WEBVTT - How Do Squirrels Organize Their Nuts? 0:00:02.040 --> 0:00:07.000 Welcome to brain stuff from how stuff works. A brain 0:00:07.040 --> 0:00:10.719 stuff is Christian zagger. Here. Despite how common North American 0:00:10.760 --> 0:00:14.440 tree squirrels are in many cities, neighborhoods, and outdoor spaces, 0:00:14.560 --> 0:00:19.239 a big misconception exists about these little critters. Tree squirrels 0:00:19.360 --> 0:00:24.239 store their food tree fruit like acorns in their nests 0:00:24.360 --> 0:00:28.360 or dens to snack on all winter. Here's the thing 0:00:28.760 --> 0:00:31.680 they actually don't do that. First, it's important to know 0:00:31.760 --> 0:00:34.920 that both the Eastern gray and Eastern fox squirrels dine 0:00:34.960 --> 0:00:40.760 on a varying menu of seeds, nuts, acorns, tree buds, berries, leaves, 0:00:41.000 --> 0:00:43.720 parts of pine cones, and other food some of us 0:00:44.000 --> 0:00:46.200 well we don't like to think about, like bird eggs 0:00:46.200 --> 0:00:49.800 and nestlings, and as well. You know they'll have the 0:00:49.800 --> 0:00:53.080 occasional slice of found pizza. Some of that stuff they 0:00:53.120 --> 0:00:55.800 eat right away, the rest they take to the nest 0:00:56.040 --> 0:00:59.960 or den for later. But when winter approaches, squirrels are 0:01:00.040 --> 0:01:03.520 faced with a challenge. They know instinctively that food sources 0:01:03.520 --> 0:01:06.000 will soon be scarce, so they gather all the food 0:01:06.040 --> 0:01:10.920 they'll need while also keeping themselves fed day today. That's 0:01:11.000 --> 0:01:14.120 why they're so busy in the fall. When Mother nature 0:01:14.200 --> 0:01:17.360 has made sure that all the acorns have fallen from 0:01:17.400 --> 0:01:21.920 the trees. Second, Eastern gray and Eastern fox squirrels are 0:01:22.440 --> 0:01:25.440 scatter hoarders, which means pretty much what it sounds like. 0:01:25.600 --> 0:01:28.720 They hoard their food and then scatter it in locations 0:01:28.760 --> 0:01:32.760 where they can easily access it. That's usually close to 0:01:32.800 --> 0:01:36.120 the tree holding their nest or den, but they often 0:01:36.240 --> 0:01:40.399 expand into areas of seven acres or two point eight 0:01:40.560 --> 0:01:45.040 hectic ers, and rather than leaving their goods above ground 0:01:45.080 --> 0:01:48.400 where other squirrels can steal them, they bury them, and 0:01:48.480 --> 0:01:52.000 this is called cashing about an inch maybe two point 0:01:52.080 --> 0:01:55.920 five centimeters under the soil, and squirrels are known to 0:01:56.160 --> 0:01:59.560 crack open a nut before burying it so they can 0:01:59.640 --> 0:02:02.800 keep it from germinating. When it comes time to eat, 0:02:03.080 --> 0:02:06.320 they forage for the nuts they buried. While squirrels possess 0:02:06.400 --> 0:02:09.040 a strong sense of smell, which allows them to sniff 0:02:09.080 --> 0:02:12.440 out nuts from under a blanket of dirt, researchers have 0:02:12.600 --> 0:02:16.799 long noticed evidence of strategic intelligence in the placement of 0:02:16.960 --> 0:02:20.679 their food. For instance, one study in two thousand eight 0:02:20.680 --> 0:02:25.720 reported that Eastern gray squirrels engage in what's called deceptive cashing. 0:02:26.040 --> 0:02:28.840 They dig a hole pretend to throw the acorn in 0:02:29.360 --> 0:02:31.800 while they hold it in their mouth. Then they cover 0:02:31.880 --> 0:02:35.040 up the empty hole and run off to another secret 0:02:35.080 --> 0:02:38.600 stash place. And they do this it was suggested to 0:02:38.840 --> 0:02:42.120 fool other squirrels who might be watching them. But a 0:02:42.120 --> 0:02:45.600 new study from professors in the Department of Psychology at 0:02:45.600 --> 0:02:49.520 the University of California at Berkeley and published in the 0:02:49.560 --> 0:02:53.240 September issue of the journal Royal Society of Open Science, 0:02:53.600 --> 0:02:58.640 claims that tree squirrels use a pneumonic technique called spatial 0:02:59.080 --> 0:03:04.680 chunking to sort out and bury their nuts scores by size, type, 0:03:04.720 --> 0:03:09.280 and perhaps nutritional value and taste now when they're hungry later, 0:03:09.440 --> 0:03:13.560 it's theorized they can remember where to find what they want. 0:03:13.840 --> 0:03:17.600 In other words, the squirrels put specific nuts in similar 0:03:17.600 --> 0:03:21.359 places to help them remember what nuts were where. I e. 0:03:21.880 --> 0:03:24.919 Almonds were placed in one general area, hazel nuts in another, 0:03:25.000 --> 0:03:27.480 and I guess pizza would go in a third area. 0:03:27.919 --> 0:03:32.200 This neumonic strategy has also been seen in rats. The 0:03:32.280 --> 0:03:35.560 finding researchers right in. The studies show that a scatter 0:03:35.680 --> 0:03:40.440 hoarder could employ spatial chunking during cash distribution as a 0:03:40.520 --> 0:03:46.040 cognitive strategy to decrease memory load and hence increase accuracy 0:03:46.160 --> 0:03:49.440 of retrieval. Squirrels have got a lot to think about. 0:03:49.480 --> 0:03:52.920 In other words, they need all the memory tricks they 0:03:52.960 --> 0:03:55.280 can get, so the next time you see a squirrel 0:03:55.360 --> 0:03:57.920 digging up a nut, know that she might have just 0:03:58.040 --> 0:04:07.160 found the exact one she was hoping for. Today's episode 0:04:07.200 --> 0:04:10.320 was written by Jamie Allen, produced by Tristan McNeil and 0:04:10.360 --> 0:04:13.240 For more on this and other topics, please visit us 0:04:13.320 --> 0:04:26.360 at how stuff works dot com.