Isn’t it more that it is just extremely difficult if not impossible to do the necessary longitudinal study in humans? You’d need verified quantified early traum

Isn’t it more that it is just extremely difficult if not impossible to do the necessary longitudinal study in humans? You’d need verified quantified early trauma, lack of possible TBI, and early death, and RNAseq processing postmortem which is a recent development. I think about it evolutionarily: if an animal was subject to significant early trauma (i.e. divergence from expected early environment), the most likely cause is early loss of a parent and no surrogate caretaker. This suggests a markedly different environment generally, and especially socially, and would warrant a significant behavior shift if it were evolutionarily possible to accomplish. It doesn’t seem so implausible to me.