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There's a Logic To How Squirrels Bury Their Nuts (berkeley.edu)

sandbagger shares an announcement from the University of California: Like trick-or-treaters sorting their Halloween candy haul, fox squirrels apparently organize their stashes of nuts by variety, quality and possibly even preference, according to new UC Berkeley research... Fox squirrels stockpile at least 3,000 to 10,000 nuts a year and, under certain conditions, separate each cache into quasi "subfolders," one for each type of nut, researchers said... Over a two-year period, the research team tracked the caching patterns of 45 male and female fox squirrels as the reddish gray, bushy-tailed rodents buried almonds, pecans, hazelnuts and walnuts in various wooded locations on the UC Berkeley campus...

Using hand-held GPS navigators, researchers tracked the squirrels from their starting location to their caching location, then mapped the distribution of nut types and caching locations to detect patterns. They found that the squirrels who foraged at a single location frequently organized their caches by nut species, returning to, say, the almond area, if that was the type of nut they were gathering, and keeping each category of nut that they buried separate. Meanwhile, the squirrels foraging in multiple locations deliberately avoided caching in areas where they had already buried nuts, rather than organizing nuts by type.

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  1. Cache Security by mentil · · Score: 4, Insightful

    Let's say a competing species is able to smell almonds, but not other nuts. If all the almonds are separated into their own cache, then the competitor would only be able to sniff out the squirrel's almond cache, leaving their other nut caches safe. However, if they mix almonds in at all of their caches, then the competitor will smell the almonds in all of their caches, and thus find (and eat) all of their cached nuts. Separating the nuts thus prevents them from putting all their eggs in one basket, and the squirrel is less likely to starve because all its nuts were stolen. Those who sort their nuts survive and reproduce, those who don't die, et voila evolution.

    --
    Corruption is convincing someone that the selfless ideal is the same as their selfish ideal.