I just wanted to add another anecdote (because the plural of anecdote is, as we all know, data) that your profess isn’t the only one. I’ve heard a few similar stories about guys not being allowed to enter the rodent living chambers besides an initial, introductory visit in the past.

This is really interesting. Clearly they're trying to control for sensitive variables that make little sense even to them, and yet they're still using rodents as subjects and publishing studies likely without mention of these oddities. Not saying everyone is doing it wrong, but wow.

You have to allow for some level of pragmatism. They found a method that seems to provide better data without actively biasing their results. Rodents make convenient test subjects, and no scientist wants (or more likely it doesn't even occur to them) to include an unproven methodology in their published work.

Are they publishing "make sure only [female name] handles the mice"?

Or do they just publish, "X caused effect Y"?

Frankly, identifying why it requires a female, or female non-cat owner sounds like it may be more interesting than whatever other result they are working on...

If results were thrown out because of a confounding factor then it would hopefully be mentioned in the paper.

I've had a similar thought about these little insights. There are literally thousands of times more biology undergrads than there are people doing biology research. Biological experiments are notoriously difficult to conduct. There are so many confounding variables, data is hard to collect, etc, that experiments bomb as often as they succeed.

A lot of these experiments are extremely well supported, so you might actually be able to discover something novel if you were able to track the failures.

Anyways, I don't do anything with biology anymore, but I strongly believe that biology is a field where citizen scientists could make a meaningful impact.

Another thing to consider is epigenetics.

https://www.newscientist.com/article/dn24677-fear-of-a-smell...

I wonder how practical it would be to automate all the rodent handling/experimenting? Because that seems like it'd be the only way to properly remove such unaccountable influences, like people smelling of cat/giving off different smells and thus influencing the reactions of the animals.

Couldn't it also be possible that rodents reacting like that is the result of established practices? I.e.: Rodents get only handled by females, rodents adapt to that female smell while reacting differently to the male smell due to its unfamiliarity?

Then you would have to deal with the effect of subjecting the mice to such a degree of control, precision of action, predictability of environment, and other factors. As was found with the 'Rat Park' experiments in the 70s, experiments on rats in cages are not informative about the behavior of rats not in cages. It is tremendously difficult to study systems as complex as living animals, and we ignore "unimportant" factors at our peril. How different would our society be if the Rat Park experiments, which showed that rats addicted to cocaine will naturally ween themselves off of the drug when provided with a stimulating social environment, was reported on first instead of the one we heard about instead that claimed cocaine was so addictive that a rat which takes a dose becomes inescapably addicted and will dose themselves with it until they die? (Which they will.... if they are locked in a cage and the alternative is just living in a miserable cage.)

Rat Park can only sometimes be replicated:

https://www.ncbi.nlm.nih.gov/pubmed/9148292?dopt=Abstract

https://www.ncbi.nlm.nih.gov/pubmed/2616610

https://www.ncbi.nlm.nih.gov/pubmed/3696469

https://www.ncbi.nlm.nih.gov/pubmed/18463628

SSC wrote an article about it:

http://slatestarcodex.com/2017/10/25/against-rat-park/

Even automation would not solve this issue. If these results are scent related, then it is quite possible that different automation methods would produce different scents, or even the same method, in a different environment / location.

This is a fascinating issue.

But you could at least use the same automation methods across different study groups within the same study, eliminating potential confounding variables between your groups.

Were rats as sensitive as mice?

Fwiw I have been assured that Big Pharma will swap out a set of mice (or whatever the test species is) as a way to find the results they're looking for. This was told to me by someone who does research for Big Pharma. Someone who I have no reason not to trust.

But how can we trust you to tell the truth about this?

My personal motto is:

Don't be evil.

Does that help? ;)

Google has the same motto, and we can see how that's going...

It’s Alphabet now, they don’t have that motto ;)

interesting stuff, hope this was all documented in the papers derived from those experiments

I didn't go to a research University, and I'm fairly sure none of the staff used mice as a model organism. I think they were merely used in student experiments.

Now some of those students may have published work as part of their senior capstone, however it's pretty unlikely. You need a lot of knowledge to get to the point where you can publish something meaningful in biology. If you were to publish a work as an undergrad, you are probably working on a professor's project or with a less complicated topic.