a T Vagans now

 

[viper69]

Did you mean this?

https://www.researchgate.net/profile/Rick-West-2/publication/305399122_Brachypelma_of_Mexico/links/578d17e708ae7a588ef3dcd5/Brachypelma-of-Mexico.pdf

Can you elaborate for me what you mean by touch? can they feel sensations through nerve endings like that? I am under the assumption that they can produce a pheromone trail from their spinnerets and that the T behind them can smell that with chemoreceptors on their toes or pedipalps.

Not sure that’s the paper

Touch, yes with neurons hah.

 

[SpookySpooder]

Apologies to everybody if this is a repost of a previous conversation you've all had 10 years ago. I haven't been around that long so I definitely missed it. (But is it really so bad to revisit a topic with someone new? Are you that unwilling to teach me and help me learn?) If you don't want to discuss then you have that right and ability.
I will apologize for pinging you unnecessarily Aphonopelma, I won't do it again. I just thought I would ping people whom I've observed displaying deep wells of knowledge about Arachnid science and the hobby on this forum to expand my own knowledge of the subject.

To answer your question: I guess I got excited reading and learning about Tarantulas and just wanted to see what the more senior and knowledgeable members thought... also to make sure I correctly interpreted what I read. What I need more? I'm not quite sure myself.

My secondary goal was to potentially invoke some thoughts and musings and open a discussion to expand my understanding and knowledge of Tarantulas on the Tarantula forum...? I'm sure the bulk of the iceberg of Tarantula knowledge and experience is hidden deep within your brains, I can't just easily reach into there and read your thoughts.

Again, I'm sorry if I stepped on any of your many toes by pinging you to repetitive material.

I got nothing outside of previous converations we've had on the potential chemoreceptor hairs we've discussed in a prior thread lol. I haven't dove into dispersion as it doesn't really have an effect in captive reproduction, which has been the focus of my attention in recent years.

Thanks for your reply... so this brings up a question for me regarding captive reproduction as I'm aware you are heavily focused on the breeding aspect.

You don't need to answer it if it's an issue... really just ignore me if it annoys you as I am not trying to anger or upset anybody by simply asking questions.

When you say "it doesn't really have an effect in captive reproduction" can you elaborate what you mean? As in they slings do not need to stay around each other or with mom in order to develop fully? I understand that you can produce a sac with all surviving slings, but based on what I've read, my understanding is that we don't have a full conclusion as to the adaptive significance of this behaviour... And if I may ASSUME something, this suggests that socialization/learned behaviour may be more important to development and survival than we've yet to realize.

I formualated these ideas from reading another study done on Hogna carolinensis:
"Contact with maternal parent and siblings affects hunting behavior, learning, and central nervous system development in spiderlings of Hogna carolinensis"

Contact with maternal parent and siblings affects hunting behavior, learning, and central nervous system development in spiderlings of Hogna carolinensis (Araeneae: Lycosidae) - PubMed

The purpose of this study was to determine the effects of early experience (rearing conditions) on the central nervous system (CNS) and behavior of spiderlings of Hogna carolinensis (Lycosidae). We were interested in whether or not spiderlings that were allowed to remain in contact with their...

pubmed.ncbi.nlm.nih.gov

Please don't get super mad because I referenced another Arachnid, as I'm well aware I'm making a leap when comparing two different animals. I used this study to make an assumption and formulate a question in my head. Honestly asking a question like this would have been well-recieved back in my University days so I'm a bit confused and wary now.

If you think I'm woefully off base by comparing the two and making this assumption, then simply state that.

@everybody
I have to ask:
- Are Tarantulas so different that things that affect other related members of their family do not apply to them?
- Am I completely stupid for thinking that Tarantula slings would benefit in development and behavior from spending more time with their mothers?
- Why do Baboon species raise their young around their burrows if it was pointless?

I just got questions, man. They're all unanswered in my head.

 

[sparticus]

So from what I'm seeing this particular behavior seemed like it was related to the sling's dispersal stage, which is why I think Insky was saying it's not relevant to breeding, as most disperse the slings artificially to maximize survival rate. From what I have gathered, when we leave them all together it seems usually there will most likely be fewer successful slings, but the ones that do succeed may tend to be larger and heartier. I've only had one spider produce offspring in my care, a wild caught herpyllus ecclesiasticus, and I observed that she killed and webbed a prey item and left it near the egg sac, presumably as a first meal for the hatchlings. She would vigilantly guard the egg case until the slings eclosed (~2nd instar, maybe?) And then she would try to get away from them at top speed. Her instincts clearly said it was time to leave, maybe to avoid snacking on her own offspring? Anyway, there was clearly also some kind of signal to the babies that it was time to leave, because all the babies would suddenly leave the egg case over the course of a few hours in one day. This behavior seems to me to be in the same kind of direction. I assume after the dramatic "train" behavior they reach a certain distance from the nest or some other marker of a suitable location, spread out, and each starts to work on making homes for themselves. I'm also assuming if there are a bunch marching out together, the chances of predation for any one individual may be reduced.
As to why some species' slings may be raised to a larger size with the mother, I imagine there is variation between species on what approach is the most effective to maximize healthy sling survival rates. i.e. if small food is less plentiful in an area maybe keeping slings with mom until they are a bit bigger will allow them to eat off mom's larger kills and more will survive. Sorry if I'm misinterpreting your question here....

 

[SpookySpooder]

Thanks. I do understand what they're doing, I'm moreso interested in the how and the why.

It's an idea that grew into more questions, so I don't really have a singular question to be answered. I'm searching for information and insight.

I guess to put it short: another question I have is, "is it possible that extra time with mom can positively affect the development and behavior of slings in captivity? Are we (the hobby) depriving our newborn slings an aspect of their early development?"

Questions questions questions.

Thank you for your time and attention.

 

[LucN]

Thanks. I do understand what they're doing, I'm moreso interested in the how and the why.

It's an idea that grew into more questions, so I don't really have a singular question to be answered. I'm searching for information and insight.

I guess to put it short: another question I have is, "is it possible that extra time with mom can positively affect the development and behavior of slings in captivity? Are we (the hobby) depriving our newborn slings an aspect of their early development?"

Questions questions questions.

Thank you for your time and attention.

The short answer would be no. Spending extra time with mom would simply increase the chances of further cannibalism. No spider gets "gentler" because of the upbringing, so to speak. Whether they're born in the wild or in captivity, they remain wild and totally unpredictable. Some individuals will simply be more tolerant to our interactions than others. A "docile" spider can become defensive over time. There's even been cases that individuals change temperament radically from molt to molt. It's the luck of the draw in the end. Of course keeping interactions to a minimum will decrease an individual to suddenly feel threatened. I try my best to open my cages as gently as possible to avoid startling them too much. So far, they're very laid back and easy to work with.

 

[viper69]

Apologies to everybody if this is a repost of a previous conversation you've all had 10 years ago. I haven't been around that long so I definitely missed it. (But is it really so bad to revisit a topic with someone new? Are you that unwilling to teach me and help me learn?) If you don't want to discuss then you have that right and ability.
I will apologize for pinging you unnecessarily Aphonopelma, I won't do it again. I just thought I would ping people whom I've observed displaying deep wells of knowledge about Arachnid science and the hobby on this forum to expand my own knowledge of the subject.

To answer your question: I guess I got excited reading and learning about Tarantulas and just wanted to see what the more senior and knowledgeable members thought... also to make sure I correctly interpreted what I read. What I need more? I'm not quite sure myself.

My secondary goal was to potentially invoke some thoughts and musings and open a discussion to expand my understanding and knowledge of Tarantulas on the Tarantula forum...? I'm sure the bulk of the iceberg of Tarantula knowledge and experience is hidden deep within your brains, I can't just easily reach into there and read your thoughts.

Again, I'm sorry if I stepped on any of your many toes by pinging you to repetitive material.


Thanks for your reply... so this brings up a question for me regarding captive reproduction as I'm aware you are heavily focused on the breeding aspect.

You don't need to answer it if it's an issue... really just ignore me if it annoys you as I am not trying to anger or upset anybody by simply asking questions.

When you say "it doesn't really have an effect in captive reproduction" can you elaborate what you mean? As in they slings do not need to stay around each other or with mom in order to develop fully? I understand that you can produce a sac with all surviving slings, but based on what I've read, my understanding is that we don't have a full conclusion as to the adaptive significance of this behaviour... And if I may ASSUME something, this suggests that socialization/learned behaviour may be more important to development and survival than we've yet to realize.

I formualated these ideas from reading another study done on Hogna carolinensis:
"Contact with maternal parent and siblings affects hunting behavior, learning, and central nervous system development in spiderlings of Hogna carolinensis"

Contact with maternal parent and siblings affects hunting behavior, learning, and central nervous system development in spiderlings of Hogna carolinensis (Araeneae: Lycosidae) - PubMed

The purpose of this study was to determine the effects of early experience (rearing conditions) on the central nervous system (CNS) and behavior of spiderlings of Hogna carolinensis (Lycosidae). We were interested in whether or not spiderlings that were allowed to remain in contact with their...

pubmed.ncbi.nlm.nih.gov

Please don't get super mad because I referenced another Arachnid, as I'm well aware I'm making a leap when comparing two different animals. I used this study to make an assumption and formulate a question in my head. Honestly asking a question like this would have been well-recieved back in my University days so I'm a bit confused and wary now.

If you think I'm woefully off base by comparing the two and making this assumption, then simply state that.

@everybody
I have to ask:
- Are Tarantulas so different that things that affect other related members of their family do not apply to them?
- Am I completely stupid for thinking that Tarantula slings would benefit in development and behavior from spending more time with their mothers?
- Why do Baboon species raise their young around their burrows if it was pointless?

I just got questions, man. They're all unanswered in my head.

Thank god you can search! Keep it up!

Most behavioral questions and even basic physiological questions have no known answers because there’s little grant $.

The only main areas for $

1. Taxonomy
2. Venom research
3. Ecology, ie how to protect our little friends

 

[sparticus]

"is it possible that extra time with mom can positively affect the development and behavior of slings in captivity? Are we (the hobby) depriving our newborn slings an aspect of their early development?"

I think it's a very difficult question to answer with any degree of certainty, and will be variable depending on species involved. Like I said, the maternal care for herpyllus ecclesiasticus clearly ended at the point that the slings left the egg case. She was done with those things, and pretty frantic about getting away from them. There definitely were some that hatched out looking beefier than others, which leads me to believe some had fed inside the egg sac, either on deceased or possibly (formerly) live siblings. No experience with tarantula maternal care, so no comment there, except that you'd only be depriving the surviving slings, I'm sure the ones that would have been eaten by their siblings aren't feeling quite so deprived. Seems a lot of the behaviors (webbing, hunting, etc) are pretty heavily instinctual, but nuances of behavior are hard to assess in species so different from our own.

 

[Mustafa67]

Thanks. I do understand what they're doing, I'm moreso interested in the how and the why.

It's an idea that grew into more questions, so I don't really have a singular question to be answered. I'm searching for information and insight.

I guess to put it short: another question I have is, "is it possible that extra time with mom can positively affect the development and behavior of slings in captivity? Are we (the hobby) depriving our newborn slings an aspect of their early development?"

Questions questions questions.

Thank you for your time and attention.

As a trainee therapist I find your questions interesting but like @viper69 says there isn’t funding for research which would be ESSENTIAL to fully answer your questions.

I would guess like @LucN says, I don’t know about the brain of a spider of the academic literature on arachnid brains or tarantulas or even more specific, which genus and species (maybe a quick Google Scholar look could I don‘t know) but the brain probably IS gonna be less developed than animals which have maternal bonds (mammals or top tier mammals). I guess mum would eat them or they would eat each other because they’re not like mammals. But research would have to be done to 100% know the answer.

I think it’s very easy to humanise tarantulas… meaning to think of lower-level brain animals as we would think for us but this is the wrong approach. They’re not mammals and not taught the care instinct or not given “motherly love” like us humans, monkeys, dogs or other higher level mammals are. Their primary function in life is to SURVIVE

If you look into Davis and Panksepp (2018) book on personality looking through an evolutionary lens it’s really facinating. Not about only tarantulas but about the development of emotions and personality through an evolutionary approach. But yeah, take it with a grain of salt and remember the limitations as you read it. Still it’s a facinating read. The book is called: “The Emotional Foundations of Personality A Neurobiological and Evolutionary Approach”

 

[l4nsky]

Thanks for your reply... so this brings up a question for me regarding captive reproduction as I'm aware you are heavily focused on the breeding aspect.

You don't need to answer it if it's an issue... really just ignore me if it annoys you as I am not trying to anger or upset anybody by simply asking questions.

When you say "it doesn't really have an effect in captive reproduction" can you elaborate what you mean? As in they slings do not need to stay around each other or with mom in order to develop fully? I understand that you can produce a sac with all surviving slings, but based on what I've read, my understanding is that we don't have a full conclusion as to the adaptive significance of this behaviour... And if I may ASSUME something, this suggests that socialization/learned behaviour may be more important to development and survival than we've yet to realize.

No issue, the meaning behind my statement is very few people even allow a female to carry an eggsack full term and hatch it out in captivity and even in those instances, natural dispersion isn't really allowed to happen.

The standard operating procedure is pull the eggsack from the female after x days, artificially incubate until 2i, and then separate before cannibalism potentially starts. The captive observation of dispersion will never happen in this scenario.

 

[AphonopelmaTX]

I will apologize for pinging you unnecessarily Aphonopelma, I won't do it again. I just thought I would ping people whom I've observed displaying deep wells of knowledge about Arachnid science and the hobby on this forum to expand my own knowledge of the subject.

Feel free to tag me in any post at any time. I'm always willing to share what I know or refer you to an article that would answer your questions. It's just in this instance you asked a series of questions that were already answered in the very same article you posted so I wasn't sure if you read the whole article, missed it somehow, or what.

- Are Tarantulas so different that things that affect other related members of their family do not apply to them?

Tarantulas are not so different from each other that a behavioral study of one taxon within the family Theraphosidae wouldn't necessarily mean it wouldn't apply to another. From my own literature research, it would seem all tarantulas have a set of "pre-programmed" behaviors originating from the more basal mygalomorphae taxa. What makes tarantulas unique within the infraorder is their diversity and adaptations to specific habitats. For example, the species Pachistopelma bromelicola has adapted both physically and behaviorally to life within bromeliad plants which makes them unique among the tarantulas. However, mate selection, breeding behavior, egg production, etc. is the same among them and all other tarantulas. The issue in proving how much all tarantulas have in common behaviorally is their cryptic lifestyle which makes them nearly impossible to find and study. A group of interested individuals from around the world would really have to be in the right place at the right time, and think to record their observations, to determine if all tarantula spiderlings disperse in a single file line such as shown for Tliltocatl vagans, as an example. It is what makes studies such as the one posted here so remarkable.

- Am I completely stupid for thinking that Tarantula slings would benefit in development and behavior from spending more time with their mothers?

The idea that tarantula spiderlings would benefit in development and behavior from spending more time with their mothers is absolutely not a stupid thought. The few published field observations, and what little anecdotal evidence there is on the internet and in hobby journals from captive breeding, show that tarantula mothers have a maternal instinct. If you were to pull an egg sack away from a mom tarantula, you might see the heart breaking behavior of it trying to fight you off and the resulting pacing which indicates a level of stress that occurs when her babies disappear. We know for sure that in the wild tarantula mothers have a set of behaviors that aid in the development of their offspring. For example, tarantula moms will "sun" their egg sacks by pushing them to the top of their burrows so they get enough heat. We also know that tarantula moms roll their egg sacks around inside their burrow to keep the eggs from sticking to each other. We also know from published observations such as the one linked to here that spiderlings upon emerging from the egg sack stick around mom's burrow for protection and food until they are ready to head out on their own. So we see that tarantulas around the world regardless of taxon have the same set of maternal behaviors that benefit in their development from egg to fully formed spiderling, but captive breeding efforts over the decades show without a doubt that spiderlings are born with the instincts to survive without mom around.

- Why do Baboon species raise their young around their burrows if it was pointless?

I'm not sure what species of tarantula you are thinking of for this question or how you came to conclusion spiderlings of this group hang around their mothers' burrow. As far as I know there have been no published observations of an African species of tarantula that showed maternal instincts. The published observations of maternal behaviors are of species found in the Americas.

In summary, there is enough published in the academic literature to show us that the tarantulas are not too different from each other by any criteria, or even that their biology is too different from other chelicerates. The captive breeding and keeping of tarantulas for the pet trade has also shown us this as well, but captivity tells us absolutely nothing about their ecology or in other words how different species interact with their environment. Comparative ecological studies of different tarantula species around the world is one area where the academic literature is severely lacking. We need more people with boots on the ground studying these things for long periods of time to fill in some of the gaps in tarantula natural history.

 

[SpookySpooder]

Thanks for the replies. It's been quite helpful in refining my thoughts and ideas.

The short answer would be no. Spending extra time with mom would simply increase the chances of further cannibalism. No spider gets "gentler" because of the upbringing, so to speak. Whether they're born in the wild or in captivity, they remain wild and totally unpredictable. Some individuals will simply be more tolerant to our interactions than others. A "docile" spider can become defensive over time. There's even been cases that individuals change temperament radically from molt to molt. It's the luck of the draw in the end. Of course keeping interactions to a minimum will decrease an individual to suddenly feel threatened. I try my best to open my cages as gently as possible to avoid startling them too much. So far, they're very laid back and easy to work with.

I understand your point on temperament, but please note: I am not saying that this "socialization" or "development" is meant to "tame" or "condition" a Tarantula into becoming a docile pet. I only meant it in the sense that perhaps they could learn or gain something from the extra time spent with mom. What that is, I do not have a clue. Though as Sparticus alluded to: it would probably serve some sort of survival function. Perhaps they stay with mom just for extra food, perhaps for early protection. Maybe the proximity and stimulation from touch helps develop a denser ganglia cluster, as evidenced in wolf spiders.

Thank god you can search! Keep it up!

Most behavioral questions and even basic physiological questions have no known answers because there’s little grant $.

The only main areas for $

1. Taxonomy
2. Venom research
3. Ecology, ie how to protect our little friends

Stop making me search for everything and give me your treasure troves of bookmarked studies and papers!

How can a God be both omniscient and yet provide no answers?! And don't give me that "works in mysterious ways... trials and tribulations" copout!

This lack of research funding is truly a tough pill to swallow. Namely because being left without a conclusive answer is quite unfulfilling, but I guess that's what the entire hobby has been coping with for decades...

I think it's a very difficult question to answer with any degree of certainty, and will be variable depending on species involved. Like I said, the maternal care for herpyllus ecclesiasticus clearly ended at the point that the slings left the egg case. She was done with those things, and pretty frantic about getting away from them. There definitely were some that hatched out looking beefier than others, which leads me to believe some had fed inside the egg sac, either on deceased or possibly (formerly) live siblings. No experience with tarantula maternal care, so no comment there, except that you'd only be depriving the surviving slings, I'm sure the ones that would have been eaten by their siblings aren't feeling quite so deprived. Seems a lot of the behaviors (webbing, hunting, etc) are pretty heavily instinctual, but nuances of behavior are hard to assess in species so different from our own.

As above. I couldn't help but laugh at some of your comments though, thanks.

Seemingly frantic to get away from their kids? Sounds like some human parents!

I'm practically convinced T's are not as "low order" or "base instincts" as I was a few days ago. Their behaviors seem to be quite complex when compared to other organisms I'm versed about... corals, snails, shrimp, and ants, worms for example. Maybe not as complex as a reptile, a bird, octopus, or a mammal, but certainly pretty complex for something "without a brain."

Perhaps they are just displaying their instinctual maternal adaptations for survival, and I am reading too deep into it.

As a trainee therapist I find your questions interesting but like @viper69 says there isn’t funding for research which would be ESSENTIAL to fully answer your questions.

I would guess like @LucN says, I don’t know about the brain of a spider of the academic literature on arachnid brains or tarantulas or even more specific, which genus and species (maybe a quick Google Scholar look could I don‘t know) but the brain probably IS gonna be less developed than animals which have maternal bonds (mammals or top tier mammals). I guess mum would eat them or they would eat each other because they’re not like mammals. But research would have to be done to 100% know the answer.

I think it’s very easy to humanise tarantulas… meaning to think of lower-level brain animals as we would think for us but this is the wrong approach. They’re not mammals and not taught the care instinct or not given “motherly love” like us humans, monkeys, dogs or other higher level mammals are. Their primary function in life is to SURVIVE

If you look into Davis and Panksepp (2018) book on personality looking through an evolutionary lens it’s really facinating. Not about only tarantulas but about the development of emotions and personality through an evolutionary approach. But yeah, take it with a grain of salt and remember the limitations as you read it. Still it’s a facinating read. The book is called: “The Emotional Foundations of Personality A Neurobiological and Evolutionary Approach”

Boooo!

Even without conclusive research, can we not play with ideas and come up with theories based on what we do know and have observed? I'm not calling for a decisive conclusion on the subject by any means!
Though I will understand if anybody chooses to hold off on forming a conclusion one way or the other until there is more data.

Make no mistake, I am not under any sort of anthropomorphic delusion, thinking that Tarantulas have the same capacity for emotional bonds and mental development as say a dolphin or a raven or a dog or an elephant or a primate. I'm merely wondering if they are indeed as basic as the hobby has stamped them to be, and from what I've seen so far, there is no conclusive evidence either way due to a lack of research.

In the marine field, fish were assumed to NOT have feelings or personality for a long time, until adequate studies were done to prove certain species do.

Aren't we assuming Tarantulas all programmed identically and follow a set of basic rules as well, (like ants or bees?) We have plenty of anecdotal references that they differ from one another in temperament and behavior, even within the same species and often the same individual.

Tangent thought: if "personality" (behavior?) differs within an individual between molts, then shouldn't that be a clue that they aren't all programmed a certain way? Unless that instinctual programming encompasses all the types of behaviors displayed/observed and all Tarantulas eventually display the same set of behaviors at one point...

I know I am assuming a lot in thinking they might be more complex than we give them credit for, but if anybody has evidence that they are DEFINITELY base instinct animals and they're all exactly the same then I would like to see it. Not because I don't believe you, but because I simply haven't seen it yet. (Ignorant)

I can think of another example of Arachnid complex behavior: we have studies that show jumpers and wolf spiders communicate to one another through vibrations they generate by drumming. Researchers recorded these different drumming patterns and theorize there are various drumming signals that could mean many different things--what they are, we don't know yet.
Mating is not the only instance of reported Arachnid communications, though I concede it would be a stretch to assume Tarantulas also communicate through this drumming method because no one has done a study on it (to my knowledge). However when I think of mature males drumming to females, and all the posts about "different species of T's drumming to each other and sitting on the enclosure walls near each other" I can't help but wonder if they are indeed attempting communication in some form.

Again, I'm aware this is a comparison between different animals. But I'm assuming Arachnids aren't THAT different. I know I'm assuming a lot of things when forming these thoughts.

I appreciate the recommendation, I will add it to my backlog and try to source an online copy. If I can't, I'll have to find it somewhere else. Mind if I borrow your copy? ... I've returned every book I've ever borrowed, just check my library card.

No issue, the meaning behind my statement is very few people even allow a female to carry an eggsack full term and hatch it out in captivity and even in those instances, natural dispersion isn't really allowed to happen.

The standard operating procedure is pull the eggsack from the female after x days, artificially incubate until 2i, and then separate before cannibalism potentially starts. The captive observation of dispersion will never happen in this scenario.

Appreciate the clarification. Any insight you want to add to my messy and incomplete web of thoughts?

This is going much further than the study I've posted. Maybe I should quit, but I can't stop having ideas and questions.

Another question if you don't mind... feel free to refuse to answer and opt out. I simply don't want to impose on anybody.

I understand you primarily have a focus on breeding, so this one is directly regarding the breeding process.

It's been stated--backed up even, by decades of breeding and thousands of successful eggsacs--that most slings will develop and grow up perfectly healthy when removed from their mom and incubated artificially.

I've also heard it stated (non-academically) that because natural cannibalism isn't allowed in breeder-reared sacs, that the developmentally challenged or genetically inferior slings that would normally be cannibalized are raised out and passed on. If this is true, would you consider that leaving them to develop with mom might potentially be a natural way to cull out these less fit (weaker, smaller, slower developing) specimens and allow the stronger ones a better chance at survival? Or would the selection simply be random amongst all the slings?

I can reference a paper on Guppy Genetics by Diana Walstad on the effects of this type of breeding in fancy guppies. Perhaps it would apply here as well?
The short of it is: because most guppy breeders don't grow out every specimen to their full life to select against those with health issues later in life and breed almost every specimen regardless of health, they concentrate and pass on faulty genetics. Essentially lazy and irresponsible profit motivated breeding of guppies has weakened the genetics of entire breeding groups and lines.

It may not apply here. Please forgive me for making the connection if it doesn't.

2nd part: knowing what we know about the development of other Arachnids raised by their moms, do you perhaps have at least a tiny suspicion that this might also apply to at least one Tarantula species or genus? If so, which one?

Bonus question: you mentioned standard procedure for breeders, but are you aware of any researchers or hobbyists who have attempted to rear their eggsacs with mom and without mom to make comparisons? I know there is a lot of cannibalism, and at a certain point even mom starts predating on her young, so most people do not attempt it.

I recall an experiment (Purdue Uni I think) in which they raised a colony of Monocentra balfouri side by side with solo specimens and recorded stuff such as rate of growth and level of activity amongst other variables. Just wondering if anybody has done that for other species/slings.

Please note: I am not attempting to criticize or question how you or the hobby has refined the breeding process.

Feel free to tag me in any post at any time. I'm always willing to share what I know or refer you to an article that would answer your questions. It's just in this instance you asked a series of questions that were already answered in the very same article you posted so I wasn't sure if you read the whole article, missed it somehow, or what.

Tarantulas are not so different from each other that a behavioral study of one taxon within the family Theraphosidae wouldn't necessarily mean it wouldn't apply to another. From my own literature research, it would seem all tarantulas have a set of "pre-programmed" behaviors originating from the more basal mygalomorphae taxa. What makes tarantulas unique within the infraorder is their diversity and adaptations to specific habitats. For example, the species Pachistopelma bromelicola has adapted both physically and behaviorally to life within bromeliad plants which makes them unique among the tarantulas. However, mate selection, breeding behavior, egg production, etc. is the same among them and all other tarantulas. The issue in proving how much all tarantulas have in common behaviorally is their cryptic lifestyle which makes them nearly impossible to find and study. A group of interested individuals from around the world would really have to be in the right place at the right time, and think to record their observations, to determine if all tarantula spiderlings disperse in a single file line such as shown for Tliltocatl vagans, as an example. It is what makes studies such as the one posted here so remarkable.



The idea that tarantula spiderlings would benefit in development and behavior from spending more time with their mothers is absolutely not a stupid thought. The few published field observations, and what little anecdotal evidence there is on the internet and in hobby journals from captive breeding, show that tarantula mothers have a maternal instinct. If you were to pull an egg sack away from a mom tarantula, you might see the heart breaking behavior of it trying to fight you off and the resulting pacing which indicates a level of stress that occurs when her babies disappear. We know for sure that in the wild tarantula mothers have a set of behaviors that aid in the development of their offspring. For example, tarantula moms will "sun" their egg sacks by pushing them to the top of their burrows so they get enough heat. We also know that tarantula moms roll their egg sacks around inside their burrow to keep the eggs from sticking to each other. We also know from published observations such as the one linked to here that spiderlings upon emerging from the egg sack stick around mom's burrow for protection and food until they are ready to head out on their own. So we see that tarantulas around the world regardless of taxon have the same set of maternal behaviors that benefit in their development from egg to fully formed spiderling, but captive breeding efforts over the decades show without a doubt that spiderlings are born with the instincts to survive without mom around.



I'm not sure what species of tarantula you are thinking of for this question or how you came to conclusion spiderlings of this group hang around their mothers' burrow. As far as I know there have been no published observations of an African species of tarantula that showed maternal instincts. The published observations of maternal behaviors are of species found in the Americas.

In summary, there is enough published in the academic literature to show us that the tarantulas are not too different from each other by any criteria, or even that their biology is too different from other chelicerates. The captive breeding and keeping of tarantulas for the pet trade has also shown us this as well, but captivity tells us absolutely nothing about their ecology or in other words how different species interact with their environment. Comparative ecological studies of different tarantula species around the world is one area where the academic literature is severely lacking. We need more people with boots on the ground studying these things for long periods of time to fill in some of the gaps in tarantula natural history.

Oh boy... such a wonderfully informative and thoughtfully written response. I'm very glad that I tagged you, despite my fumbling about.

First of all, I appreciate your patience and time. I can only attribute my oversight to poor focus and jumping between multiple publications and formulating thoughts and questions without giving time for the information to fully sink in or to seek more information. I'm a bit scatterbrained and my ADHD doesn't help me much. I needed to post process but didn't because I got excited to think that T's had the potential to "socialize" (not social interactions, but develop) and potentially learn behaviors from their moms. Perhaps if I held off on posting overnight I would have formulted better thoughts and edited a better worded post.

Second, I will apologize in advance for not having a reply adequate to thank you for taking the time to explain what you have to me.

You've both answered a lot of questions and left a bunch stamped: "To Be Answered At a Later Date" in my mind.

A lot of the questions and ponderings I've had above could be put on pause by what you and other members have explained. Observations on their base instincts and my assumptions could be simplified to "a set of base behaviors and instincts" and written off due to a lack of research or observations.

A lot of my ponderings have been reinforced by what you've mentioned as well, namely with the mention of maternal instincts observed in the wild. It would stand to reason that perhaps certain species within the taxa would develop a special survival adaptation for the environment they live in, and perhaps in an area with a lower concentration of smaller prey animals (as Sparticus mentioned) the young simply stay at home longer because of the lack of food their size. Kind of like how 30 year olds in my demographic still live with their parents!

In regards to my Baboon comment:
I cannot find what I read (it was a PDF image with writing but I'm unsure if it a peer reviewed study) but it was of an observation of Monocentropus balfouri in the wild. Babies of various ages and sizes were found living around and IN the burrow with mom. Also found a write up about the development rate and behaviors in captivity in solo specimens vs. those kept in groups that suggests living together is beneficial for this species as it helps them develop faster earlier, perhaps resulting in a more successful dispersal later when mom kicks them all out of her space. I probably should have looked at the sources before running with the ideas.

Another Baboon species that was in my mind was Harpactira pulchripes. (This one I can remember the source for, but it isn't an academic study or paper.) This excerpt is from Tom Patterson's website on his page regarding Harpactira pulchripes: "In the wild, females have been spotted with older slings still congregating around them. Like the Monocentropus balfouri, it appears that this baboon mother is quite nurturing to her young,"

Perhaps it is just unverified commentary? I have not had the chance to speak to Tom Patterson or find a paper on the subject.

I jumped a few steps and connected some dots on this literally last night, perhaps incorrectly. Yes, I had to take a few steps back, thanks for the wealth of insight and information. Really, thanks for your input everybody, I was half expecting to just get all my ideas shot down.