Published
By Helen Briggs
BBC News
Its stripy back makes it one of the most recognisable of rodents - but until now it has been unclear exactly how the chipmunk earned its stripes.
Now, scientists have found the evolutionary gene change responsible for the distinctive markings of both the chipmunk and an African mouse.
The gene normally makes the bellies of many rodents light in colour.
The stripes may have helped the animals hide from daytime predators with keen eye sight, such as birds, they say.
Prof Hopi Hoekstra, of Harvard University, US, who led the research, said: "What these two rodents have in common is that they are both diurnal [active during daylight], when one could imagine stripes could be more valuable than if they were nocturnal.
"It is notable that of the rodents that are striped, most are diurnal - again consistent with them being important for evading visual predators (for example, raptors and mammalian carnivores)."
Mystery patterns
The African striped mouse has a pattern of two dark-light-dark stripes on its back.
The dark and light stripes can be seen as soon as the mouse pups are born.
Research shows a gene change causes skin cells called melanocytes to stop making dark pigment in a particular area of the mouse's back, causing a white stripe.
A similar thing happens in the chipmunk.
Image source, J. F. Broekhuis
Image source, Elaine Kruer
In some other animals, white patches are caused by a lack of melanocytes in a particular area of the body - such as the blaze on the nose of a horse or a white bib on a cat.
"Overall, we know very little about how pigment patterns form, especially in mammals," said Prof Hoekstra, an evolutionary biologist at Harvard University.
Evolution must have "tinkered" with the gene that normally makes the bellies of many rodents light in colour, she said.
"In other words, a gene working to make bellies light in colour was co-opted and reused in both chipmunks and mice to also make light-coloured stripes," Prof Hoekstra said.
Chipmunks are part of the squirrel family, and split off from mice and rats about 70 million years ago.
Scientists think they probably evolved their stripes independently.
The research is published in the journal Nature.
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FAQs
Is How Chipmunk Got His Stripes a fable? ›
We are going to read The Lion and the Mouse,which is an Aesop Fable and How Chipmunk Got His Stripes,which is an Indigenous folktale.
What type of story is how chipmunk got his stripes? ›What happens when a little brown squirrel teases a big black bear? Brown Squirrel gets stripes and is called chipmunk from that day forward . . . Joseph and James Bruchac join forces to create this buoyant picture book, based on a Native American folktale. Illustrated by Jose Aruego and Ariane Dewey.
Why is Bear unhappy when the sun comes up? ›Why is Bear unhappy when the sun comes up? He doesn't like being teased. He doesn't like being wrong.
Why do chipmunks have black stripes? ›What the researchers found was that a gene that normally causes pale belly fur has been co-opted to help create a pattern of light and dark stripes on the backs of both striped mice and on the distantly-related chipmunks. The mice generally have tan fur.
How Chipmunk Got His Stripes illustrator? ›Brown Squirrel gets stripes and is called chipmunk from that day forward . . . Joseph and James Bruchac join forces to create this buoyant picture book, based on a Native American folktale. Illustrated by Jose Aruego and Ariane Dewey.
What is the moral of Alvin and the Chipmunks? ›The main messages from this movie are that material wealth doesn't bring happiness and that family, commitment and caring for those you love are important. You could talk to your children about these values as well as about the effects of fame.
What are Alvin and the Chipmunks backstory? ›Named for three record executives from the Chipmunks' original label, Alvin, Theodore, and Simon became fan favorites. They were animated in 1961 for a short-lived television series and released a number of albums until the death of Bagdasarian Sr.
How many stripes does a chipmunk have? ›However, there are some key ways to tell these creatures apart. The eastern chipmunk (Tamias striatus) has seven stripes on its body --- a single black stripe running down the middle of its back and three stripes on each side going black, white, black. The stripes do not extend onto the head.
Why is it called chipmunk? ›The name "chipmunk," said to be of native American origin, apparently derives from the chipping call these mammals make. The genus name (Tamias) is from the Latin word meaning "collector" or "storer" – a reference to the Eastern Chipmunk's winter survival strategy of storing food in its burrow.
How the squirrel got its stripes? ›When one of the monkeys picked the squirrel up by the tail and threw him away, he fell into Lord Rama's hands. 5. When the squirrel fell into Lord Rama's hand, he gently and lovingly ran his fingers on the squirrel's back. The stripes on the squirrel's back are the marks of Lord Rama's fingers.
Is chipmunk a female? ›
Look at the genital area, which is located above the anus. In the genital area, males will have two bumps that are about one centimeter apart from each other. In females, the bumps are touching each other.
Why do Siberian chipmunks have stripes? ›After its stripy back, it is usually the large dark eyes that a new observer notices first. The striped coat of the Siberian Chipmunk is distinctive when the animal is in the open, but provides suitable camouflage when amongst vegetation or dappled light.
Do chipmunks have to have stripes? ›Chipmunks are small mammals with distinct stripes, while the tree squirrel is larger and doesn't have stripes. The ground squirrel has body stripes like chipmunks, but no head stripes. A tree squirrel is larger, has a longer tail and no stripes. They all have short fur and small rounded ears.
What did the original chipmunks look like? ›The Chipmunks' very first physical appearance were as wooden-headed, soft-bodied puppets on The Ed Sullivan Show in 1958. Their facial structure closely resembled the structure of a real chipmunk's, though their tails were a little larger and bushier.