Presumably, when preparedness for snake fear was being naturally selected, delaying one's fearresponse while one drew a distinction between poisonous and nonpoisonous snakes was not the most adaptive way to respond to the situation of suddenly coming across a snake.

… Cyril III ibn Laqlaq’s correspondence which reflects genuine—if intentionally vague—concern for the secretive community of Christian converts and reverts [who had converted to Islam before].

[…] no man was able to answer him a word, neither durst any man from that day forth ask him any more questions.

This true Man ſoon aſſembled him beforn: / Three Sons he had that ſtalwart were and bold, / And twenty Men of Kin in his Houſhold.