Club Ochroma is the bar of choice on Barro Colorado Island, and I've arrived a little early for happy hour at the Smithsonian Tropical Research Station. It's 3:45 in the afternoon, and I'm perched on a hundred-foot makeshift tower overlooking a scruffily majestic Ochroma pyramidale tree of about the same height. More commonly known as the balsa tree, Ochroma is found in many Latin American countries and is the source of the lightweight wood used to make snap-together model dinosaurs, Popsicle sticks, and Thor Heyerdahl's Kon-Tiki raft.
My noble specimen, however, is decidedly pre-lumber, and its branches sag with hundreds of blossoms at varying stages of ripeness: the buds that look like giant brown Q-tips, the unopened volutes with their creamy heads like swirls of soft-serve vanilla ice cream, and the mature flowers, which bloom at night and so are just now spreading wide their five fleshy petals to reveal a pollen-covered stamen surrounded by an inch-deep pool of rich, syrupy nectar. Wider, wider
A crash of understory, a volley of yeeps, coos, and chutterings, and sure enough, it's the capuchins. Capuchin monkeys are famously shrewd and resourceful primates, the New World equivalent of chimpanzees. And when happy hour rolls around in Panama, you'd better believe their bellies are the first at the bar. Twenty-five of them arrive in conga lines to claim the opening rounds, the unencumbered adults and brash teenagers up front, the mothers with their clinging babies at the rear. Whatever their age or sex, the monkeys all have naked white faces, big humanlike ears, and the pursed, fretful expressions of old shopkeepers. A few stop to flash me an aggressive simian smile, but most get right down to business. They grab the edges of the ripe flowers, stick their heads inside, and with the hunched intensity of vampires, drink the flowers dry.
When they look up again, their muzzles are speckled with pollen, which from the tree's perspective is the whole point of its flowers: to capture the attention of a pollinator long enough that the animal can't help but be brushed with the plant's equivalent of semen, which, if all goes well, the inadvertent matchmaker will eventually deliver to the female parts of another balsa tree's flowers. The exchange is simple: You get drinks on the house, my gametes get a ride on your face.
The sun sinks, a pair of toucans passes noisily overhead, and the diurnal monkeys begin wandering off, heading back to their nests for the night. They were greedy and sloppy, but the tree is unfazed. It promptly refills pawed-over flowers with a fresh supply of nectar and nudges other blooms to unfold. Ochroma is just getting started.
Throughout the night and into the next morning, the trees here and on the mainland nearby will play host to an unusually large and pan-Linnaean cast of characters—mammalian, avian, amphibian, insectile. A few of the customers look familiar: A close cousin of the opossum often seen bumbling around trash cans in the United States turns out to thrive in the tropics and to love the taste of Ochroma juice. Others are gorgeously obscure: If you were to catch a rare glimpse of the olingo, a distant relative of the raccoon, as it slid silently through the branches like an oil spill with feet, you'd realize how alien our planet remains, how poorly we understand its parts.