My wife has lower then normal for women testosterone levels, but she always have been a bit less girly then other females (in behavior, not looks). She felt for example that she had little to no maternal instincts after giving birth to our child.
However testosterone and estrogen (and progesterone) pretty seriously affect the mind. There are very real effects beyond just placebo.
Higher levels of estrogen do generally make emotions feel more intense and lower levels of testosterone generally would make someone less likely to engage in a conflict.
Hormones don't really change your core personality though. I dbout someone would become less interested in something like tech because of a change in hormone levels. However, you might be more likely to pursue emotionally fulfilling careers and hobbies in the future, and I think in arrogate this could be what accounts for some of the sex differences we see in male / female career paths. As you mentioned, estrogen make emotions more intense and it seems likely to me that this might in part explain why women seem to enjoy social careers more - perhaps because they provide more emotional stimulus.
Neonatal levels of hormones probably have a larger role in shaping our core personalities though. One example of this would autism spectrum disorders which tends to make people more interested in "things". There is now some evidence that autism is a product of irregular hormones levels during development.
Do “maternal instincts” exist in the first place, and how do they differ from just parental instincts?
Explaining a failure to bond with your child through gender seems very questionable to me.
In some mammals, fathers have literally no contact with their offspring while mothers care for them for years (eg, bears). In others, the mother and father both remain as part of a pack, but the mother does all of the direct care and the father is doing hunting or protection. In some, the father may have a minimal role in early life but then become more involved later as their offspring learn to hunt or fight.
The social construct of both parents having equal and identical roles in parenting at all stages of child development is very new and very culturally unique to Western, industrialized and affluent societies. Across all primates and all evidence of pre-industrial humans, maternal and paternal roles were very different.
So, it is simply not true “across all” anything. I will forego badly parroting what actual experts say, so instead I recommend Robert Sapolsky’s lectures on this in his biology courses at Stanford. They’re available on YouTube.
I also notice you just vaguely referred to various animals in instead of humans, which is curious.
My position here, to be clear, is that there are gender differences in personality and phenotype, but they are mostly inconsequential for child rearing in a resource-rich society, ie, both genders are equally competent parents. Individual variation outweighs gender differences.
Intentionally so, because humans are animals and that's an imaginary distinction. Modern western society likes to pretend like we're these abstract minds that are attached to bodies. We're not, we're primates, only a tiny bit different than our ape cousins.
If you want to stick to humans, for about 99.9999% of the 315,000 years humans have been around, no mother was pumping breastmilk and sticking it in the refrigerator so that the father could do the 4am feeding.
Your comment is essentially putting a causal arrow backwards. Biology and nature would have us behaving in far more strongly differentiated gender roles. Contemporary western social norms and modern technology allow us to go against that nature. "Maternal instincts" are as real and fundamental as any other survival instinct humans or any other animal experience.
But please don’t let “human is just smart monke” turn into some naturalist fallacy wherein men must be manly because we were made so. We weren’t, but given a stressful environment, we CAN turn out that way.
It seems rather unscientific to make such baseless claims about a very specialised area most people don't have knowledge of, and mentioning anecdotes about your wife is totally irrelevant...
The other is an assumption that someone's observed characteristics are caused by one particular hormone level, with no evidence to support that.
You could attribute her height and preference for fatty fish to her T levels too, if you strained hard enough.
But this is subject to placebo effect, as the OP said, so you can't directly infer a casual influence on behaviour.
> The other is an assumption that someone's observed characteristics are caused by one particular hormone level, with no evidence to support that.
The OP did not say the lack of maternal instincts was caused by lower than normal testosterone, they simply noted that she had both characteristics.