Has anybody done any research on whether foetus development in roe deer is dictated at the point of fertilisation or at some slightly later stage of development due to selective hormone secretion by the doe?
I was sure it was the sperm that dictated the sex of the foetus/zygote at the point of conception but wondered if there had been any research into this for roe deer.
I know that 'male' sperm swims faster than 'female' sperm but that 'female' sperm is more long lived than XY (male) sperm.
I was having a discussion recently about roe deer populations and their ability to produce young of a sex appropriate to the local population densities of the sexes. i.e low in does=twin does, low in bucks=twin bucks, equilibrium=twins, one of each sex, and wondered if the doe released more oestrogen, progesterone, testosterone at the time the sperm is transferred or at the time the zygote descends into the womb?