I was wondering if anyone else has ever heard of this happening. It has me baffled.
I moved two very young guppy females into a tank that had only had shrimp and dwarf cory catfish in it previously, to keep a light fish load in it while I moved some tanks around. This tank has basically been in a holding pattern, and for much longer than I anticipated. It is planted with crypts and some Hydrocotyle, and is a Walstad-style planted tank.
Anyhow, these were VERY young female guppies, and this was MORE than 6 months ago. Neither has changed into a male (yeah, I've had that happen where a young female will "become" male if no males are present) and now suddenly there are two newborn fry swimming around with them! Both adults are still female in appearance, but look like they might just drop some more fry.
This is odd. Can they "hold" genetic material from a male for 6-7 months? I didn't think that was possible, and really, both females were so young when I brought them over that I figured they had not bred yet.
Also, will these fry be "normal"? I'm actually a bit curious to see if these develop into males or females. My guess would be they'll be male.
Thanks very much!