Guppies change sex?

Question

I need some help!!

I recently heard that guppies can change sex. I am very interested in this and i have decide to do my science fari prohect on it. does any one have any info on how, why ect. they do this??
thank you

Answer 1

guppies are capable to change their sex. studies said that only female guppy are capable of it and it takes a long time. if you would like to use it as your science project, i don't know if you can really prove that to class. in a tank put some guppies preferrably all females. and sex change occures when all female guppies are fertile and ready for mating. once tese occur, one of those will change sex to fertized but these happens unnoticeable.

Answer 2

I have had guppys change sex. In a small tank by my bed I stocked with two females and a male. The male died shortly after arriving. Both females remained healthy but not pregnant. You can tell when a guppy is expecting by the gravid spot at the start of the tail. The females both had triangular ventral fins (the fin of a female guppy). Having had no male for 8 months my yellow female has transformed into a male. Complete with gonopodia (in the mail guppy the ventral fin forms a straw type penis, gonapodia). This appendage has all the mobility of any other frisky guppy male. My still female, female is now gravid (pregnant). I have observed however, the female whom has become a male is nowhere near as frisky as a birth male.
I have kept many fish in both home and commercial situations for many years but I still think guppys are a fascinating little fish.

Answer 3

No hard proof, but there's never a definite answer to almost everything, especially with Life!

No, for all these years of keeping Guppies, they don't change sex!

But I've seen Red Sword-tail that changed. Maybe they just that mature and show their male's sword-tail at different ages.
Once they grow their male's sword tail, they hardly grow any bigger.

There are record of certain marine fishes which changes sex when the Alpha-Male dies.

There are also Marine fishes which are born all Female, then changes to Male when needs arise.

Answer 4

I've seen lots of answers, but no supporting sources. I tried Googling a few keywords ("guppies changing sex", "guppy gender change", etc.) to see if I could find any information for you.

All I was able to find were the following:

1) a forum question asked by a person who was told this by an employee at PetSmart (http://www.tetra-fish.com/forums/showthread.php?t=447) - other forum members replied this was for swordtails and never heard of this for guppies.

2) forum questions that were resolved by info that female guppies are capable of storing sperm from males and being able to give birth up to 6 months later (which is true!) - it's the 6th question (yellow block; a little more than halfway down the page: http://www.aquariumfish.net/catalog_pages/livebearer_guppies/guppies_page_1.htm

3) changing the sex of guppies in a "virtual" fish tank: http://members.fortunecity.co.uk/coxdon/FisherMan/splicing.htm

If anyone else has factual evidence (not hearsay) of this happening, maybe they should post their source - I can't find one!

Answer 5

I have never heard of guppies changing sex. I have heard of platies "changing sex". Like everyone else said its always female to male. The most likely explanation of this is simply a late maturing male. The fish was always a male but it didn't develop a gonopodium until later on. It does not actually change from a female into a male.

Answer 6

I have not heards of it happening in guppies, but platies and sword tails are well known for this. It only happens when female turn to males, not the other way around. So get a tank and put in 4-5 female platies.

I'll see if I can find some documentation of this occurance. I have never heard of it in guppies but I know for a fact it does happen in swordtails and platies.

OK after a quick search I found that there is tons of scientific documentation out there about platys(Xiphophorus Maculatus) changing sex. You have to pay for most of them to view the actual document unfortunatly, since you are doing a science project yourself, it may be worth it to you to buy a copy of a couple of the documents.

I went on google and search for "Xiphophorus Maculatus sex change" You will find all kinds of stuff

Answer 7

Ive had this happen with swortails and platies at home but havent seen it in guppies but that doesnt mean it isnt true ..also other fish such as in some wrasses when the dominant male in a teritory dies the largest female usualy changes sex and takes over the area (this has happened several times with the spoties at the aquarium i work at)

Answer 8

Many aquatic living thing sexes besides can receive the environment the influence, in life history each kind of stage, perhaps

The role acts which in the community when is different, also handles jointly with now and then the change to have the sex change phenomenon, is called

Natural transformation (Sex Change). The natural transformation phenomenon is quite common in certain 類群 fish, as a result of female fish

Or the male fish contour characteristic like body color 或體 on has the enormous difference much, therefore often is mistaken for does not belong

With type. Actually does the natural transformation natural phenomenon have what influence to these living thing? In the line in is or in the ecology

Has what kind of significance? Although the present understanding was still limited, actually also was the kind makes one feel the interesting marvelous ecology.

The natural transformation type generally may divide into: The monoecism, 雄性先熟, the female are first ripe. So-called monoecism

Is refers to certain fish to be allowed to have two kind of sexes in its life history, like deep sea female celestial fish, sharp mouth 鱸 and so on. But

雄性先熟 other longer sees the situation is, 生殖腺 the growth has the order change, is called gradually does

With monoecism. Kind is the male gender 生殖腺 first grows maturely, after the female 生殖腺 grows. But in addition

A kind of fish in the life history early time all is only the female fish, only then transfers the milter afterwards, then called the female is first ripe.

Answer 9

I have had a female that changes into a male and now have a male that just got pregnant. The fish was most defiantly a male with the gonopodia and lots of color and long fins. There are plenty of females, so I'm not sure why this little guy did it??? At first I thought he was over-eating and even separated him for a day, but then realized he/she was pregnant from the shape of the belly and the gravid shot starting to appear on the anus.

Answer 10

This is acutally 100% false the females do not change gender. In fact what happens is that females have a glan to hold sperm. If they have ever encountered a mail ((all pet stores store male and female fish together when very young which leads to pregnant fish)) they can hold the sperm for as long as they need.