Tarantula / Human recognition

[Dana C]

First let me acknowledge that I know that spiders and tarantulas are basically instinct driven. I have no idea how large their brains are in relation to their bodies either. Having said that, I had observed some interesting things with some of mine.

I had some guests over and showed them my limited collection of about 8, all new world, all females and all but two are adults. In showing my T's to my guests, I took three or four out of their enclosures so my guests could see them without glass or plastic between them and the tarantulas. I don't handle my "kids" in order to "show off". I handle most of them once a week. When I handle them, I usually coax them up the side of their enclosure on to my hand and did the same this time.
My T's have never displayed any defensive or agressive postures with me ever. when I offered to let one of my guests hold the G rosea, she said she would but the spider wanted nothing to do with her. With me she is amiable, and docile. When I took the G Pulchripes girl, now almost 6", everyone was fascinated because of her size. I let her walk up my arm and she proceeded down my back on to the bed and then returned to my back. One of my guests who has had some experience with exotic pets offered to coax her on to his hand so we could place her back into her enclosure. She would have nothing to do with him. She was nudged onto bed again and I gently coaxed her on to my hand easily.
We did this with an A. new river as well. My T's would let me handle them with no objection but didn't really want anyone else to touch them.

Here is the question: To my knowledge Tarantulas are not able to smell nor hear. They can see but not real well and only sense vibrations in their surroundings. Yet my T's are fine with me but not with anyone else. I have no problem removing them from their cages handling them or even stroking them. They are not always as wild about sometimes but it is usually ok.
Is their some other mechanism for recognition that I don't know about? Without trying to anthropamorhize my "kids", I got the sense of limited recognition.

Am I full of it, or is it possible?

 

[DaveM]

There was a recent poll on this topic. The majority of AB members thought Ts don't distinguish between individual humans. I think they could become habituated to the ways a certain keeper may move when handling them, though.

 

[bravesvikings20]

This topic comes up at least once a week I swear...

 

[madamoisele]

My personal theory is that the T's learn the presence and scent/taste (?) (through chemoreceptors in their feet) of their owners. While they are accustomed to you, your sounds/vibrations/taste/scent - it's possible they marked the difference between you, a known safe haven, and other, unknown people.

I have no evidence for any of this. Just personal speculation.

 

[AphonopelmaTX]

Although tarantulas, and all spiders for that matter, can't hear, taste, and smell in the same way we (people) do they can to a degree with the mechano and chemo receptive bristles on their legs. The chemoreceptors being located on the tarsus and the mechanoreceptors covering a good portion of the body. For recognition of an individual person, tarantulas would have to have some capacity for memory. They can taste you and they can hear you (in the primitive spider way of course) but the question is, can they remember that taste and can they remember the unique sound signature you make (for lack of a better way to say it). If tarantulas have some degree of memory then "owner recognition" would be plausible.

 

[DaveM]

Yes, and surely it's a matter of degree. Even bacteria exhibit an environmental response priming which could be thought of as an extremely simple kind of memory. By analogy, few of us casual stargazing humans can remember the positions of all the visible stars in the sky, but if some advanced aliens experimented on us by progressively distorting the starscape, at some point we would begin to get the feeling that the stars looked wrong. And as more stars were moved, our feeling would gradually become a certainty.
I think a T might more easily get the feeling that something is wrong when handled by an unfamiliar person, becoming alarmed without any realization that the new handler is an entirely different being. When "learning" is too strong a word, animal psychologists use the term "habituation". I think Ts become habituated to a familiar handler, without being even remotely close to so complex an experience as recognition of identity.

 

[synyster]

My opinion is that your guests just became a bit more nervous when approaching the spider making their breathing become harder. And when exhaling next to a spider, we all know this changes the spiders reaction. So combining the fact that the guests were exhaling harder than usual next to the spider and you were calm and breathing normally, it felt less threatened to stay where it already was.

Again, this is my opinion about your experience.

 

[jakykong]

My opinion is that your guests just became a bit more nervous when approaching the spider making their breathing become harder. And when exhaling next to a spider, we all know this changes the spiders reaction. So combining the fact that the guests were exhaling harder than usual next to the spider and you were calm and breathing normally, it felt less threatened to stay where it already was.

Again, this is my opinion about your experience.

That's actually a fairly fascinating hypothesis; it would seem very amenable to testing.

I recently ended up with a G. rosea, and in its enclosure, if I turn on my A/C unit blowing in that general direction, it wanders endlessly around the cage. Point it away, the wandering stops and it goes back to its spot on top of its hide (of course! Why go into it when you can sit atop it?). The air from that distance isn't within my ability to perceive (not a strong fan), so clearly they're highly sensitive to wafts of air. Interesting to watch.

Is it OK for the Ts to be handled that much, though? I would think it would be stressful for them...

 

[captmarga]

Ask a question like this and you will get as many answers are there are people doing the answering. Everyone has their own opinion, and even any kind of study that people have done do not yet yield solid answers.

I am convinced my Ts know which day is feeding day. I don't handle on feeding day, unless they come out of their habitat on their own and sit on my hand. I have several that do that. I have 115 Ts, over 55 different species, and I have specimens that do not act "stereotypical".

One of my P irminias sits out in the open and lets me take photos of it. Same with one of my OBTs. My daughter's behlei and my moderatum love to come out and sit on a hand. They then do NOT want to go back into their enclosures and have to be lifted or prodded back at times.

I talk to them all the time. They have music played. There is a train behind the office. They don't freak at noises, or people talking, or coming in. Many of them rush over and sit at the closest edge to me while I drop in their crickets. Morado, the T cupreus that lost all the legs, sat out in the open whilst ill, then when whole again, went back to being a spider in a web-tube jungle.

Somewhere in their little primitive nodes, they recognize smell or patterns or more. Some individuals perhaps more than others, just as with any other animal.

I love all of my Ts, even the ones that don't like me much! But those who show some kind of behaviour that one can see as "interaction" are all the better for me.

Marga

 

[High_Rolling_T]

My opinion is that your guests just became a bit more nervous when approaching the spider making their breathing become harder. And when exhaling next to a spider, we all know this changes the spiders reaction. So combining the fact that the guests were exhaling harder than usual next to the spider and you were calm and breathing normally, it felt less threatened to stay where it already was.

Again, this is my opinion about your experience.

Don't forget a heightened heart rate and most likely(even if not noticeable) a increase of perspiration. You'd get nervous too climbing onto a throbbing, salty hand while being blown on.

As an example of how sensitive tarantulas are to air pressure, here is a microscope video of the effects of moving a hand 1 meter(3.2 feet) from the leg of a Pterinochilus murinus [video=youtube;pYyTYj9PqUY]http://www.youtube.com/watch?v=pYyTYj9PqUY[/video]

 

[Shrike]

Cool video. Thanks for sharing!