Are my Ts emitting molting pheromones?

killy

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I'm half-kidding, but half-serious on this one - I mean, it seems that, given the vulnerability of the spider, molting is something it would want to keep secret, but I just had my 4th molt in as many days, and it looks like I can expect more ... it makes me wonder if something is in the air ... all 4 of them are in close proximity, and although all of them have been exhibiting the tell-tale signs of pre-molt the past couple of weeks, (so the molts in themselves are not surprising), I still find it odd that they're going off in rapid succession like a string of Chinese firecrackers ... could something be triggering the cocked guns, or is all of this a co-incidence? What about our unseasonably warm weather the last couple of days, could that be it?

In a previous post detailing the last 3 molts, I asked the rhetorical question, "Who's next?" and today I found out - Tuppence, my 1/4 inch G. rosea, stripped down this evening - he's so cute - he's now a quarter-and-a-half inch (he just looks too darned tiny to claim he's 3/8" with a straight face) - so that's my Chaco on Thursday, my vagans on Friday, my LP yesterday, and Tuppence today ...

This series of multiple wardrobe changes has never happened to my brood before - I know that my versi has been acting pre-moltish, as has my GBB and my Avic avic, (in fact, of my 10 Ts, only 2 are interested in food these days), so let me tempt fate again and ask, "Who's next?"

(Maybe I should call in sick tomorrow ... shhhhhhhh!)
 

Lsal

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I've wondered this too, it seems like a lot of people have stories of multiple molts at the same time. Out of the four t's that I have, two have molted in the past week and a half, and I have one that just sealed off its burrow and went into premolt. I am actually beginning to think the fourth one is in premolt as well. Even one of my scorpions molted last week. It just seems like more than a coincidence sometimes. Perhaps it has something to do with weather conditions; the past couple of weeks the days have gotten shorter where I live and the humidity has most likely changed also. I keep them under consistent temp/humidity conditions but maybe they sense something else. I think it would be an interesting topic of research.

Anyways, congratulations on the molts, I work night shifts so I have been lucky enough to be home and awake to witness a couple of mine ;)
 

Ictinike

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I've always considered BP or Barometric pressure helps them and find many of mine seem to molt, if they are near and waiting, until the pressure in the atmosphere drops.

Think of it as a way to help them relieve themselves of their old exoskeleton easier since they have to exude less internal pressure to pump it off.
 

GregorSamsa

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Re: barometric pressure changes...
I had 2 molts right before our 1st snow. Didn't think of this. Interesting.
 

leoferus

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My two recent molts occurred immediately before a big storm. All of my other premolts (3) are on standby. I like the BP idea. Too bad I don't have a BP gauge. I'll see what I can do. Where's can I get a U shaped tube at 10pm?
 

MS6582

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Two of my T's have gone into hiding and fully sealed up their hides just days apart, I thought this was odd for sure but I'm new so just thought there was a reason for it. First I thought it could be the cold but after searching here it seems it could be premolt too, maybe I'll have two molts days apart.
 
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Mr. Irminia

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this is interesting, i keep a log of all my T's and their molts, funny enough both of my P. ornata's just molted and they are both about two weeks ahead of their projected molts. This is approximate of course but if anything at their size now they should have gone past this time frame not this far ahead.As for pheromones i have no clue the rest of my T's so far have stuck to their projected schedule.
 

DrAce

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This has been discussed before, with some considerable data. I believe it was TalkenLate who gave some of the most detailed information on the subject.

I'm not personally convinced that barometric pressure is responsible. After all, barometric pressure shouldn't affect the inner works of a spider if they're filled with liquid (which is nearly incompresable).

It may, however, help them when they're flushing fluid from limbs to compress what's left.

Either way, this has been documented, and it seems that significant changes in barometric pressure can certainly aid in moulting. Maybe from humidity, maybe from pressure.

It's unlikely to be pheromones.
 

leoferus

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Thinking of it in terms of hydrostatic pressure... although liquids cannot be compressed they can exert forces. This, of course, is influenced by the pressure countering a liquid's hydrostatic pressure. It is interesting then... a drop in barometric pressure might make it easier to "pump".

I'm just hoping to create more discussion. My understanding of hydrostatic pressure can be wrong being that it's been over ten years since I last had to work with those concepts. Carry on.

P.S. I was supporting what was stated above my post.
 
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Stopdroproll

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Earlier this year, I've had all my Ts (6) molt within 2 weeks. Sucked because I just bought a bunch of crickets and no one ate. My GBB and brocklehursti just molted and I'm expecting my darlingi and pulchripes to molt soon.
 

losct2381

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Wow this thread makes me think. Last fri dec 10 I woke up and my G.rosea was molting. I went to work when I got home at about seven pm my 2 inch t- blondi was on it's back molting. And their tanks are On top of each other
 

Anastasia

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It's unlikely to be pheromones.
I absolutely agree with this, molting is a body changing process and timely and very much strength consuming.
I dont think it can be synchronized by sprinkling fairy dust (in this case molting pheromones)
I'll though, I did have a theory that adult female tarantulas can speed up and molt in a hurry to mate when mature male tapping around
But, that is just my thinking
 

AphonopelmaTX

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An arthropod can't begin ecdysis (molting) without first having the new endo and meso cuticles developed underneath the old exocuticle and this takes time to complete. Once complete and the arthropod is ready, a hormone from the ganglion (I can't remember if it's the supra or subesophogeal) kicks off the rest of the physiological changes to begin the molt process. Given the complexity and the time required for ecdysis, my best guess is that it all works on a seasonal schedule of the arthropod's natural habitat or outside of that schedule by a raised metabolic rate from artificial environments (constant warm temperatures, constant prey availability, etc) or even a combination of both. In all the examples in this post of the tarantula species that molt in the same timespan, the one thing they have in common are that they are from the southern hemisphere. The onset of the winter season in the northern hemisphere is the onset of the spring season in the southern hemisphere thus may support a hypothesis of a natural molting schedule. It would be interesting to know if those who have species from both northern and southern hemispheres or a combination of eastern, western, northern, and southern hemispheres all molt at the same time in accordance to their natural habitat.
 

Najakeeper

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Think about it this way: A signal pheremone may not necessarily come right at the molting time, causing others to molt, which is not possible as explained above. But lets say one of the spiders is starting a seasonal molt and produces the pheromone then, which causes others close by to sense it and kickstart their cycle, which would cause them to molt very close to each other when their body is ready for it.
 

Bill S

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Barometric pressure changes far more frequently than tarantulas molt. If a tarantula is approaching a molt the barometric pressure might speed it up or slow it down a tiny bit - but that's about all it can do. Seasons, daylight rhythms, temperatures (long term), feeding frequency and quantity, and a few other factors all go into the mix of influences. But in any given collection temperatures are likely to be the same, as are feeding patterns, light/dark patterns, season, etc. I suspect that has more influence on synchronizing molting than just barometric pressure change.
 

killy

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... lets say one of the spiders is starting a seasonal molt and produces the pheromone then, which causes others close by to sense it and kickstart their cycle, which would cause them to molt very close to each other when their body is ready for it.
This is sort of what I was hypothesizing too, and you described it so well right there that I'm starting to wonder again ...

And now, co-incidental with the return of cool weather to So Cal, the molting streak has ended - my avic did not molt, nor did my little A genic, and in fact, my GBB, who has been acting pre-moltish for weeks, actually accepted food this morning - GO FIGURE!!!

As I said originally, I was half-facetious, but also half-very-curious about the pheromone possibility, which is why I didn't post this thread in the "questions" section, but it sure did seem peculiar, all the neighbors trying to keep up with the Joneses all of a sudden. It's not likely that humidity had anything to do with it, as our "summer in December" weather was in fact very dry (unless, and here I go hypothesizing again, the sudden warmth triggered a "forced spring" - kind of like refrigerating flower bulbs to trick them into blooming, which would then explain the just-as-sudden end to the cascade of molts) ... the barometric pressure angle is interesting, and I think I'll do a little research of my own and get back to all of you ... thanks for the input!

Meanwhile, I composed a family portrait of "the Moltin' Four," ... I wanted to do this with the live versions, but thought better of it ... here they are (left - G. pulchripes; top center - L. Parahybana ; right - B. vagans; and the teensy one lower center - G. rosea.


 
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presurcukr

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The most likely reason for the T's molting so close is your feeding schedule.Think about it you probably feed them same so they should molt close to the same time.I find that most of my T's that are close to the same size go off within a few day's or a week of each other .Even if they are different species.

---------- Post added at 10:19 PM ---------- Previous post was at 10:14 PM ----------

It would be interesting to know if those who have species from both northern and southern hemispheres or a combination of eastern, western, northern, and southern hemispheres all molt at the same time in accordance to their natural habitat.
I have about 206 Ts, and it is more a size thing not a seasonal thing as they all have a climate controlled environment.
 

killy

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Same size? You mean like the Chaco and the Rosie? :) Just kidding, I know what you mean - but my other Ts that are on the same feeding schedule and about the same size didn't molt (not even the ones acting like they want to), so I'm still thinking it had something to do with the wierd blip in the weather screen. Maybe we'll never know, and I guess in the final analysis it doesn't matter ... still, the mystery of molting enchants me like a siren song ...
 

MS6582

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The most likely reason for the T's molting so close is your feeding schedule.Think about it you probably feed them same so they should molt close to the same time.I find that most of my T's that are close to the same size go off within a few day's or a week of each other .Even if they are different species.

I just thought about this today when I was feeding my T's and watching them eat... the light came on! Since it seems feeding is most directly linked to molting it would make sense that since we control their feeding we control their molts.
 
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