Breeding two different head colours

[BrettB]

Shane, I think that link is to a different study, but I have read the study you are eluding to.

Going back to the original post

yellow headed bird with a red headed bird all the offspring will be male

You would only need to breed a single hen with this pairing to prove it was false. So I think it is safe to say that it is FALSE.
That is not to say that you would get a 50/50 split of cocks and hens with such a pairing, that may not be the case.

Cheers
Brett

[Shane Gowland]

Shane, I think that link is to a different study, but I have read the study you are eluding to.

Good observation. It's not the correct paper, but it's from the same study. (Conducted by Dr Sarah Pryke)

You would only need to breed a single hen with this pairing to prove it was false. So I think it is safe to say that it is FALSE.

I was basing my response on the assertion of the video referenced, not Finnigan's interpretation from the first post.

[Tiaris]

My post stating that it is false is not based on a misplaced belief, but rather on fact. Mixed head colour matings produce females - fact. Any "scientific" study, peer reviewed or otherwise, which states anything to the contrary is simply false. In recent years most of my own Gouldian pairings have been deliberate mixed head colour pairs: results for the last 4 years are 3 with extra hens & 1 with extra cocks over a couple of hundred birds bred. Also experienced slightly better clutch size with my mixed head colour pairs compared to same. I strenuously doubt any research which hastily draws species-wide conclusions based on short-term research in one captive collection especially when it is totally inconsistent with the life-long experiences of many individual private breeders.

[E Orix]

All I know is if I breed the same colour headed birds together(Red) I get far better(Red) head colour in the hens heads.

[finchbreeder]

All I can say is that it does not seem to make a blind bit of difference with mine if the pair have the same or different head colours as to the sexs, still get about 55% male and 45% female. But I have also noted that the hens have better head colour if mum and dad have the same head colour.
LML

[Denozo]

Without eeading the paper it is hard to comment however the sample size in the attached paper is large enough to detect a significant difference in a given sample. They could therefore conclude in their sample that there is a gender inbalance. However, this shouldn't be extrapolated to the entire population of gouldians. The inbalance could be as small as a single bird more being male

[Shane Gowland]

Any "scientific" study, peer reviewed or otherwise, which states anything to the contrary is simply false.

It's a shame you're so comfortable with that fallacious logic, because conscious sex selection among Gouldians is a fascinating topic that is worth discussing.

[Tiaris]

In what way do you believe I have been fallacious? The proposition that mixed head colour Gouldian pairings produce only male progeny is unambiguously and undeniably false.
I totally agree that the topic of sex selection in gouldians is fascinating and very worthy of discussion.

[Shane Gowland]

The proposition that mixed head colour Gouldian pairings produce only male progeny

That's not what the study, the paper or I are asserting: just that there's a strong preference for one particular sex when head colours are mismatched, and that the hen is able to somehow decide the gender preference.

[iaos]

I'm also guilty of not reading the paper, but I have a memory of my the conclusion being that a higher percentage of males would be bred, not only males...