March 23, 2012
I have been rolling the words, Arachnocampa luminosa, a lyrical mouthful, on my tongue all week— ever since I returned from a visit to the Kawiti Caves. Several million years old, the caves were discovered in the 17th century and are still owned by the descendants of the original Maori family. The walls of these caves contain massive pillars of sandstone and pure white limestone— stalactites and stalagmites growing at the rate of an inch every one hundred years, sometimes into recognizable shapes—the fronts and rears of elephant herds, a polar bear, a bearded man, and more, if you use your imagination.
As if that wasn’t awe inspiring enough, the ceiling of this pitch black cave was magical because it has been home to constellations of slender worm-like larvae that glow like stars in the Milky Way. Walking by dim lantern light, the ceiling was, at times, low enough for me to almost touch a star.
Even at the highest points the “stars” were a mere 22 yards away. Deep in the inky black cold interior, with the lantern extinguished, I stood wrapped in a shawl, conversing with Orion. Some of the larvae-stars were as bright as the North Star; others less so, although they were all lodged on the ceiling equidistant from my eyes. Why? “Because,” said our guide—a sweet 12-year-old Maori boy—“the hungrier the larvae, the brighter the light, and when they’re full, they turn off the light and sleep.”
And then, he gave us a little science lesson which just warmed the cockles of my heart! I had smiled at him when he pronounced the glow worm’s multisyllabic name correctly in his beautiful Maori accent. Now, like the glow worms, I beamed when he said the larvae glow because a waste substance produced in their bodies, luciferin, is converted to a biofluorescent blue-green substance in the presence of oxygen and energy (ATP).
Andwhere do they get their energy from? From food, just like us, the boy said, which is why they have to catch insects. And so, like fishermen, the larvae sit on the ceiling and cast their nets—vertical, silvery sticky strings that dangle down like a pearl necklace, to which unsuspecting insects cling, and are reeled in for supper. Thin as sewing needles with blue-green tail lights, the larvae grow from a speck (one hundredth of an inch) to a whopping inch and a half. That’s a lot of glowing!
By this time, I decided I’d like to be a larva-star. Glow, eat, and sleep—what’s not to love? But then, my little Maori friend said, Arachnocampa luminosa’s life span from egg to adult was just 10-12 months! I didn’t like that at all. And the glow worms weren’t even worms. The eggs would hatch to be these voracious larvae-stars that would live for some 9 months, metamorphose to pupae and then on to unattractive flies that would live for a mere 3-5 days because they have no mouths to eat. That was really discouraging. In fact, their sole purpose was to mate and lay fertilized eggs, or worse, just lay unfertilized sterile eggs, if no males were around.
No, I thought, no—this was much too bleak. No stardom for me. I would just go back home and settle for being a writer on a shoe string.
(Photography is not allowed inside the caves. All pics are taken from the internet.)