Can fish change sex?

[noodles62]

I have several zebra danios, one of which I was CERTAIN was a male, (very long and slender compared to others w/fat bellies). Now as of today, he (?) also has a fat belly as if full of eggs? Is this possible or was my original ID just wrong?
Weird!! :eek3:

[Dwarf Puffers]

Danios do not change sex. It is either a fat male or a skinny female. Off the top of my head, the only sex changers I can think of are SW fish, like clowns and some anthias.

[Sarge_857]

frogs i know change sex in a single sex community. (Jurassic park. Need i say more?)

[wataugachicken]

i would take a closer look and make sure that it's not dropsy. . . this is swelling of the fish's body that in later stages causes the scales to stick out like a pinecone.

[cam191919]

never heard of any freshwater sex changers

[crazycanuck]

bees can change sex .. learned that in science last week :) lmao far as i know danios cannot

[THE V]

There are several different protogynous freshwater fish.

http://www.jstor.org/pss/1448239

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6WXF-4CGM8H3-1&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=f5a51056d3f50548bbfefcded8545509

http://content.karger.com/ProdukteDB/produkte.asp?Aktion=ShowFulltext&ArtikelNr=000074348&Ausgabe=229737&ProduktNr=224037

[TwoTankAmin]

Female swordtails can change sex to male. This normally occurs when there are no males.

[noodles62]

Well, this morning he looks like a male again. I think he just gorged on flake food last night. Poor tank mates are prob starving with this guy around! Thanks for the input; I will keep on eye on him and make sure it is not anything to be concerned about.....it just looked so wierd - just like the females w/ eggs!

[KarlTh]

Female swordtails can change sex to male. This normally occurs when there are no males.

They can't. Late developing males often appear female although apparently full grown, and old females can grow swords and even a gonopodium, but there's no recorded case of a functional female turning into a functional male.

[Marinemom]

They can't. Late developing males often appear female although apparently full grown, and old females can grow swords and even a gonopodium, but there's no recorded case of a functional female turning into a functional male.

Actually I have seen this sex changing thing happen with my sword tails in the past in my very own tank. The male dies so the dominant female takes on the role of the male if another male is not introduced into the tank in due time. Now weather or not this fish was actually a female that changed to a male without the presence of a male or it it as you said and the fish was just late in the development of the sex organs I do not know. All I know is it seemed very odd to me that that kind of thing could even happen in nature.:confused:

Marinemom

[noodles62]

Kinda creepy!!

[KarlTh]

Actually I have seen this sex changing thing happen with my sword tails in the past in my very own tank. The male dies so the dominant female takes on the role of the male if another male is not introduced into the tank in due time. Now weather or not this fish was actually a female that changed to a male without the presence of a male or it it as you said and the fish was just late in the development of the sex organs I do not know. All I know is it seemed very odd to me that that kind of thing could even happen in nature.:confused:

Marinemom

Or it may be a female which developed male characteristics, in which case it would not have been a fertile male. The point is, no-one's actually documented a female which has given birth to fry turn into a male which has then fertilised females - i.e. a true sex change. Apparent females turning into males, and/or females turning into apparent males, yes, seen it myself.

[THE V]

Or it may be a female which developed male characteristics, in which case it would not have been a fertile male. The point is, no-one's actually documented a female which has given birth to fry turn into a male which has then fertilised females - i.e. a true sex change. Apparent females turning into males, and/or females turning into apparent males, yes, seen it myself.

It is documented but it appears to depend on the strain. This was published in 1979...

http://www.springerlink.com/content/k655j62744u57m24/

[KarlTh]

That link's confused though - is it protogeny or hermaphroditism?

[The Zigman]

I wish i could change sex, just long enough to understand what the heck my GF is talking about 94% of the time!

And it wouldn't be so bad is someone bought ME a drink once in a while!

(then later, I'd change back in the bathroom, and sneak out!)

[sillypony]

zigman.. that sounds like mrs doubtfire?? lol

[LvTaraMae]

I didnt even know fish (or anything for that matter) could change their sex........werid.....