While Prof drank his tea the next morning, I examined the snare. Making it must have taken a lot of effort; it had an elegantly carved disc of wood at its center, with fasteners of the perfect thickness for the vine to slip through. But that work had paid off — I remembered how easily I’d been hoisted into the air, the amount of force the simple device had been able to muster. The snares spent their existences like I’d spent mine, announcing themselves only in the quietest moments.

The moment Prof had finished his mint tea, I eagerly led him toward the spot on the faint trail where I’d heard the chimpanzee scream and crash away. He pulled us short well before we got to the site. “Look,” he said, grabbing my arm and whirling.

It was a dead body.

The skeleton dangled from a wrist, still striped with sinew and scraps of skin and straight black hair. At first I thought someone had hung a human skeleton from a tree to warn us. But then I realized it wasn’t a human and that it hadn’t been hung; it had been trapped. The liana vine was older and brown this time, but I recognized the snare’s knots.

“Is that a mock man?” I whispered.

Prof nodded sadly. “Yes. It was a chimpanzee. Do you still have the knife on you?”

I nodded, then climbed the tree and cut the skeleton loose. It clattered to the ground, flies and maggots and scraps of skin falling from it. Some rotted tissue opened up at the center of the corpse, letting out a terrible smell. I tugged at Prof’s sleeve. “We’ll be sick! There’s nothing you can do with the body.”

Prof dry heaved for a moment, then approached the corpse. Clutching the vine, he dragged the skeleton to the river and hurled it in. We watched it disintegrate in the current. When Prof returned he had tears in his eyes. “It is illegal to hunt chimpanzees! They are endangered! And this hunter set a snare that he didn’t return to. This chimpanzee probably took over a week to die from infection on its wrist. An exquisitely sensitive creature, with family and hopes, died a very painful, lonely death.”

I imagined hanging by my wrist from a tree, crying alone. The pain spreading from my wrist to my arm, watching my body rot until I died of thirst. That was often how I’d seen snared animal corpses for sale in Franceville: One limb had rotted too much to eat and had been chopped off. Even if these mock men were monsters, no creature deserved to die that way.

“It is awful,” I said.

“The irresponsibility of it,” Prof said. “We will find this hunter!”

“Okay, Prof. Of course we will,” I said quietly.

I thought Prof might want to return to camp after that, but he wordlessly pressed on.

Once we’d reached the clearing where I’d heard the chimpanzee, we stood still for a long time. Omar had followed us at a distance, emerging from the green and clutching my shirttail like Pierre once had; but he soon got bored, climbed a nearby tree, and nodded off. Prof was patient and still, staring into the foliage with intense focus. At points he rolled out his rug, kneeled, and prayed to his god. But even with the power of his prayers, no chimpanzees came.

“We must be very patient,” he said in a hushed voice once he was back up, shaking soil from the rug. “The chimps are smart creatures, and clearly they are already being hunted by humans. Why should they trust us, who are also humans?”

Asking Prof to stay where he was, I returned to the mango tree. There I gathered up more of the wormy fruit. Inspecting the mangoes, pink grubs waving from between the plates of their cracked skins, I realized they might be too far gone to attract any mock men. I let them fall with a wet thud, wiped my hands on my pants, and shinnied up the trunk until I reached a couple of choice ripe mangoes still on the branches. I got bitten by some insects as I scaled the tree, and already had a raised rash from a vine that had broken my skin as I rolled across it, but I thought these delicious fruits would be worth it.

When I returned to Prof, he realized my intention right away and nodded toward the far side of the clearing. Once I’d laid the fruit there in a small pile and returned, we stood behind a tree and watched.

All was quiet. Omar woke and chirped down at us, as if asking what was supposed to happen.

“Mangoes are not native to Africa,” Prof whispered. “Maybe the chimpanzees know this and do not like them.”

“I bet the chimpanzees don’t care where mangoes originally came from,” I said. “They care that they taste very good.”

But still — the fruit didn’t seem to be working very well so far. All that happened was a red-brown snake wandered across them, flicked its tongue into the air, and then disappeared into the brush.

“What if the mock men decide we are tastier than the mangoes?” I asked. “What if something is watching, waiting for us to be eaten?”

Prof considered my words. “All the literature I have read indicates that chimpanzees will not eat us.”

I gave him a long look, then returned my gaze to the mangoes. “Does Jane Goodall write books about —” I cut off.

The drumming was loud and purposeful, like a chief preparing his people for war. And it was getting louder.

I crouched as the noise approached, heart thudding. For many seconds in a row there would be no drumming, then it would start again, each time much closer than before. I pointed high when I realized nearby treetops had started trembling along with the thuds.

The shaking branches were no more than a dozen yards away. Alarmed, Prof clutched my forearm. Then all was still.

Until a mock man came into view.

He was low and muscular, stiff black hair messy over a tan face and pouting pink lips. Easing forward on all fours, he sniffed curiously at the pile of mangoes. When the chimp grunted, Omar bounded to the top of the highest tree. He was a smart monkey, choosing a thin branch where it would be impossible for the heavier animal to follow. The chimpanzee’s attention snapped to the vervet. He stared at Omar for a few seconds, then brought his attention back to the fruit. Before taking any of the mangoes, he approached a nearby kapok, which he drummed by going into a half handstand and flailing his feet against it. It was a loud, impressive sound, and the chimpanzee paused to look at Omar, as if to see whether the monkey had been as awestruck as he ought to be. Making soft hooting sounds, the chimp drew nearer to the mangoes.

The chimpanzee was shorter than me, but his hands made deep indentations in the ground, so I knew he was heavy and strong. Though he mostly walked on all fours like a beast, occasionally he would stand on his two feet to look around. Then he’d go back to walking along the narrow forest path. The chimp seemed to have forgotten about the mangoes, and didn’t appear to have anything else to do with himself. He sniffed a branch and grasped along it to pluck a single berry. His hairy black fingers drew the red treat close to his lips. There were more berries on the branch, but he didn’t bother with them, instead plopping down in the grass, head resting on his joined palms. He looked like a boy kicked out of his home for the day, walking the streets and looking for trouble so he’d feel part of something.

I thought Prof might take his notebook out to make notes, but he was quietly watching the chimpanzee, face full of joy. He’d gone so long without blinking that tears were falling down his chin and dripping to the ground.

As he sat, the chimp held one of his feet to his nose and sniffed it; I saw that the bottom of his foot had no hair on it and was as brown-orange-pink as a person’s.

He lay still for a minute or two, then unexpectedly took off at a run. When he tripped over the pile of mangoes, he skidded to a stop and peered at them. After scanning the scene like a burglar, he placed one in his mouth, easily biting through the tough skin. The others he piled into his arms. Then he hurried away.

“Come on,” Prof said once the chimp was out of sight. “We’re following.” He took off down the path, moving surprisingly fast considering his limp. I trailed a safe distance behind, Omar bounding down from the tree and holding tight to my shoulder. We must have looked like nervous children trailing after Father.

Prof led us fast enough to keep the chimp in view, tracking the black figure against tangled flashes of green and brown. One time the chimpanzee halted and looked back at us, his black eyes meeting ours, but he didn’t seem alarmed; he clutched his mangoes tighter and continued on. Eventually the chimp stopped in a clearing and began hooting. Prof and I froze at the opposite end, hiding ourselves in the greenery as best we could.

The chimp held still, his hoots softening. While we waited I idly kicked at one of the large flat tree wings — and it made no sound at all. The chimpanzee must have been incredibly strong to make that drumming noise.

I decided to call him Drummer.

There was an answering chimp cry nearby, and then Drummer shot out of the clearing. We rushed to follow, and when we peeked around the bend we saw him with more chimps: a female with an infant playing at her feet. I figured she was older, since her skin hung loose, with hairless patches. The infant seemed healthy, rolling around on the ground and insistently climbing up her mother to suckle, even though the old female kept casting her off.

For a while Drummer stood near the old mother, swaying, the stack of mangoes tight in his hands. Then he turned away from her, squatted, and began to chew through the mangoes. The female crossed in front of him. For a while she kneeled there, infant wrapped around her belly, and stared longingly at the mangoes. Drummer pivoted again so she was out of his view and continued to eat. Then the female lay on her back, arm flat out on the ground. While Drummer ignored her, she flicked her fingers against his back, trying to attract his attention.

I named her Beggar.

Once Drummer had finished his second mango, he placed his free hand, downturned, on top of Beggar’s. She panted softly and cautiously reached for one of the remaining fruits. Drummer continued eating calmly as she pulled it and then the other mango away from him. She bit into the thick skin and peeled, rapidly eating one and then the other. As the peels dropped, the infant played with them, tossing them between her hands. When her lack of coordination made them fall, she got down from her mother’s lap to retrieve them — kicking them farther away in the process. Then she returned and began to suckle.

I decided to name the infant Mango.

Drummer’s attitude toward the old female was so dismissive yet respectful that I guessed he was no longer a child but not yet an adult; I suspected that he was even her son. Prof and I didn’t dare speak and risk drawing attention, but I made mental notes of what I wanted to tell him so he could record them in his notebook. I wondered if this was a little family alone in the jungle, or if there were other chimpanzees nearby.

Prof refused to leave the trio all day, but at one point I got hungry, so Omar and I returned to the campsite. Some small, fat brown monkeys, like yams with arms and legs, were poking around our stuff. I chased them off. Omar scolded the intruders even louder than I, though never leaving the security of my shoulder. Once we were alone I cooked some more rice, indulging in salt this time to make the meal taste at least a little different from breakfast. Omar seemed to feel at home at the campsite; he climbed into the plastic basin and stayed there when I headed back to check on Prof.

Along the way I foraged more mangoes. We ate them in our hiding spot, watching Beggar and Drummer and Mango. The chimps were conscious of us, but didn’t seem wary. Maybe they had already been around humans. I made a mental note to tell Prof that later: The hunter might have been someone the chimps already knew.

Prof’s head bobbed as he ate his salted rice. We’d been in that clearing for hours, and squatting so long had worn on the old man — like all foreigners, he crouched on the balls of his feet, instead of on his heels as he should have done. I leaned in and risked whispering, “Do you want to head back to the campsite? I can stay here a while longer and remember everything I see.”

Prof shook his head, then reconsidered and nodded. He must have seen I was upset to be alone, though, because he leaned down to look right in my eyes, hands squarely on my shoulders. “I know it’s frightening out here. But if we lose track of the chimps we might not find any again for weeks. I need your help; do you think you can give it?”

I nodded solemnly. I didn’t want to separate, but I owed Prof everything. If he wanted me to do this, I would. I pressed the knife into his hands. “You should have this. If that hunter or Monsieur Tatagani comes to me, I can run. You can’t run from the campsite.”

“Monsieur Tatagani? He doesn’t know where we are, Luc,” Prof said. But he did take the knife, and limped back toward the campsite. When he was gone I felt very much alone, even with the chimps so near. Once it was dark there would be no tracing my steps back to the campsite; whatever happened out here, I’d have to deal with it myself. I wedged myself between two baobab trees to feel safer.

As the afternoon wore dim, the chimps focused less on eating and more on relaxing. Beggar reclined at the base of a tree, arms behind her head and legs crossed. As soon as she was laid flat her eyes closed, as if she’d been waiting all day for this moment. Mango scrambled over her mother’s torso, slapping her head. Throughout it all, Beggar resolutely scrunched her eyes shut. Even though I was only a few yards away, neither of them paid me any attention.

Drummer, though, was a different story. At one point a stream of army ants shifted routes so that they passed near my shoe, and when I’d finished shaking my foot clear, I looked up to see the young male a few feet away, hunched over his knuckles, the hairs on the back of his neck raised. He’d stalked over soundlessly and now stared at me, the glow of the fading afternoon sun rimming his hard shiny eyes with rust. He took a step forward, his eyes locked on mine. Then he took another.

I’d confronted aggressive dogs before. I knew that you weren’t supposed to run from a violent animal. As this muscular creature crept toward me, teeth bared, all I could think was hold still, and all I could feel was get away.

I backed up, heedlessly stepping through the crust of a termite mound. I was sure the insects, plump with venom, were biting my ankles, but I couldn’t feel them. I could only stare at the beast before me. I sensed our locked gazes were only making things worse, but I couldn’t look away. Like I’d once done for Monsieur Tatagani, I had to learn as much as I could about his anger and how I might survive it.

Suddenly Drummer sprinted toward me, dragging his hands along the ground. Rocks and branches scattered before him, making a terrible noise. I sensed Beggar sitting up and heard Mango shrieking in fright even as all my thoughts turned to escape. As I leaped over a stream and into a thick stand of ferns, there was a rush of sound and a beating black wave. For a moment I thought another chimp was in front of me, that I’d been hunted and surrounded. But then it turned out to be a cluster of startled black birds, their underwings blurred arcs of white within black as they rose to the sky.

When I stumbled into the campsite I surprised Prof at his prayers; he leaped to his feet and blinked wildly while I doubled over and wheezed.

“What happened? What is it?!” he cried.

I tried to tell him, but the words wouldn’t come out right. “One . . . of those chimps . . . charged me.”

Prof nodded, suddenly calm. “I see. Is that him?”

I whirled and looked where Prof was pointing. There was Drummer, standing at the base of our hill. He steadily turned his gaze to me, then to Prof. Now that I’d run from him, his fury seemed to have drained. He was holding a hefty rock, which he hurled vaguely in our direction; it went far astray, but he still hooted triumphantly.

“Yes,” I said. “That’s him.”

“We appear,” Prof said, “to have met our neighbors.”