Mice are the most commonly used animal in research, and it’s by a country mile. 

In Great Britain, mice accounted for 70.9% of all regulated procedures using animals in 2024. To help you understand the scale, that’s 1,869,064 experiments using mice. 

Mice, and rodents in general, have become synonymous with medical research. We have phrases like “lab mouse”, “lab rat” and “guinea pig” to mean “tester”, and mouse iconography is everywhere when it comes to research. (Imagine me at this point, gesturing vaguely towards our logo and its lovely mouse icon) 

But why mice? After all…

• They’re very small compared to humans. 

• They have much shorter life spans. 

• They procreate much quicker than us. 

• We don’t even hear things on the same frequency. 

So have they become the de-facto ‘model’ for researching human health? The Victorians. It’s always the Victorians.

The National Mouse Club

Let’s go back to 1895, remember those days? Me neither.  

Anyway, “lab mice” weren’t really a thing at this point. But “mice fanciers” absolutely were. A group of British enthusiasts founded the National Mouse Club (which exists to this day by the way!).  

The mouse club members bred mice as pets with a focus on aesthetic traits like coat colour, unique patterns, or specific temperaments and behaviours. This is not so uncommon when you think about ‘designer’ cats and dogs, like pugs or Bengal cats. There would be competitions for the top mouse, so their focus wasn’t on research but shiny, shiny trophies.  

Because these hobbyists were very competitive, they would keep meticulous records of mice lineage. These Victorian pet breeders created one of, if not the, first documented mammalian genetic databases. This, again, isn’t dissimilar to modern registries for pedigree dogs. 

But how do we go from trophies to labs? Scientists were looking for large numbers of genetically similar animals to test their theories. Luckily, for them at least, they knew just the place and went to the local hobbyists who already had the best record-keeping and the biggest cages.

Enter the Mouse Woman of Granby

Now we have to head over the Atlantic. In 1900, a retired schoolteacher named Abbie Lathrop started a “fancy mouse” farm in Massachusetts to make ends meet, selling the animals to children as pets. 

When Lathrop noticed some of her pet mice developing skin tumours, she reached out to university researchers and started collaborating with them. 

She ended up co-authoring scientific papers and supplied thousands of mice to Harvard and the American government.  

One specific mouse in her barn was designated Mouse Number 57. That single pet mouse became the ancestor of the C57BL/6 (often called the “Black 6”), which remains the most widely used lab mouse strain in the world today. 

Where does that leave us today?

This is where the history lesson intersects with the work we do today. 

We’re often told that animal research is an unavoidable part of science. But history shows us a different story. We didn’t choose mice because they were the perfect biological mirror for human beings. We chose them because they were cheap, available, easy to house, and already domesticated by Victorian pet breeders. 

It was a choice of convenience that quickly hardened into a habit. There are lots of names for this, like “path dependency”. It basically means it becomes easier to keep using an old tool because everyone else is using it and you can easily compare results. 

Upgrading the Tools

Using animals isn’t an inevitable, permanent law of science, very little is. 

It is an important chapter of scientific history, and we’ll never deny that medical advancements have happened as a result of animal research. What we will deny is that that’s reason to continue with animal research. 

History moves forward, and so must we. Now we have 21st-century tools like organ-on-a-chip technology and advanced computer modelling that are designed to mimic human biology, it’s better for all animals, humans and non-human.