Question about Mature Male Sizes

Gods Spartan

Arachnopeon
Joined
Jul 15, 2014
Messages
47
So, my male G. pulchripies is currently in the middle of molting. I would put him at around d 4.5 inches before this molt. In doing a little research, it appears that males of the same species mature at different sizes. I've seen MMs at 5.5 and MMs at 7.5.

Really hoping he doesn't mature out on this molt. Regardless, the question I have has to do with varying sizes of MMs.

Is there any control that we as keepers can have on the outcome of MMs ultimate molting?

Does it have to do with breeding or more to do with feeding, and environmental controls?

BTW, my male is probably 3 years old and I haven't power fed him by any stretch of the imagination. 3-4(max) Crickets a week. IMG_20170225_144117545_HDR.jpg
 

Ungoliant

Malleus Aranearum
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Is there any control that we as keepers can have on the outcome of MMs ultimate molting?

Does it have to do with breeding or more to do with feeding, and environmental controls?
I have no idea what factors contribute to a tarantula's maximum size, but I believe the rate of maturation is affected by temperature and feeding schedule. Warmer temperatures and more frequent feeding accelerate growth (though not necessarily maximum size).
 

Nightstalker47

Arachnoking
Joined
Jul 2, 2016
Messages
2,611
So, my male G. pulchripies is currently in the middle of molting. I would put him at around d 4.5 inches before this molt. In doing a little research, it appears that males of the same species mature at different sizes. I've seen MMs at 5.5 and MMs at 7.5.

Really hoping he doesn't mature out on this molt. Regardless, the question I have has to do with varying sizes of MMs.

Is there any control that we as keepers can have on the outcome of MMs ultimate molting?

Does it have to do with breeding or more to do with feeding, and environmental controls?

BTW, my male is probably 3 years old and I haven't power fed him by any stretch of the imagination. 3-4(max) Crickets a week. View attachment 241656
I believe it primarily has to do with genetics and feeding, the temps play a role in how fast they grow as well. If your male is 4.5 inches he could very well mature next molt, there's no way of knowing for certain.

I'd imagine that Ts from different gene pools are likely to naturally vary in size. It's an interesting question that I have also wondered about, hopefully some research will be done on this eventually.
 

Sarkhan42

Arachnodemon
Joined
Dec 29, 2015
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737
It'd be interesting to see what actually does have an impact, but so far it seems to me to be relatively genetics related. I've produced both large and average males with a high temperature setup and frequent feeding (I'm a sucker for a nice hunting stance). My male GBB most recently ended up being very large for a male.
 

Gods Spartan

Arachnopeon
Joined
Jul 15, 2014
Messages
47
Interesting. I might ask the seller how big theirs turned out to be if genetics do play a role and he hasn't matured yet. Only three years roughly. Haven't seen him yet as I had to step out, but I will get an eye on him soon and post up.
 

Anoplogaster

Arachnodemon
Joined
Jan 15, 2017
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675
There is most definitely going to be genetic variation. Just look at people. Some don't even reach 5 feet at maturity, while others exceed 7 feet. Same species:)
 

JoshDM020

Arachnobaron
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Mar 24, 2017
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I feel like 4-3 crickets a week qualifies as power feeding for a T that size. Depending on species, i suppose. Most of the grammostolas, for instance.
 

korg

Arachnobaron
Joined
Feb 24, 2013
Messages
594
There is some inherent variation in the size of mature males for all tarantula species, which offers a pretty clear evolutionary advantage: when the males from a single sac mature at a wider range of sizes there is necessarily a wider "window" of MM availability in the local population.
I wonder, if you can have a MM larger than a MF if genetics do play a role.
Large ultimate males in some species can indeed be as large or larger than some of the technically mature females.
 

CEC

Arachnoangel
Arachnosupporter
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There is some inherent variation in the size of mature males for all tarantula species, which offers a pretty clear evolutionary advantage: when the males from a single sac mature at a wider range of sizes there is necessarily a wider "window" of MM availability in the local population.


Large ultimate males in some species can indeed be as large or larger than some of the technically mature females.
I agree...

All the mature females in my Neoholothele incei communal have a smaller DLS than the mature males. They have produced another generation so their maturity is proven.

Here is a family portrait. Olive MM & Gold Sling (left) - Olive MF (right)
2017-05-29 00.47.46.jpg
 

Gods Spartan

Arachnopeon
Joined
Jul 15, 2014
Messages
47
I remember watching a video by RobC. One of his Caribena versicolor females quickly overpowered the male he had attempted to breed her with. He mentioned that he had another MM that would have simply pushed her back if she had tried.

Anyway, my pulchripies is out of his molt now. Can't tell if he has hooked out yet. Maybe later today I can check in on him. Gonna let him rest for now.
 

Gods Spartan

Arachnopeon
Joined
Jul 15, 2014
Messages
47
Well, he hooked out. Haven't had a good look at him yet as he just now started to stretch out. He seems longer than my female, but thinner by a bit.
 

Gods Spartan

Arachnopeon
Joined
Jul 15, 2014
Messages
47
So there he is. Right in front of his water dish for size reference. What do you guys think? Is he a small MM or average?
 
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