3 ms·

Mice are small. Their surface / volume ratio is MUCH higher. They lose heat a lot faster than we do.

saalweachter 13y ago
All other things being equal, yeah. But while a six foot tall mouse would lose heat way slower than a normal sized mouse, people and mice have different amounts of fat and fur. It's not obvious to me a priori that mice would have a different optimum temperature range. I mean, England barely ever has a high of 31C, and there are plenty of mice there. I wouldn't suspect that every mouse in England is immunocompromised.
- ljf 13y ago
  Other points - mice rarely have bedding in their cages which they use to increase their body heat, and also to sleep in, which allows them to lower their temperature without ill affect (why many animals sleep through the night. Nests in cages mean mice can't be observed, so are usually not provided. Mice are kept lean, so have limited body fat for warmth. Mice are kept in overly-well ventilated cages, which adds to the cold felt. Many mice are bred for limited or low fur, which again means they need a higher mean temperature to stay warm. Lastly the cages encourage non wild behaviour, and are rarely enriched with toys, or have long spaces in which to run, which the animals also use to mediate their body temperature.
  - gohrt 13y ago
    Basically, doing "normal" biology/psychology experiments "lab" mice is sort of like doing those experiments on astronauts living on the moon. A rather horrid mis-approximation of the experience/behavior of normal population. The moden scientific laboratory design puts so much emphasis on precision (cages, diets, etc, for consistent experimental outcomes), that it fails miserably at accuracy (similarity to what non-experimental individuals)
    - saalweachter 13y ago
      We've always known that lab animals are not perfect models of human biology. For instance, human livers -- for our body weight -- are several times larger than mouse livers. This has important consequences on how we deal with toxins. Mice have been valuable tools not because of how good a model they are but because they're cheap and fast. Apes are a much better animal model for most purposes, but they're expensive and slow, and raise way more moral questions. And people as test subjects are all that and a bag of chips. Instead, researchers using animals work to understand how an animal model compares to humans. They pick their animal test subjects based on what they're researching; for instance, rabbits might be better for researching a particular disease, and cats might be better for researching a particular cognitive disorder. So -- assuming this new information holds up to replication -- what this means is that we potentially have a more accurate, cheaper animal model on hand than we previously thought. If mice at 31C behave significantly differently than mice at 25C, then researchers will be able to use mice in cases they previously weren't, eliminating the need for other animal models or even some human testing in some cases (eg, the experiments will fail at mice and never make it to human testing). This will save money, and speed up research.

All other things being equal, yeah. But while a six foot tall mouse would lose heat way slower than a normal sized mouse, people and mice have different amounts of fat and fur. It's not obvious to me a priori that mice would have a different optimum temperature range. I mean, England barely ever has a high of 31C, and there are plenty of mice there. I wouldn't suspect that every mouse in England is immunocompromised.

ljf 13y ago
Other points - mice rarely have bedding in their cages which they use to increase their body heat, and also to sleep in, which allows them to lower their temperature without ill affect (why many animals sleep through the night. Nests in cages mean mice can't be observed, so are usually not provided. Mice are kept lean, so have limited body fat for warmth. Mice are kept in overly-well ventilated cages, which adds to the cold felt. Many mice are bred for limited or low fur, which again means they need a higher mean temperature to stay warm. Lastly the cages encourage non wild behaviour, and are rarely enriched with toys, or have long spaces in which to run, which the animals also use to mediate their body temperature.
- gohrt 13y ago
  Basically, doing "normal" biology/psychology experiments "lab" mice is sort of like doing those experiments on astronauts living on the moon. A rather horrid mis-approximation of the experience/behavior of normal population. The moden scientific laboratory design puts so much emphasis on precision (cages, diets, etc, for consistent experimental outcomes), that it fails miserably at accuracy (similarity to what non-experimental individuals)
  - saalweachter 13y ago
    We've always known that lab animals are not perfect models of human biology. For instance, human livers -- for our body weight -- are several times larger than mouse livers. This has important consequences on how we deal with toxins. Mice have been valuable tools not because of how good a model they are but because they're cheap and fast. Apes are a much better animal model for most purposes, but they're expensive and slow, and raise way more moral questions. And people as test subjects are all that and a bag of chips. Instead, researchers using animals work to understand how an animal model compares to humans. They pick their animal test subjects based on what they're researching; for instance, rabbits might be better for researching a particular disease, and cats might be better for researching a particular cognitive disorder. So -- assuming this new information holds up to replication -- what this means is that we potentially have a more accurate, cheaper animal model on hand than we previously thought. If mice at 31C behave significantly differently than mice at 25C, then researchers will be able to use mice in cases they previously weren't, eliminating the need for other animal models or even some human testing in some cases (eg, the experiments will fail at mice and never make it to human testing). This will save money, and speed up research.