Ask any child to pretend to be a wolf, and in addition to scampering around on all fours and growling, the child is likely to throw back his or her head and let out a mighty howl. But   why   do wolves howl? Scientists learned a little more about that recently, and the results were released last week in   Current Biology .

As it turns out, part of the reason that wolves howl is for a particularly kid-friendly reason: they miss their friends! Scientists at the Wolf Science Center in Austria discovered that when they took individual wolves out on walks on a leash, the wolves left behind tended to howl. The scientists decided to try to find out why, and they discovered that the closer social relationship a particular wolf had to the wolf being taken on the walk, the more likely the wolf left behind was to howl. Likewise, if the wolf being taken for a walk was higher up in the pack—more popular—the likelier the left behind wolves were to howl.

The scientists wanted to know if the wolves left behind were feeling stressed by the departure of the wolf they were howling for, so they measured their levels of cortisol (the "stress hormone"). They found that cortisol levels were not elevated, so the wolves were probably howling more to communicate with the wolf that left and/or to express sadness or loneliness, than they were to be feeling stressed out or fearful due to the wolf's departure.

You can incorporate this fun fact into your next lesson that mentions wolves, perhaps if you do a unit on   Little Red Riding Hood   and use the   Real World   book   Wolves in the Wild . It would also be a great opportunity to explain to your students that the nature of scientific knowledge is that it is always changing and being refined. When   Wolves in the Wild   was published, we didn't know that wolves missed their friends, and now we do!

If you're interested in reading the original article, the PDF is available   here . To learn more about the   Story World Real World   series that offers a retelling of   Little Red Riding Hood , along with three related informational texts, including   Wolves in the Wild , click the book cover below to visit the web page, or click the information sheet to download it and learn about key features of the series. Happy howling!

Photo credit: Stayer