Nevertheless, it wasn’t too long before the belly of the rainforest opened up, a consequence of the canopy depriving sunlight from reaching the forest floor. Small shrubs, ferns, and palms managed to thrive in the shadowy world, as did the moss, herbs, and fungi that coated the spongy ground and decomposing deadfall in shades of green. Higher in the dark understory, flowering plants such as orchids and bromeliads, as well as edible fruits, flourished. Vines and leafy creepers snaked their way up giant buttress roots and ancient tree trunks, searching for a way out of the gloomy dungeon in which they’d sprouted. Woody lianas, some hundreds of meters in length and as thick as telephone poles, coiled in gravity-defying loops from tree branches, linking them together to create a canopy superhighway for arboreal animals.

On first glance, the dusky emerald forest seemed tranquil and harmonious. In reality, a ruthless, invisible war was taking place, only at a pace too slow to see with the naked eye. Some species of trees regularly dropped their fronds and branches in an attempt to rid themselves from the freeloading, light-stealing lianas; other species swayed out of phase from their neighbors to snap the smothering vines and creepers; and still others had evolved peeling bark to shed cumbersome epiphytes, or produced toxins to ward off infestation by pests. Yet perhaps nothing illustrated the dog-eat-dog world better than the giant, prehistoric-looking strangler figs, parasites whose aerial roots encased their host trees in a living mesh, squeezing and killing even the largest victims before growing over their corpses to become colossi themselves.

Marty called a break before one such strangler fig, its roots merged into stout pillars as thick as English oaks. He swatted at a wasp flying uncomfortably close to his head. The drone of its wings was especially loud in the still, hushed forest. The silence was unnatural and disturbing; it was the silence of being watched by unknown eyes, as if all the creatures of the forest had stopped whatever they were doing to take stock of the interlopers.

Rad and Jacky sank down on a mossy log.

“Do you want bug spray, Marty?” Rad asked, rooting through her bag.

“If you two haven’t noticed,” he said, “our path has disappeared, which means unless we start leaving a trail of breadcrumbs, we’re going to have a heck of a time finding our way out again.”

“You want to turn back already?”

“I’m saying we don’t have a choice.”

Uncertainty hung in the warm, wet air as Rad and Jacky weighed their options. Marty took the can of aerosol insect repellant that Rad had produced and sprayed himself in a cloud of chemicals.

Rad said, “We were hoping to find a waterhole to swim in.”

Marty shook his head. “We have no path to follow. We can’t see the sky. If we get turned around, we could become hopelessly lost.”

Jacky said, “Maybe he’s right…”