DrugMonkey tells a tale of a specific finding in addiction research — that rats provided with an intravenous drip of cocaine solution will push a lever to self-administer the drug — which has been replicated countless times over the decades. Past the point of usefulness, you’d think. But it turns out that in all this replication, folks have turned up a lot of factors that make the replication, um, not replicate. Everything from the cocaine dose available in each infusion to whether or not the rat-handler wears a clean lab coat.
And this, as he concludes, has taught addiction researchers a lot about the mechanisms underlying a seemingly unassailable “classic” result.
I can’t speak to how many “failure to replicate” studies were discussed at conferences and less formal interactions. But given what I do know about science, I am confident that there was a little bit of everything. Probably some accusations of faking data popped up now and again. Some investigators no doubt were considered generally incompetent and others were revered (sometimes unjustifiably). No doubt. Some failures to replicate were based on ignorance or incompetence…and some were valid findings which altered the way the field looked upon prior results.
Ultimately the result was a good one. The rat IVSA model of cocaine use has proved useful to understand the neurobiology of addiction.
Science! Where you learn things even when you screw up. (Maybe especially when you screw up.)
It left me wondering, though, what the equivalent experiment or result would be for my own field, population genetics. My first thought is isolation by distance, the finding that populations distributed across a landscape will show greater genetic differentiation as the geographic distance between them grows, even if there is no meaningful difference in the environments they encounter. Testing for IBD is a terribly basic thing to do with your shiny new population genetic dataset, and it’s no surprise when it turns up — but if you don’t find it, you know something odd is going on.
Or maybe there’s a better alternative that I haven’t thought of? Submit your nominations in the comments.