What neurobiological correlates are implicated by a potentially lethaly persistent stressor that can't be muscularly evaded? stimulation

A couple of almost identical leading (not rhetorical but ~rEPTilian)
questions:

What adaptive neurobiological correlates are implicated by potentially
lethally persistent stressors that can't be escaped by way of kinetic
activity by any kind of muscle(s)?

Hence (IOW), what phenotypic characteristics does real lifetime examples of
this particular (broadly defined) class of selective pressures tend to
select for?

[Who knows, someone who get even just the tiniest whiff of the possible
answer to the above question(s) might be close to halfway on the way to
acquiring an exceptionally powerful theoretical 'ahaa-like association'.]

P




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