+The coincidental conjunction of a friendship-forming instinct, a novel-secret-seeking instinct, _and_ a nearby distinct subspecies with similar properties, led to some unusual behavior patterns. Given the different survival-relevant opportunities in their respective habitats, each subspecies predominantly hoarded _different_ secrets: the secret of how to jump and land on the thinner branches of the reedy pilot tree was of little relevance to the daily activity of a west-valley ground squirrel, but the secret of how to bury nuts without making it obvious that the ground had been upturned was of little import to an east-valley tree squirrel.
+
+But the squirrels' _novelty-seeking instincts_ didn't track such distinctions. Secrets from one subspecies thus functioned as a superstimulus to the other subspecies, on account of being so exotic, thus making cross-species friendships
+
+[TODO: but species differences also make them frustrating]
+
+At this, some extremely naïve novice students of historical mammology inquire: [TODO ...]
+
+To which it is replied:
+
+A few particularly naïve students inquire further: [TODO ...]
+
+To which it is replied: there's _no reason whatsoever_ for evolution to select for that, _dummy_. What's wrong with you?
+
+And so, many, many times in the days of auld lang syne, a squirrel in a burrow or a tree would sadly settle down to rest for the night, lamenting, "I wish I had a special friend. Someone who understood me. Someone to share my secrets with."