Residing with Lab Mice

Bullie was essentially the most caring individual within the group. Each time another person was ailing, she would sit along with her and luxury her. Bram and Wezel had the strongest friendship. There was simply the 2 of them after their mates had died, they usually did the whole lot collectively: consuming, sleeping, pottering about like an previous married couple. In addition they took up nest-building and created stunning flower-shaped nests for sleeping in.

Bullie, Bram, and Wezel have been three of the 25 ex-laboratory mice with whom I lived between 2020 and 2023. These mice have been a part of a pilot mission for the adoption of small laboratory animals—mice and rats—arrange by a coalition of Dutch animal advocacy organizations and Utrecht College, within the Netherlands. 

I’m a thinker who writes in regards to the languages and political company of nonhuman animals. Once I adopted these mice, I regarded ahead to interacting with them and maybe changing into mates. The mice quickly made clear that they weren’t enthusiastic about that. Each time I put my hand of their home, they checked out it with disgust and tried to bury it. I made a decision to play music for them, as a result of they did like my voice. Once I performed songs for them on the guitar and ukulele, I watched them. Via spending time with them, I realized that mice should not the type of beings that almost all people assume they’re.

Mice are utilized in experiments as a result of they’re small and low-cost, as a result of they make a number of infants rapidly, and since people see them as simplistic, mechanistic, and replaceable. Within the Netherlands, the place I’m primarily based, round 200,000 mice are utilized in experiments yearly, and about as many are bred however not used. Almost all are killed. In the US, an estimated 10 to 111 million mice are used every year; rodents should not lined by the federal Animal Welfare Act, so actual counts should not made. But though people use so many mice, we all know surprisingly little about them.

It’s because the experiments are targeted on people. Laboratory mice are not often studied to study mouse cognition, feelings, or social life for their very own sake. As an alternative they’re used to create information about human our bodies, minds, and illness. Other than the numerous issues of extrapolating from mice to people, these findings don’t all the time give us a transparent image of mice. For instance, mice are steadily petrified of male scientists, which can confound observations. The situations underneath which mice reside additionally distort insights. Other than their captivity and tedium, they’re typically chilly.

To be able to perceive these mice who got here to reside with me higher, I regarded for research in regards to the social lives of laboratory mice: about their characters, friendships, communities, the methods wherein they play. I didn’t discover any. There are many research on capacities like “emotional contagion,” or behaviors like “affiliative grooming”—however these research paint an incomplete image as a result of they solely concentrate on one facet of mouse life, and got down to map species traits as a substitute of people and social relations. In fact, lab mice usually don’t reside lengthy sufficient to construct a neighborhood, and scientists normally view them as objects of a examine as a substitute of topics with a life that issues most to them. 

I realized that mice should not the type of beings that almost all people assume they’re.

I then regarded for research in regards to the social lives of mice extra usually. Once more I didn’t discover what I used to be searching for. There are research about mouse communication, intercourse lives, and social construction, however no long-term research of their communities as there are for, say, chimpanzees or corvids. I made a decision to jot down about mice myself.

I’m not a biologist or ethologist, and as a thinker I’m fairly crucial of human-centered methods of attending to know different animals. I turned to the work of ethologists like Barbara Smuts, who lived with a troop of baboons, and Len Howard, who opened her English countryside residence to the birds dwelling outdoors as a result of she wished to get to know them. They realized to see different animals by attending to them over lengthy durations of time and on their very own phrases, approaching them as beings who had their very own views on life. I made a decision I might attempt to do the identical with laboratory mice.

In order to search out out extra in regards to the relationships between the mice and to know their practices I first wanted to study who was who. The primary group I adopted consisted of 10 feminine mice. Every had brown hair. After just a few days I started to acknowledge the variations between them. I made an inventory of their names and bodily traits. Some have been larger, like Grote Muis (Huge Mouse) and Kleinoor (Small Ear). Different mice have been smaller, like Kleine Muis (Little Mouse) and Kraaloog (Beady Eye). Witoog (White Eye) had a white ring round one in every of her eyes, and thru describing them on this approach I realized to see who was who. After some time I additionally started to see variations of their characters. Flankie was all the time the primary to check out new meals and homes. Vachtje was a little bit of a loner. Kleinoor and Grote Muis have been calm, Kraaloog was feisty and quick.

Slowly I started to know their types of expression. They made a chk-chk sound after they explored, which expressed a type of content material curiosity. They squeaked loudly whereas being groomed. Once they wished to be groomed, they’d a particular motion—holding half of their face flat to the ground—that they used as invitation. Holding their tails straight up meant pleasure. Mice who appreciated one another typically sat with the ideas of their tails wrapped collectively. The mice additionally had many greetings, like kissing each other on the mouth, intertwining their tails’ ideas, and aligning their posture with that of one other.

Over time I additionally started to see how significant a few of their habits and practices have been. The primary time I clearly noticed this was when Vachtje couldn’t run within the train wheel anymore due to her tumor. (Most of the mice developed tumors, and never a lot well being care was out there for them. That is ironic, given how a lot we find out about their our bodies and the way a lot most cancers drug analysis includes mice.) The mice appreciated working within the wheel; when another person was already working, they sat subsequent to the wheel and gauged its velocity with their palms earlier than leaping in. When Vachtje couldn’t make the bounce anymore, she nonetheless sat beside the wheel and moved it along with her palms.

The mice additionally modified over time. A easy instance is grooming. Within the first days after a brand new group arrived, I solely noticed them groom themselves, however by no means each other. They normally started mutual grooming after per week or so—fairly lengthy in mouse time—within the shoeboxes wherein they slept. As time went on, they turned extra snug grooming out within the open, they usually particularly appreciated to make use of the roof of the sleeping shoebox for this.

Once they obtained older, they additional developed their practices of care. The primary 12 months with every group was best: all mice have been wholesome and comfortable. However after a few 12 months, they started to develop diseases—principally tumors, however additionally they had strokes. Each time a mouse was ailing, others took care of her. They might sit subsequent to her to assist her with their physique whereas consuming; wholesome mice slept subsequent to mice who have been unwell, maybe to maintain them heat. I twice witnessed the mice kind a circle round a mouse who was ailing. A scientist would possibly write about this as their buying probably helpful details about their setting. To me it regarded like a circle of care.

Vachtje was a little bit of a loner. Kleinoor and Grote Muis have been calm, Kraaloog was feisty and quick.

In addition they started caring for their lifeless companions. Each time a mouse died, I left her physique within the mouse home, in order that the others may perceive she was lifeless and say goodbye. I noticed the identical response in all three teams. With the primary lifeless mouse, they ignored the physique and went on with their enterprise. When the second and third of their companions died, it frightened them. They have been shy and stayed of their sleeping homes greater than common. With the fourth demise, they started caring for the physique. They first greeted the lifeless mouse; then groomed her in the identical approach they groomed their dwelling companions; after which dragged the physique to a nook, the place they buried the mouse with nesting materials and hay. One New 12 months’s Eve I missed Wolkje (Little Cloud) and needed to take all of the containers and wheels out of their home earlier than I discovered her physique, utterly sealed in with items of paper in one of many small play homes.

In fact, I didn’t simply have a look at the mice. In addition they regarded again and tried to determine what sort of being I used to be. Over time we shaped habits, just like the music ritual, and I shared my meals with them. Once they have been previous, they might roam freely within the room the place their home was situated and weren’t petrified of me, so our contact grew. However they have been nonetheless principally enthusiastic about each other and I didn’t kind robust relationships with them. This modified with Spokie.

Spokie was the final mouse of the final group. After her mates died, she was too previous to match to new mice. She had by no means been very social and I used to be glad that it was her who remained, and never somebody who was extra connected to the opposite mice and would miss them. Nonetheless, I frightened she felt alone, and I typically sang or spoke to her. She’d then come out of her home to greet me. We additionally went on journeys via my home: I introduced her to completely different rooms and she or he loved exploring new areas. She was not quick anymore, and this was in summer season, so we additionally went into the backyard, the place she may roam via the grass whereas I sat subsequent to her. At first she appeared detached to my presence, however as time handed she stayed shut and sat with me. Someday she invited me to groom her. She held one facet of her face all the way down to the ground and checked out me with the opposite eye. I acknowledged this posture from when the mice invited different mice to groom them. So I started to stroke her head and ears, very softly, as a result of that was what she wished.

In one in every of her books about dwelling with songbirds, Len Howard writes that she can’t make common statements about what sort of animal an excellent tit is. All of them have their very own personalities, much like people. Howard doesn’t imply that birds do not need widespread traits; moderately, she desires to attract consideration to the truth that they’re people, and that defining them in species-general methods dangers obscuring their individuality. 

The identical will be mentioned of mice. Flankie, Bullie, Spokie, and the others all had their very own characters and personalities. On the similar time, it’s clear that the present picture of mice in human societies and science, as easy, mechanistic, replaceable beings, is solely flawed—so I do wish to make common statements to counter this. The mice who lived with me have been deeply social beings, and care was central to their lives. They continued studying all through life, and saved creating their tasks and relationships with others. 

All animals, I believe, know kind of the identical about what issues in life: neighborhood, love, care, demise. Seeing how the mice lived their lives—not as a biologist or neuroscientist, however as a thinker and fellow creature to the mice—taught me about life itself. As a result of their lives are so quick, I additionally witnessed the cycle of life 25 instances. First you might be younger and search for your home in life; then you might be robust and work in your tasks; you then decelerate; and eventually you grow to be a part of all there’s earlier than you have been born. The mice confirmed me how life and demise are all the time entwined, and the way skinny the thread is that separates them. In the long run, we’re all susceptible beings who’re right here solely briefly. The most effective factor we will do is take excellent care of each other.

• Eva Meijer

  Posted on April 16, 2025

  Eva Meijer is a thinker working on the College of Amsterdam, a author, and a visible artist. Their books embody Multispecies Dialogues: Doing Philosophy with Animals, Kids, the Sea and Others and Animal Languages. Meijer can also be a member of the Multispecies Collective.

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