But a 3 year old has ALREADY been heavily influenced by the modeling of the parent, so I'd think we'd need to go back earlier than 3 to see whether this is biologically rooted. Even though the pre 3 child might not be easily tested in this fashion, although they might have difficulty understanding the questions, and some may be pre-verbal, it doesn' mean that a test shouldn't be designed to test for earlier attitudes and imprinting.

Also did she control for ethnic variations in child rearing? If so, that would point a little closer to having a biological component. Even still, females are treated very differently than boys across many cultures. Even those trying to give girls a strong healthy sense of self, are taught through subtle cues from the most egalitarian of parents that they need to watch out for certain realties ..(getting pregnant, being raped,etc)...and yes, males have other threats from their environments. But there is a confidence modeled for boys, a belief in the ability to overcome their challenges, meet them, in a way that many girls are not, and are instead taught to be wary/cautious as prevention.

Did she distinguish how girls and women react to events that were purely emotionally challenging, vs a purely physical threat ?

The heightened fear of physical threat makes sense from an evolutionary perspective, with females being more vulnerable physically, so perhaps those who predicted the future based on past would be more prepared to counter future threat as a result of increased worrying... an adaptive advantage to worry...