Sling gender hints

[justanotherTkeeper]

So, I know it is very difficult (if not impossible) to sex slings smaller than 3/4-1" DLS

BUT there are a few indicators the experienced eye can sometimes spot - such as the growth rate. The theory is; when you have say, 2 to 4 (or more) slings from the same egg sac, you likely have some of each - boys and girls. If you monitor their growth, some of these slings will molt more often and grow faster than their siblings, despite providing all the same care, conditions, and feeding routine.

@Thawn139 posted about this once, affectionately deeming it the "S.W.A.G. approach" lol. Basically, the ones molting and growing faster would likely be males, and the slower growing slings are likely females.

Right?

So here's what I'm wondering... I got two 1/2" E. weijenberghi slings couple months ago, both same size and from same seller. I do not know for sure they are from the same sac, but circumstantial evidence says there's a good chance they're siblings. One molted 9/16, and the other molted today 10/30.

Given this is a slow-growing dwarf species, is this not a significant enough gap between molts to guess that today's T is a girl? It's very early to try using this method to make a gender guess, I know, but I can be a stubbornly impatient person lol.

Any opinions or additional information is welcome

 

[The Grym Reaper]

Basically, the ones molting and growing faster would likely be males, and the slower growing slings are likely females.

Right?

Nope, there are far too many factors that affect growth rates

 

[moricollins]

No direct correlation between growth rate and gender. Males can grow faster than females. Females can grow faster than males. No rule about which gender grows faster, even within a single species.

 

[viper69]

So, I know it is very difficult (if not impossible) to sex slings smaller than 3/4-1" DLS

BUT there are a few indicators the experienced eye can sometimes spot - such as the growth rate. The theory is; when you have say, 2 to 4 (or more) slings from the same egg sac, you likely have some of each - boys and girls. If you monitor their growth, some of these slings will molt more often and grow faster than their siblings, despite providing all the same care, conditions, and feeding routine.

@Thawn139 posted about this once, affectionately deeming it the "S.W.A.G. approach" lol. Basically, the ones molting and growing faster would likely be males, and the slower growing slings are likely females.

Right?

So here's what I'm wondering... I got two 1/2" E. weijenberghi slings couple months ago, both same size and from same seller. I do not know for sure they are from the same sac, but circumstantial evidence says there's a good chance they're siblings. One molted 9/16, and the other molted today 10/30.

Given this is a slow-growing dwarf species, is this not a significant enough gap between molts to guess that today's T is a girl? It's very early to try using this method to make a gender guess, I know, but I can be a stubbornly impatient person lol.

Any opinions or additional information is welcome

That SWAG is garbage.

Just wait like everyone else

 

[thatdadlife619]

No direct correlation between growth rate and gender. Males can grow faster than females. Females can grow faster than males. No rule about which gender grows faster, even within a single species.

If there’s never been any direct correlation, why is there so much heavy opinion out there that females ALWAYS grow slower than males? I always keep an open mind in this hobby, I’m just curious why so many keepers believe it to be true

 

[moricollins]

If there’s never been any direct correlation, why is there so much heavy opinion out there that females ALWAYS grow slower than males? I always keep an open mind in this hobby, I’m just curious why so many keepers believe it to be true

Because people will believe whatever they're told...

I have yet to see a scientific paper linking growth rates to gender in tarantulas.

There are lots of anecdotal reports on this forum from people whose females grew faster than males (from people who have 5-10 slings from the same egg sack), and vice versa.

 

[Liquifin]

Other than what kind of species it is, sex or gender of a spider has nothing to do with growth rates. I think people need to understand that every tarantula is a unique specimen just like every person. Not every person grows at the same time or rate and it should also be applied to tarantulas as well.

I think people should be happy enough to enjoy what species they have and not worry about what sex it is. People are too desperate for females these days which many of those keepers completely ignore how rare a male is. Yes, I know a male is not long lived, but just wait until he's mature then you'll see the true value for a male. I see more females for sale than males, so that's saying something.

 

[cold blood]

Basically, the ones molting and growing faster would likely be males, and the slower growing slings are likely females.

Right?

wrong

I see this absolutely false speculation all the time...raise enough slings and you will see the theory holds no water.

In fact, often the opposite is often true with females out pacing males...in fact, i find the slowest growing, runty slings to most often (but not always) end up to be males.

Fact is, some males grow faster than average, others slower, others right in line with norm....and the same can be said with regard to females.

I’m just curious why so many keepers believe it to be true

because it keeps getting repeated, plain and simple....thats how misconceptions get wrongfully accepted....it gets repeated, then it gets assumed to be true.

 

[Vanessa]

If there’s never been any direct correlation, why is there so much heavy opinion out there that females ALWAYS grow slower than males? I always keep an open mind in this hobby, I’m just curious why so many keepers believe it to be true

Because some people really do experience that - they have a small amount of tarantulas and it definitely has been part of their experience that the males grew faster than females. Males can grow faster than females in some cases... just not enough to say that it is a sure bet that you can determine sex by growth rate.
You see that it is not a reliable gauge the more tarantulas that you have of different species. If I looked at my collection, and took some of the most popular species in the hobby - Avicularia avicularia, Grammostola rosea/porteri, Brachypelma - and compared my males and females, my males grew faster. However, if I look at some of my other species - the Thrixopelma, Tliltocatl, a good percentage of my dwarfs, the Bonnetina, the Euathlus, some of the faster growing Grammostola - a good percentage of them had males and females grow at pretty much the same rate and some where the females even grew faster.
It isn't that males don't grow faster than females, because they do in some cases, it's that it is not consistent enough to use growth rate as a reliable sexing tool.

 

[lazarus]

BUT there are a few indicators the experienced eye can sometimes spot - such as the growth rate. The theory is; when you have say, 2 to 4 (or more) slings from the same egg sac, you likely have some of each - boys and girls. If you monitor their growth, some of these slings will molt more often and grow faster than their siblings, despite providing all the same care, conditions, and feeding routine.

This is just a legend in my experience and I usually buy slings in groups of 3/5/8/10. The source for this legend I think is the fact that males reach maturity in fewer molts than females.
But you can sex slings with a microscope, 5th or 6th instars are usually sexable with a fairly affordable microscope.

 

[Smotzer]

I find that sexing them is often a pretty good indicator and thats about it.....