Even if we are predisposed to be fearful of spiders, so what? Not all spiders are the same, and jumping spiders are certainly 100% harmless to humans of all sizes. Why not work on promoting that experience and rationality override any (often mistaken) primal urges that we have?
If you don't know anything about any wild berries, beyond some are poisonous, it might be a safe bet to never eat any of them.
If you know something about berries, like this species is definitely poisonous, and this species is definitely safe, and this species you don't know anything about, then it is perfectly safe to avoid the first and third and indulge in the second.
May be because of their unpredictability owing to their jumpiness? That seems very reasonable since humans do instinctually stay away from unpredictable organisms/animals in nature. That unpredictability doesn’t always have to correlate with the real dangerousness of those creatures.
