Scientists Discover That Shrews Shrink Their Heads in Winter

Kamie Berry | October 25th, 2017

Nature is full of amazing animal adaptations. There are lizards who change color to blend in with their surroundings. There are multiple animals who can sleep through an entire winter without eating anything. And there are even fish that come equipped with built-in flashlights. And now, scientists with the Max Planck Institute for Ornithology in Germany have discovered a new adaptation which is just as interesting as those already mentioned.

The common shrew, which is a tiny insect-eating mammal that lives in parts of Europe and Asia, actually shrinks its skull and body as winter approaches. Then, when spring starts to arrive, it regrows itself.

shrewsunited.weebly.com

This phenomenon has long been suspected, but this is the first study to finally prove that the phenomenon occurs. After catching, measuring, and taking X-rays of a number of wild shrews, researchers on this study found that, on average, shrews shrink their braincases by 15% when the weather gets colder. Some shrews’ brain size shrunk by up to 30%. Body mass also decreased significantly.

When spring arrives, the shrews regrow their braincases by an average of 9%, which means they don’t return to their original size. Since shrews only live a little longer than a year, they only go through this process once, and they never re-attain their previous size.

But what purpose does this shrinking serve?

Shrews don’t hibernate or migrate, so they must do something to deal with the decrease in their food supply in the colder months. Winter is a period of extreme food scarcity for these little animals, and the reduction in body mass reduces calorie requirements in them. They have high metabolisms and must constantly eat to maintain their weight. By reducing this weight, they don’t have to eat as much when there is little food available.

The brain is one of the body’s most energy-expensive organs, meaning it takes a lot of calories to keep it running. So, by reducing their brain size, the shrews are again reducing their need for food during the harsh winter months.

Now scientists know that the shrinking process definitely occurs, but they still aren’t sure how it happens. One theory is that the collagen that makes up the cranial sutures is reabsorbed by the body. More research will need to be done to figure out this remaining mystery.

Next Article
  • From Poverty To Becoming A Millionaire Oil Baron

    Sarah Rector was born in 1902 in Oklahoma on Muscogee Creek Indian allotted land to two parents who both came from enslaved ancestry. In 1907 when Oklahoma passed a law that ordered the Creeks land to be divided between the Creeks and also their former slaves. This meant that Sarah Rector and all her family...

    Read More
  • A North American Casino Was Hacked Via A Smart Fish Tank

    When it comes to browsing the internet most people are now aware of phishing scams where hackers try to fake popular websites and get you to give them your personal details. One casino in North American found out about an entirely different type of hack, one that had to do with actual fish. One of...

    Read More
  • In 1962 Maryland Declared Jousting Their Official State Sport

    One would have thought that jousting was reserved for a bygone time, the medieval ages. A time of knights, kings, and princesses; all galloping furiously on their noble steeds. Tipped from head to toy in ancient armor, jousting was a sport that was much loved for decades. Of course, as we entered the modern times...

    Read More
  • There Has Only Ever Been One Submarine VS Submarine Fight Ever!

    A famous film that dramatized underwater battle for the whole world to see is, of course, The Hunt For Red October, it portrayed a nerve-racking experience with crews deep under the ocean searching for their enemy with sonar. And though it is true that hunting undersea enemies is, of course,...

    Read More
  • Nuclear Pasta The Strongest Material In The Universe

    If you happen to be in the industry of creating the strongest materials in the universe, then you are in luck. We have the recipe and it only takes three easy steps: Find yourself one dying star and put into your favorite boiling pot, boil it until it goes supernova and explodes. Beware this could...

    Read More
  • Sometimes Little Galaxies Are Actually Cannibals

    Astronomers around the globe have long seen big galaxies like the Milkyway swallow up some of their little brothers and sisters. In fact, the sky is full of cannibals. They swallow up stars that are in their cosmic neighbors, and over time eat up whole galaxies. It seems only natural, that even in space, the...

    Read More
  • A 20 Min Extra Commute Is Worse On The Mind Than A Pay Cut

    A new study into what is seen as most negative when it comes to our daily work routines shows that being told you will need to commute an extra 20 mins to get home is just as bad as being informed about a pay cut. When it comes to job satisfaction it seems that commuting...

    Read More