Live Bearers Have Sexchanges?!

[unknowntbeast]

OK I was just talking to the LFS person and she said that live bearers can change genders! Wouldn't that defeat the purpose of getting just males or females if they could change like that and still spawn?

 

[Amberleaf]

It's only that they change genders is when they are juveniles. XD In a large pack of fry, one alpha male will grow to be nice and large, so the *other* males will disguise themselves as females to avoid getting bullied. But, don't worry; they'll all decide on their TRUE genders EVENTUALLY!!!! ^^;

 

[Rediahs]

Well, if you are using the word "gender" interchangably with sex, don't, because they do not mean the same thing. I don't know that fish can have genders. Humans are the only animal that I know for sure can have genders.

As for their sex, I have heard that before too but I am really not sure if that's accurate or not. It sounds a bit far-fetched but at the same time maybe not. I don't know how fish are sexed.

Amberleaf: I am pretty sure whichever sex they are at the moment IS their "true" sex at the time, regardless of whether it changes or not... it's not like everything can only be male or female on a permanent basis you know. In our society we are very used to the idea that sex is immutable and permanent but it just ain't so!

 

[helterskelter]

No livebearers dont change sex. However some things do happen.

Old female swordtail/platies (Xiphophorus sp), sometimes get a hormone imbalance of testosterone which make the develop secondary (external) sexual characteristic.
This is the sexual organ of the male, the Gonopodium and in swordstails they develop a swordtail on the tail.

However they do not develop testes and cant produce sperm.
Thus resulting in them being unable to breed.

Young swords/platies/guppies/mollies and many of the other 300 species of livebeares and many egg layers may look mature, but as already described by Amberleaf, some males have a tactic where they stay immature for several months after the first fry matures and develops secondary (external) sexual characteristic's.
This to grow much larger and stronger then the other males which may be concentrating on breeding.
They then get develop the males characteristic and are the very best fish you can every keep being much more vibrant than the other's thus getting more chances to reproduce.

 

[OldMan47]

I almost agree with HelterSkelter on this one. The 300 must only be referring to freshwater species because otherwise the number is far too small. I have seen sneaker males among poeciliids but have yet to notice that tendency among the goodeids. That does not mean that it doesn't happen but I have not seen it. The most common livebearers that you will see in a pet shop are all poeciliids so I guess the observation will work for most people but I like to pick nits.

 

[helterskelter]

Yes oldman not noticed it in Goodeids either, but Poeciliids which was the main reference defo do.