What’s in a Name?

Early in the academic year, I led my junior-level biology students into the forest behind North Cross School to identify some of the native flora and fauna on the campus.  At one point, I picked up a wriggling daddy-longlegs, or harvestman as they’re more properly called, and showed it to my young scholars, using the animal as a “teaching tool” about the natural history and ecology of arachnids.  Bright-eyed and full of questions, one high-schooler inquired, “Dr. Rinker, is it true that daddy-longlegs have the most potent venom for their size of all spider relatives?”  I replied, “No, it’s not true,” much to her disappointment.  In fact, the daddy-longlegs native to our Virginia woodlands does not have venom glands or fangs.  For an odd little critter that looks like it’s straight off the pages of Dr. Seuss, the harmless daddy-longlegs seems to have inspired much angst among outdoor-goers.

How then did such a specious myth originate about this inoffensive creature?  As it turns out, it’s mostly in a name.

In the mid-18^th century, well into the Age of Discovery, ships returned from the New World, laden with riches that included never-before-seen flora and fauna to enthrall Europe’s centers of learning.  Tobacco, maize, potatoes, orchids, butterflies, beetles, parrots and monkeys were just a few of the thousands of specimens – live, pickled, stuffed, and fossilized – that captured the attention of Old World intelligentsia.  An immediate problem was, of course, what to name all these curiosities?

Carl von Linné, a Swedish scientist concerned about the cumbersome taxonomy of his day, decided to streamline the process of naming new species by ignoring common names and applying a unique Latin binomial to each newly described type of organism.  For example, it was Linné who gave humans the scientific name, Homo sapiens (literally, “Man the wise,” a rather exalted epithet that we have not always deserved).  Common names were ignored because they vary from region to region and from culture to culture.  A robin in America, for instance, is not the same bird as a robin in Europe; their respective scientific names (Turdus migratorius and Erithacus rubecula) tell us this clearly.  On the other hand, a white oak in North America (Quercus alba) is closely related to a red oak in Costa Rica (Quercus costaricensis) because they have the same first name.

Always in Latin, even when the vernacular is Chinese or Russian, the scientific name of an organism is a noun followed by an adjective: much like other Romance languages such as Spanish and French.  An ancient Roman would recognize their common lineage just from their respective names!  Taxonomy then is one of the tools in the proverbial toolbox of us scientists to show evolutionary relationships among the world’s known species.

What does all this have to do with the daddy-longlegs you ask?

In the scientific literature, the innocuous daddy-longlegs in the Roanoke Valley is known as Phalangium opilio.  With no venom glands or fangs, this species is an opportunistic predator and will even slurp plant juices.  Other so-called “daddy-longlegs” are fragile, web-weaving spiders distributed worldwide, such as cellar or pholcid spiders (Pholcus phalangioides) – or are gangly non-biting crane flies, which are not spiders at all but insects related to the common house fly.  (The term, daddy, is an old-fashioned British reference to long-legged flies; it was used in Edward Lear’s 19^th-century nonsense poem, “The Daddy-Longlegs and the Fly.”)

Though cellar spiders do have venom and venom glands, their short fangs would prevent them from penetrating human skin even if they did want to bite us.  Thus, no reference exists to show any pholcid spider biting a human and causing a detrimental reaction.  So, if our daddy-longlegs is harmless and other “daddy-longlegs” species are also harmless, then why this myth about their alleged venomous nature?

Apparently, the urban legend about daddy-longlegs stems from the fact that pholcid spiders are known to prey from time to time on deadly venomous spiders such as members of the genus Latrodectus (also called the black-widow genus).  I guess someone extrapolated that, if a daddy-longlegs could kill another spider capable of delivering fatal bites to humans, then it must be even more venomous than its prey.  There’s nothing special about their venom, however; they just work more quickly than their quarry.

Sadly, the extrapolation was espoused by a few lurid television producers, fringe reporters, and incautious teachers; and the rest of the story, as they say, is history.  If folks had minded the scientific names rather than the common names, and learned a little about the ecology and natural history of the various “daddy-longlegs” throughout the world, no responsible person would have promoted this unhappy error.  Unfortunately, here in the Roanoke Valley, our little spindly spider-relative is now the occasional object of unbridled derision and wariness despite its helpful nature as a generalist predator on arthropod pests.  It’s all in its common name.

As a scientist, I am fascinated by the power of myths, dreams, fairytales, and archetypes in their cultural settings.  Not just the naughty antics of the Roman pantheon, however, or the wicked imaginings of the Brothers Grimm.  I am also intrigued by make-believe stories about the natural world that become embedded as cultural truths handed to the next generations as important lessons about life.

On one level – a scientific one – this claim about daddy-longlegs is downright false.  On another level, however, no myth emerges ex nihilo.  Somebody observed something and later told a tale that linked that observation with that conclusion.  We scientists call this linkage between two events, related or unrelated, occurring together a “correlation.”  And correlations often get us into all kinds of trouble – as manifested in other, but equally counterfeit, nature myths:

• Ostriches stick their heads in the ground when they’re frightened.
• A toad or frog that urinates on you will give you warts.
• Bats are blind, and they’ll fly into your hair.
• Elephants are afraid of mice.
• Dogs see only in black and white.
• Eating turkey makes you drowsy.
• People only use 10% of their brains.

Perhaps in a later article, I’ll expose the fictions in these enduring urban legends.  But my hope for this article is to correct an injustice toward our little Dr. Seuss character, the omnivorous harvestman that helps to maintain healthy forests.

Charles Dickens began his 1859 historical novel, A Tale of Two Cities, with the following declaration: “It was the age of wisdom, it was the age of foolishness, it was the epoch of belief, it was the epoch of incredulity.”  He could have been describing our own time – minus the guillotine, of course!  The natural world is filled with such amazement that I wonder why we feel obliged to add our own myths about its rich biodiversity.  Spiders and their relatives serve an important function in the economy of nature: it’s Mary Howitt’s “The Spider and the Fly” meets E.B. White’s “Charlotte’s Web.”  Yes, they can appear bloodthirsty, creepy, shadowy.  But these adjectives are our imposed perceptions on them, blurring reality.  Let’s focus instead on their remarkable ecological benefits and debunk their myths wherever we confront them.