Monthly Archives: August 2012

Magnetic Insect Testing

Not sure if people have been doing this for dozens of years in the insect world already (maybe this is common practice?), but I just ran some successful tests on an idea I had that I think could lead to some fun experiments.

I was reading the fantastic book, The Ants, and they were discussing how one of the interesting characteristics of working with superorganisms is that you can non-destructively turn them into mutants. Regular organisms tend to permanently change when you drastically alter them. You cannot do a quick test with an ape to see how it behaves differently if you remove its liver, or chop off its arm, and then return it to normal the next day. Regular organisms are quite fragile in this way.

As Holldobler and Wilson point out, though, Superorganisms are quite flexible. Interesting experiments can be done where various parts of the being are removed, like temporarily taking out all the ants in the soldier caste, and the hive can be returned to its original state at the end of the day.

I was trying to think of ways in which you could speed up this process and have a constantly, rapidly mutating colony.  How might one be able to quickly remove a select target group of individuals from a nest (without sitting there hunting with tweezers).

Then I thought of magnets!

Magnetic paint already exists, but apparently only in aerosol or latex paint, not good insect friendly paint like enamel paint. So i tried out making my own. First I had some success with mixing iron filings with enamel paint.

My first test subject, a palmetto bug, was sucessfully recaptured after her daring escape using her newfound magnetic properties.

But these filings were so large that they would rip through the paint and snap out over time. Then I found some (secretly) magnetic powder (that also has the benefit of being flourescent!), and I mixed it with the enamel. This gave me a nice smooth, very attractive paint which worked on large or very small surfaces!

Magnetic Powder Paint subject with many test-swatches.

The key ingredients, magnetic (fluorescent) fingerprinting powder, and enamel paint.


I was thinking you could make a certain target group magnetic, and use a switchable, on-off magnet to collect them and put them back in the nest. But then I was thinking of other fun things you could do with them!

For instance, if all your temnos were painted magnetic, you could use a tiny magnetic rod to more gingerly pick a single one out of a nest instead of worrying about hurting it with tweezers. Also we were thinking it might make them more capacitive, and their movements could be picked up by stuff like ipad multi-touch surfaces (not tested yet). Field scientists that need to recollect the same, marked bugs, can also use this to wave powerful magnets around in the bushes for recapture. The coolest idea, though is that you can somewhat manipulate their behaviors at will!

Determining if wet paint has become magnetic (pretty good, needs a bit more powder

Hand-painting small spot on live ant


Here’s a video I made doing a very informal test about how ants respond to a fellow who seems completely normal most of the time, but who sometimes starts flipping-out and sliding around crazy a la “The Exorcist.” The ants treat the magnetic ant completely normally until she freaks out, then they pounce and start biting her head. After the freak-out, they keep biting for a little bit, and then let go, and everything’s back to normal. On top of visuals I provide a andy’s-been-programming-too-long crazy narration of the events 🙂