Guppy experiment

[Trainer_Ruby_]

My fancy guppy dropped fry about a week ago and I wanted to test a theory. There are articles that say guppies can change gender as needed in their environment so I'm testing that. I have 1 in a 10g betta tank because bettas leave female guppies alone so far looks female. I also put 2 in a 20g to get a male and female one is starting to get color


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[Fishdude3233]

My fancy guppy dropped fry about a week ago and I wanted to test a theory. There are articles that say guppies can change gender as needed in their environment so I'm testing that. I have 1 in a 10g betta tank because bettas leave female guppies alone View attachment 269102 so far looks female. I also put 2 in a 20g to get a male and female View attachment 269103 one is starting to get color


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so your theory is that the guppy in the 10 will be a female, and the two in the 20 will be 1M-1 F?

 

[livefishguy124]

sorry but i'm 100% sure they wont change. people think they change but they don't. when fry are born they look like females, they are dull colored, and they don't have gondulums, all the fins are fan shaped, like a females, but the males will begin to develop there "male" trait's after a month or so, depending what you feed them and their tank equipment and parameters. so they don;t change gender they just confuse us for a little while.

 

[Mebbid]

Guppies cannot change gender. I looked for information to back this, but this was the only article I could come up with. Which involves a change of gender numbers that are birthed.

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I would imagine a lot of this rumor comes from the fact that guppies can store sperm to use for up to 3 to 4 months in multiple different batches of fry.

It would be weird to buy all females and see one suddenly get pregnant. It would give birth, and potentially give birth again after that first time. By that time, the males from her first batch are sexually mature keeping the breeding going on. That alone would give rise to the myth that guppies can change gender.

 

[Fishdude3233]

just as a clarification, by saying what I did, I did not mean to imply I was agreeing with him. just wanted to make sure that I understood what he was trying to accomplish.

 

[Trainer_Ruby_]

From what I've found a guppys gender is undefined in the early stage of life so after 2 days old I started the experiment. The worst that'll happen is a male betta with a male guppy but my betta is extremely laid back and has done good with mollies and guppies before so there's no real threat to any things life


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[TMRC Exotics]

No their genders certainly are defined and with a flashlight and a good set of eyes you can sex them from as soon as they are swimming. Breeders separate juvies in the first 4 days to prevent accidental pregnancies. Not trying to be rude(seriously want to emphasize that) but your theories are incorrect.

 

[Trainer_Ruby_]

Question is it more common to have more female than male? The last couple of groups I've had all female with one or two male


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[TMRC Exotics]

I usually saw around a 60/40 split with more females but I also had a lot of near 50/50 numbers.

 

[Trainer_Ruby_]

Mine are typically 90/10 female to male



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[TMRC Exotics]

Mine were never skewed that far female. I imagine a lot of things could come into play here, genetics, conditions, it may be completely random.

 

[Fishdude3233]

mine are 60/40 F/M, but I wish I had 70-80 percent females.

 

[livefishguy124]

i think that temp and pH play a role in the fry's gender

 

[TMRC Exotics]

See if you can find a link on that. Would be interesting to see if that is supported. I know temperature is a factor on egg laying reptiles, never knew if that applied with live bearer fish, or egg layers for that matter.

 

[livefishguy124]

Re: Sex Ratio "Experiment"

 

[TMRC Exotics]

That appears to be suggesting that species was altering its gender based on population in its clutch.

I was looking for something related to temperature etc effecting guppies

 

[livefishguy124]

"Yup. The biggest effect on the gender of fish is the water temperature they are born in. It has been reported on several occasions by multiple tests that higher temps will produce more of one gender and lower temps will produce more of the other."

heres the site
What Determines Gender in Guppies? [Archive] - Aquarium Forum

 

[livefishguy124]

Does temp. affect sex of baby guppies? [Archive] - Aquaria Central

i think that there is a lot of theory to this but not much proof. i think we should get a groop of people and try to do this, see if pH or temp does affect it.

 

[TMRC Exotics]

"Yup. The biggest effect on the gender of fish is the water temperature they are born in. It has been reported on several occasions by multiple tests that higher temps will produce more of one gender and lower temps will produce more of the other."

heres the site
What Determines Gender in Guppies? [Archive] - Aquarium Forum

I read through both of those and there is absolutely nothing supporting it. Just 2 random individuals suggesting it in a forum just like this. This above quote is in its entire context and is an opinion not any sort of factual statement with evidence.
I don't mean this in a bad way, thanks for looking them up. There just isn't anything in those to support the theory either, just a few people inferring it. It would be neat to test. If done do it properly with the whole scientific method and we can put it up to a peer review here on aa, try to replicate it. I'm in, lol, but I digress. Getting off topic.

 

[Trainer_Ruby_]

I may try that experiment being guppies give birth once a month and I have 2 female that are pregnant so I'll have to give it a try


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