There has been recent work into whether the ratio between a man's ring and index finger is indicative of the levels of testosterone that he was exposed to in the womb, and the researchers claim that this can also give us an indicator of his fertility, liability to heart attacks, depression etc, sporting ability etc.
However, I was wondering if anyone could elaborate on the importance of womb testosterone exposure. Is a man's fertility really set from the levels of hormones which he was exposed to in the womb, as I'd have imagined that later exposure (like the levels at puberty) would be more important - or are the levels of testosterone that a man is exposed to later in life also decided by the exposure in the womb?
Can we actually expect to believe that a man whose idex finger is longer than his ring finger to be 'less of a man'? Surely it is the testosterone which he is exposed to during life which is more important? Or can testosterone later in life (e.g. during puberty or taking artifically) not have such a profound fact on physical characteristics?
If we think of a man or boy who has an index finger that is longer than his ring finger is it really likely that throughout his life he is likely to be less fertile, more at risk from heat disease, less likely to make a top sportsman. Even if this particular male received higher amounts of testosterone during puberty than a male who had the favourable finger ratio?
What I'm really asking is if foetal exposure to testosterone is as important as Manning etc. make out, or if exposure later in life and at puberty is important (or is this too based on foetal exposure?). Can we expect males who had low womb exposure rates to be more likely to suffer from low testosterone levels in future? Does womb exposure have enough of an influence to make some men less 'man' than other men, or is it what happens after birth?
Would the all important penis size, for example, be based on womb exposure, or puberty exposure? Or are genetics far more important in general than womb exposure?
I'm partly asking this because the research (I know it is still fairly new and only lightly touched upon) seems fairly misleading. Why should the high testosterone ratio give higher chances of homosexuality if it also gives 'perfect alpha man' characteristics, and why does it differ depending on where peoeple are geographically located?
Thanks for any replies, I do find this topic interesting, and would love to hear some educated (or otherwise!) replies. I hope you don't find my ramblings too vague/un-scientific to follow
Any info on womb testosterone exposure and effects/lack of effect on later life I'm interested in.