False gravid spot?

[Synirr]

I've discovered that one of my male feeder guppies can change colours and make a patch of black pigment appear on his side... and it looks exactly like a gravid spot. Could this have some sort of evolutionary value, like parasitic breeders (aka sneaker males) that look like females to avoid competition from other, normal males? Anyone know anything about this? I think it's very interesting... I'm going to have to watch and observe his behaviour in the future when he makes the spot appear.

This is the same male whose tail is in front of the black rock in this pic... this is what he normally looks like:

 

[Sandamarly]

Alot of my males have that as well. I dont think its to do with a gravid spot though most probably colouring or food they have eaten or even waste!!!

 

[guppygirl]

Yeah, I had a male a while ago that had coloring there that I sware looked like a gravid... but he had a huge red tail so that didn't really work!!

 

[Synirr]

Alot of my males have that as well. I dont think its to do with a gravid spot though most probably colouring or food they have eaten or even waste!!!

It's definitely colouring, because I've watched him fade it in and out... I just find it a little coincidental that it looks almost exactly like a gravid spot. I was thinking it might have some sort of use, like fooling other males or something... but that's just me