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Are boy embyos or fetuses sturdier than girl ones?
There is exactly a 50% chance of a father passing an x chromosome as a y, yet there are slightly more boys born into this world than there are girls. In spite of this there are more women on this planet than men. We know that females are built sturdier as they out live men. I would imagine that has something to do with having to withstand pregnancy and childbirth.
So why the higher male birthrate?
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