That’s just your science

An article over at Wired talks in detail about the overblown reputation and fears of the notorious brown recluse spider (Loxosceles reclusa) and, as is so typical of any attempt to impart some needed perspective to the general public, it crashes like a wave against the rock of human nature – at least, if you consider the comments to be a reliable metric, which is likely a bad move in itself. Still, it illustrates a very common trait, one that works against us so often that I want to highlight it (again.)

Short synopsis of the article: brown recluse spiders are rare in a large number of the states they’re reputed to be within. Misidentification of the spiders themselves is common. Misidentification of myriad forms of skin ailments as being the bite of a brown recluse is common. Worrying about them as a dangerous species demonstrates poor perspective. And, an observation of my own, reflected in even giving this synopsis in the first place: providing links in posts to helpful, detailed sources of greater information is often a waste of time.

Because, within the comments, the accusations of how wrong the article is in one aspect or another are flying fast and furious, or ‘speedy and spurious’ if we want to subvert a silly phrase. The range is incorrect, they can travel all over the world in boxes, I can see the evidence of bites on numerous shoppers in my local store, and so on. One of the most detailed points in the article – that the folklore of the spider is mostly dead wrong – gets trumped by the personal anecdotes of far too many commenters [small pet peeve appears here: ‘commenter,’ as in, someone who comments, is not considered by either my computer’s dictionary or Merriam Webster to be a proper word – the only word that means the same thing is ‘commentator,’ which is stupid, because that word is used only for someone who is paid to blather meaninglessly and nobody is ever said to ‘commentate.’ We need to keep using ‘commenter,’ in recognition of common language rules, and force the dictionaries to keep up.]

Ignoring my petty irritations, the power of the personal anecdote is stunning, and unfortunately way out of proportion to its actual value. It’s very plain how many people are completely willing to trash the entire article because of their own experience, or even that of another commenter, immediately after reading that such anecdotes are wildly inaccurate. There is even the not-so-subtle implication, highlighted in bold face in an excerpt, that the allure of drama skews such anecdotes to be even more unreliable:

“If you get a bacterial infection, do you tell anyone about it? Of course not,” Vetter said. “But if you think you got a brown recluse bite, you tell everybody! You put it in your Christmas letter.”

And yet, this is somehow missed by, no matter how you measure it, far too many commenters.

GritspiderNow, let me introduce a few points. I am, among other things, a spider photographer, which means not only do I have close contact with them very frequently, I also seek them out, and look closely at any I might stumble across, and that’s nearly daily. There is not any experience of mine that I can point to as definitely a spider bite, though I am chewed up routinely by mosquitoes and other various parasites, not to mention encounters with bees, ants, and even caterpillars. I might have found a brown recluse once, in my apartment in North Carolina (outside of the mapped range in that article,) but did not get any photos – I know from experience that identifying arthropods is a tricky business, and I did not make enough observations to pin down all of the telltales of the recluse or even the greater family. One commenter claimed that they can spot brown recluses in their vents with a flashlight because their eyes reflect, but that’s true of many spiders, including the one shown here, only a few millimeters across and definitely not a recluse, or even close.

So when I tell you that the article is accurate, well, you hopefully already caught that the entire above paragraph (as well as most of this blog) is anecdotal, and just one uncontrolled data point to be weighed against the studies quoted in the article, using a large variety of data sources and numerous actual specimens examined by qualified entomologists. The weight of any of my statements? Not much at all, really, and certainly no more, or less, valuable than any of the comments on the article. Anything I say needs to be measured against how many ways I could be wrong or mistaken. My biggest point is, of course, that while I refer to my potential inaccuracies, this same potential applies to most such anecdotes that anyone might hear, anywhere. That’s the key thing to remember: one data point, with a confidence value that cannot even be calculated.

And then there’s our old friend, confirmation bias. Even if any of the commenters are entirely correct and highly accurate, this does not negate the points in the article, much less the studies it is based on, in any way. A house full of confirmed brown recluse spiders in Alaska does not mean the state can now be considered part of their range, any more than the NC Zoo proves that puffins are native to North Carolina. You can find commenters referring to necrotic wounds as evidence of brown recluse populations, despite the very clear information within the article that necrosis is not limited to brown recluse bites, and in fact not even typical.

Confirmation bias is the golden child of pseudoscience, but it can be seen everywhere. As I’m fond of pointing out, we don’t give much credence to our neighbors when they tell us of their youthful exploits, sports accomplishments, or value in the workplace – fishing stories, in other words. But when it comes to confirming something we want to believe, oh yeah, then they’re a solid source of information, and even questioning this is often challenged with, “Are you calling them a liar?!?!?” Yet our desire to be vindicated in our beliefs does not give greater accuracy to any statement supporting said beliefs. This is, in fact, when we should be more suspicious, just because we’d love to be proven right and thus play favorites with the evidence – this is even a common warning in scientific fields.

Another consideration is sample size and representation. While I can point to the comments on that article and even count them up according to whatever broad categories I choose to define, it doesn’t mean that I’ve produced reliable data. Not everyone reading is commenting, obviously, and not everyone who came across the article even bothered to read it; by nature it may attract arachnophobes solely because it denies their fears, even in the title, so the negative, defiant nature of many comments would be virtually guaranteed regardless of the points within the article. Then we have to consider how many people skim articles or do not retain every detail within, and thus respond based on incomplete info – reflecting not stubbornness when they miss any point, but mere oversight. This means considering such comments as representing the overall populace is unwarranted, and likely very inaccurate.

Finally, we have a perspective not touched on in the article. The chances of a fatal auto accident are exponentially higher than any illness caused by bites of anything, and this never stops us from driving anywhere – we accept these risks readily even when we know of someone who died in an accident, and the rationales we use are plentiful. Using myself as an example, I receive the most injuries from working on the cars or doing larger projects, and even the smaller projects often produce some damage to my hands – it’s just the price paid. Bodies heal. Now, I can still speak of the immediate kneejerk reactions of arachnophobia, despite knowing that the risk is trivial – I can pick up a modeling knife without qualm despite nearly every finger bearing scars from one, but cannot let a large spider walk across my hand. Rational considerations do not easily overcome phobias. However, the key point about phobias is recognizing that they’re irrational fears, way out of proportion to the risks, and strictly personal. Using them to dictate behavior beyond the reflexive is the very definition of irrational, and not a justification as so many people tend to think.

But this still tells me I should probably finish up my proposed school presentation on critical thinking, because the habit of maintaining a critical perspective cannot start soon enough.