Current Events

Three Reasons Why Spiders Can’t Burrow Through Human Skin

Australia's redback spider (Latrodectus)


Yesterday, you may have seen this amusing-yet-dismal failure of the news media. Hundreds of outlets breathlessly reported a tourist’s tale of a skin spider plowing a pustulated trail through his belly. Snopes dissects why the story is bogus; essentially, the sole source is the tourist himself. The poor kid was likely told he had scabies mites, or similar common affliction, and not knowing what a mite was he settled on the nearest arachnid he recognized. That, plus ingrained cultural arachnophobia and a media disinclined to turn down click revenue over such a silly matter as ethics, and the story goes viral.

Shoddy journalism aside, there is no plausible reason for any spider to burrow into skin, and no physical attributes that would allow them success at it, either. Spiders can’t do it for the same reasons giraffes can’t hover: the laws of physics just don’t work that way, not for the way spiders are built. Here are a few reasons why the story simply could not have happened as reported.

1. Spiders are active animals that need to breathe. That’s hard to do when trapped under skin, and spiders lack the breathing tubes of real skin-burrowers like botfly.

2. Spiders are too delicate. Animals that burrow are strong, compact, and stubby. Think of the bullet-like build and short, powerful legs of a mole or a wombat. Serious burrowers like earthworms lack legs altogether. What’s a spider? Pretty much the opposite. Inconvenient legs everywhere, and far too spindly and weak to burrow. (A few spiders do make soil burrows, but soil is a rather different and more forgiving medium).

3. Spiders lack an implement for opening a suitable entry hole. Spiders have fangs, which are thin and sharp and can appear scary, but if you’ve ever tried to dig a hole using only hypodermic needles you’ll appreciate the uphill battle a spider faces.

Also, there has never been a single confirmed observation of a skin-burrowing spider.

So, no. You don’t have to worry about skin spiders.

More On Pest Control Advertising: Orkin Takes The High Road

Meanwhile, Orkin- that other pest control giant- adopts a softer, more subtle marketing strategy.

Screen capture from Orkin’s website, displayed without permission as Fair Use commentary on Orkin’s marketing strategy.

Many people are reluctant to call pest control, perhaps because decades of environmentalism has softened our cultural attitude towards nature, or perhaps just out of guilt towards the wee household insects. In contrast to Terminix’s brute force fear campaign, Orkin projects a feel-good “Bugs are cool, but sometimes we do have to kill them”. I suspect this appeals to a great number of homeowners on the fence about whether they should use a commercial exterminator.

Of course, a company’s marketing front has little to do with the quality of the job they actually perform, so don’t take this as a recommendation.

(Disclosure: Orkin has purchased image licenses from me in the past, but has also used several of my photographs without permission. My relationship with the company is complicated…).

How To Lie With Pest Control Marketing

Few major pest control companies are as awful in their marketing as Terminix. Consider:


[2011 advertisement for Terminix]

The message is clear: Ants give you diseases, and our company can get rid of them for you.



Let’s be clear about the scare term “carrier”. Terminix would like us to think ants are carriers in the epidemiological sense- like an infected Ebola patient boarding a plane. But that’s a semantic sleight of hand.

The research on the topic of ant-borne diseases is rather more mild. Ants are only “carriers” in that they can physically transport bacteria found in the environment. That’s not surprising. Most things transport bacteria. Your shoes, for example, are excellent carriers of strep, sensu Terminix. Your own hands are even more effective.

Merely carrying bacteria, which everything does anyway, is a different matter than being effective at causing disease. And the evidence that ants are actually dangerous as infectious agents, rather than just theoretically so, is so weak that there are precisely zero known cases where an ant has ever infected a person with strep, staph, or salmonella.

Antweb’s AntBlog explains:

 …if an ant walks through an area densely populated with infectious bacteria, they track it along in quantities large enough to show up in a petri dish.

The good news: Petri dishes don’t have immune systems. The quantities of bacteria ants transport and slough off as they saunter across your counter tops will probably be small compared to the infectious dose for healthy humans. The quantities of bacteria that remain on the ants’ feet after taking the thousands of little ant-steps between a source of infection and your table would presumably knock off the vast majority of the bacteria, leaving too few to constitute an infectious dose.

So what I’m trying to say is: thought it is theoretically possible for ants to transmit infectious bacteria to humans, as far as I’m aware (other members of this blog, please speak up if you know better!) there are no records of ants being definitively implicated in someone catching a disease. As best as I can tell, all of the articles that reference ants’ potential to be vectors for infectious bacteria are based upon laboratory studies in which nothing besides some agar in a petri dish got sick.

Absent evidence of any real health threat, Terminix is just trying to scare you out of your money.




The 2013-14 eastern monarch butterfly numbers are inconceivably awful. Horribly, terribly, awful. The population declined significantly beyond even last year’s dismal showing. Essentially, the eastern migratory population is collapsing.

This sucks.

The monarch butterfly is an iconic insect. It is the standard butterfly, frequently modeled for logos, costumes, and symbols. Children across the continent raise the caterpillars, and for many young people, monarchs are their first meaningful contact with arthropods. These insects are as culturally significant as they are ecologically. If something isn’t done soon and done big, the monarch migration will go the way of other animals with which it used to share the prairies- the herds of bison, the passenger pigeon.

I don’t have many photographs of monarchs. A few bland shots of larvae, a handful of adults on flowers. I never felt any urgency. They were as common as dirt. I just sort of assumed monarchs would always be around to photograph later.

Silly me.

The Midwestern Dead Zone




We may not think of destruction as we drive through its green fields of corn and soybeans, but the midwestern United States is as damaged an environment as anywhere in the world. The demolition was swift and complete. Within 100 years of the discovery that prairie soils could be farmed, 98% percent of the tallgrass prairie that covered the center of the continent was gone. In the place of rich native flora, we have corn, soy, and a handful of agricultural weeds. Functionally, biologically, the midwest is deader than a parking lot.

See those dark green areas in the map? Those are corn and soy. Statistically speaking, nothing else lives there. It is dead.

When we talk about planting milkweed to save the ailing monarch butterflies, or adding flowers to our yards to support the bees, we’re just fiddling around the margins of the 2% of whatever is left. Sure, smart gardening helps. But only in the same way as spritzing a squirt gun vaguely in the direction of a burning building. The midwest is dead, and will remain dead, until a significant chuck of farmland is converted back to natural habitat.

Crazy ants, the New York Times, and the failure of Americans to support basic research

Nylanderia fulva


I’m annoyed at this New York Times profile of the Nylanderia fulva invasion:

Even when the government did look straight at the ant, it didn’t know what it was looking at.

Tom Rasberry collected samples of the ant at the Pasadena chemical plant in 2003 and sent them off to a lab at Texas A&M to be identified. But taxonomy — the process of ordering living things into species — is arguably more an art than a science, and figuring out what species the ants were, and where they came from, quickly became vexing. Academics from other institutions swarmed in to debate, for example, the significance of four tiny hairs on the ant’s thorax. For years, they hurtled through a series of wrong answers, but the consensus eventually leaned toward a certain invasive ant, called Nylanderia pubens, which has been in Florida since the 1950s.

This is not accurate. Scientists did not, in fact, “swarm in to debate”. The slow response to identifying N. fulva was exactly the opposite. The trouble is that figuring out the origin of invasive ants isn’t anyone’s job. At least, not in the United States. What happened was that a few ant scientists, in their spare time from whatever their official duties were, have occasionally offered an opinion about these new invaders.

Exterminator Tom Rasberry, who discovered the invasion, sent specimens to Texas A&M. No one at Texas A&M has expertise to deal with Nylanderia. And of course they don’t. Our planet holds millions of insect species, and any one person can only master a few hundred. Experts on any particular group are few and widely dispersed. In fact, there are really only two people in the United States with appropriate experience to address the crazy ant problem: James Trager and John LaPolla.

James did his PhD on the taxonomy of these ants in North America in the 1980s, back when most species were still considered Paratrechina. He had even looked at an earlier incidence of crazy ants in Texas, and contra the New York Times’ insistence that only the Good Ol’ Exterminator boys in Texas had figured it out, James determined that the Texas and Florida ants were different species. Yet James never found taxonomic employment, and went on to work for the Missouri Botanical Garden as a staff naturalist. Ant identifications are not part of his job description. He does them now as a hobby.

John is part of the most recent team to work on Nylanderia, the one that actually located the South American origin of the invasion. He works in a primarily teaching position at Towson University, and like James, identifying invasive ants is not part of his job description. He is allowed to research what he wants to, and we are fortunate he picked up Nylanderia out of curiosity.

I don’t see the point of singling out the egghead scientists for being slow to identify Nylanderia fulva when the real trouble is bigger and structural. Americans simply don’t value basic research enough to support a system that rapidly pinpoints emerging pest problems.

If we want to quickly identify new pests, we need to salary thousands of positions for taxonomists where rapid response to emerging threats is part of the job. Instead, we’re doing the opposite. Taxonomists are being laid off. Congress is defunding science. The result is that when a new problem like invasive crazy ants arises, we depend on retirees and hobbyists to volunteer their expertise, if they want to. As a response to billion-dollar invasions, that’s just not good enough.

Tick Season, as measured by Google


(via Google Trends)

I’m not generally one to extol the virtues of enormous corporations, but one thing the tech giant Google does right is to share freely much of their bank of search data. Google Trends picks up tick season like clockwork, and searches for “ticks” peak reliably every May when North Americans find the little arachnids in numbers on their dogs and on themselves.

I bring this up as a long-winded way to point you to bug guy Eric Eaton, who has just posted an excellent, concise summary of what everyone who lives near ticks should know about the animals. Go read.

A questing dog tick, Dermacentor variabilis