Story by Paul Wood
Photo by David Liittschwager
There are 40,000-plus species of spiders on Earth, and nearly every single one of them gives people the creeps. Arachnophobia (fear of spiders) is one of the most common fears among humans, but there is one spider that gets called “cute,” “adorable” and “carefree.” We emblazon its image on T-shirts and caps. It isn’t fair, really. We detest 39,999- plus spiders, but this one, we seem to assume, drew a smiley on its back for the sole purpose of reminding us to have a nice day. What else could we call it but the happy-face spider?
But the truth about this spider (which has a far more serious scientific name, Theridion grallator) is more interesting, more puzzling and—yes—more lovable than appears at first glance. The happyface spider is one of the many reminders that the native Hawaiian wilderness is chock full of information about evolution, genetics and biology. An endemic Hawaiian species, it is found nowhere on Earth except in the undisturbed upland forests of O‘ahu, Maui, Moloka‘i and Hawai‘i Island. It is common around Thurston Lava Tube at Hawai‘i Volcanoes National Park.
Just five millimeters long—less than one-fifth of an inch—the happy-face spider likes to live on the underside of a single leaf, which it rigs with a slight, almost invisible web. It sleeps by day and gets active at night, darting forth to grab infinitesimal insects, which it consumes in the usual spidery way by liquefying its prey with digestive juices and then slurping the results.
The happy-face spider belongs to a large spider family called Theridiidae. These spiders build cobwebs—loose, tangled constructions—and include a variety of house spiders, most notoriously the black widow. But the happy-face, nonaggressive by nature, is utterly harmless to gigantic mammals like us.
There is both passion and tenderness in the life of the happy-face. To get the story you must remember that spiders, like insects, live within their own exoskeleton, an armorlike skin that they must occasionally shrug off so that they can grow, suddenly, to their next size. During these periods of skin-splitting, or molting, the spiders are soft and vulnerable. When a male happy-face is ready to make babies, he will search for a female that is ready to molt, and he will stand guard to protect her. When she is quite soft, he will do the deed, placing his charged palps (which look like swollen drumsticks on the front of his head) inside her etigynum (a little pocket). Afterward he loses interest in living while she grows large and aggressive. She’ll lay a pile of eggs, cover them in silk and defend them against anything that moves. When the babies hatch, she’ll pull the silk apart to release them, then feed the spiderlings with her own liquefied diet. This extended parental care is a rare phenomenon among spiders.