Rats! For a lot of people that very word sends a shiver down their spine and brings up images of terrifying, shifty-eyed little pests that spread disease. Movies like Lady and the Tramp, The Princess Bride, and The Great Mouse Detective instill this perception from a young age with their antagonistic rat characters. Although media is starting to recognize the kinder, cuter side of rats with movies like Ratatouille, ask most New Yorkers how they feel about rats and they’ll probably respond with a look of disgust. When most people think of rats, they think of the little critters scuttling across dirty subway tracks or stealing slices of pizza. However, these little rodents aren’t actually so dirty and evil when you get to know them! Rats actually make excellent pets, because these little beings are incredibly social, intelligent, and friendly! While I’m sure any rat owner can tell you this, we have science to prove it too! (Pictured below is the nasty rat from Lady and the Tramp, 1955)
First of all, rats are friendly! The first study highlighting a rat’s sociable qualities is a 2011 study by first author Dr. Bartal. Here, rats were given the opportunity to free a cagemate from a small box, called a restrainer. The authors found that once the free rats learned how to open the restrainer, a vast majority of them would open it and free their cagemate quickly and intentionally. Even when the rats didn’t get to come into contact after, they still freed their cagemate. To test this kindness a little further, the scientists added another restrainer with chocolate instead for the rats to choose between. Even with such a delicious treat available, the freed rats opened the restrainer just as quickly as before, showing that the chocolate didn’t slow them down from freeing their friend! In fact, free rats often ate less chocolate when the cagemate was present than when they were alone, indicating they even saved some for their friend. This study shows rats will help out another rat in need and a lot of times even share treats. If you’d like to learn more about this study you can check out the following youtube video!
Rats are also playful, and they enjoy spending time with their human companion too. At least, that’s what another study by authors LaFollette et al. found in their 2017 review of tickling rats. Yes, tickling! It turns out rats love being tickled and they really love when their human tickles them. When rats are tickled they even make very high pitched vocalizations, too high pitched for us to hear, but rats only make them when they’re feeling positive so it’s similar to human laughter in that way! That rats enjoy this contact at all shows that rats enjoy the companionship of humans. (Photo below of tickled rat by Megan R. LaFollette.)
The final study I would like to share in favor of the rats is a new study by Dr. Crawford et al. put out just this year. In this study, these scientists at the University of Richmond trained rats to carry out an impressive and complex task; they taught rats to drive a tiny car! The rats seemed to enjoy learning this complex task too, given the fact that not only did they voluntarily participate in the training (no rat was ever forced to practice!), but after driving the little car around, the researchers found that the rats’ metabolized stress hormones more efficiently after learning to drive. Essentially, this means that the rats were more emotionally resilient and, therefore, healthier and happier, afterwards! So not only are rats smart enough to learn such a tricky task, but they seem to enjoy it too. (Photo below of rat in vehicle by Kelly Lambert with the University of Richmond)
So overall, we’ve learned quite a bit about what rats can do! They’ve shown us that they are social because they are concerned about other rats and they enjoy playing with us, their human companions. They’ve shown us they’re intelligent because they can figure out tricky skills like how to open boxes and how to drive their tiny little rat-made vehicles. There are plenty of humans who can’t even drive a car! So now I’d like to turn your attention to a final part of their stereotype; the assumption that all rats are mangy little grey rodents. Again, this is not so! As a parting gift, here is a lovely graphic of some of the many interesting varieties rats can come in, courtesy of artist Rebecca Karlén.
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Bartal, I. B. A., Decety, J., & Mason, P. (2011). Empathy and pro-social behavior in rats. Science, 334(6061), 1427-1430.
Crawford, L. E., Knouse, L. E., Kent, M., Vavra, D., Harding, O., LeServe, D., … & Lambert, K. G. (2019). Enriched environment exposure accelerates rodent driving skills. Behavioural Brain Research, 112309.
LaFollette, M. R., O’Haire, M. E., Cloutier, S., Blankenberger, W. B., & Gaskill, B. N. (2017). Rat tickling: A systematic review of applications, outcomes, and moderators. PloS one, 12(4), e0175320.