== Maternal Sex Determination vs Wikipedia's article on Male XY determination == 

 This article seems to completely contradict the article in Wikipedia about the XY chromosome determination of gender. Also, it states as if it is a definite point and proven past the point of being a theory or hypothesis but it doesn't seem have any proof. The other wikipedia article I read about the Male XY chromosome and the SRY gene seems to completely contradict this article. Furthermore, there are so many more other articles that go back in history in regards to 'observation' and 'populations' as well that doesn't seem to back this article up at all. If the male doesn't contribute the Y chromosome for the female XX chromosome, then it would have to be proven without a doubt that the pellicuda could block the Y chromosome completely and select the X chromosome but I didn't see where this was proven. It has been stated in the wikipedia article about the male XY chromosome that the male either contributes the Y or the X, so how does the female body prove it can reject the Y and then the X will thus be contributed in turn from the male chromosome? Has that been observed and proven? Again, this article seems to be a huge contradiction and also what has been stated doesn't seem to have been backed up by a theory that has been proven.    https://en.wikipedia.org/wiki/XY_sex-determination_system