I am told there may be jaguars in this jungle and I'm keeping an eye out.
This is Panama, the capital of summer hats and slow-moving air. We explorers are trying to keep feet out of mud, mighty ant mounds and trap-like knots of vines. We get buzz-bombed by flies, and at one point, walk right smack into a shower that sends down not just drops of rain, but tropical nuts and sharp chips of bark.
Thanks to a bus ride, and to our guide, Wilberto Ordonez, we are marching around in here instead of sitting on the deck of our cruise ship. Staring up at cashew trees and giant philodendrons instead of watching the water rise and fall as we ease into the Caribbean edge of the Panama Canal.
Our shore excursion is due to end back at the dock by 5 p.m. sharp and I keep whisking mosquitoes off my watch, wondering how it will be possible to get back there in time. There are so many leaf fans overhead, so many wilting flowers, that it feels like evening already, no matter where we walk.
Maybe it is the filtered light, but for the first part of our tour, nothing appears alive. This gray rock, Wilberto tells us, is a sleeping iguana.
I am eager to believe.
That silvery object, perched on a bush, is a type of butterfly. It would be a better butterfly, I think, if it would spread its wings.
Wilberto wants us to see wildlife. A rainforest full to the brim. But I am holding out for something that moves.
Suddenly, Wilberto sticks up a thick hand. He is pointing up a tree, and for a second I think it is another one of those sights that are invisible except to guides. But then I see it: a hairy foot, or something, hanging upside-down from a branch.
There is more. A chest and a drowsy head, and Wilberto outlines its shape for us so we can see how it hangs. The shape of a three-toed sloth.
We are glad to see him, and the second someone in our group snaps a picture, the sloth begins to move. His muscles work deliberately, as if he runs on batteries that are losing power. Tensely, like a performer in the Cirque de Soleil, the sloth changes his branch. Wilberto makes sure we have all taken this in, and grins.
"He do not come down to defecate!" notes Wilberto. "Maybe one time a week, on Saturday, he do it. But he do not come down."
That sounds fair enough to me. But, though this is only Wednesday, no one is quite sure whether we ought to stand back out of the way. Give the sloth more room.
Suddenly, as the animal arches his back, it is as if someone has set off a stampede. We all scramble at once, tripping backward, tearing our TravelSmart and L.L. Bean khakis against a clump of thorns.
One man falls down into the thorn bush and because it happens so fast, he does not let out a yell. But we can see his yellow vest inside a network of spooled-up branches and spikes shiny as wire.
For a second no one says a word. This is a puzzle for experts, and it will take a person who is very smart to solve it. We are circling the plant, looking to see if there is a way in.
Wilberto reaches for something, and I can see a glint of steel as it is hoisted into the air.
"No, wait!" someone yells, but it is no use. There is a chuff, chuff, chuff as Wilberto hacks and chops, working like a talented chef, slicing and mincing, but never catching the turned-up feet and legs of our group member.
The chopping does not take long, but it is hard work for four of us to drag the man out and prop him up on some tree roots to take a look. He is itching and scratching, but all we can find are small scrapes on both wrists and on the back of his neck. Wilberto seems pleased.
"OK," he says, and soon we are walking again, moving much more carefully now in case there are hidden thorns. Wilberto points out a plant that he tells us is "very poisonous" and one tree that he makes us stop at to tear off a small piece of bark.
"Try it!" he suggests to a woman in the group. "Go on and try it!"
Before she can decide, Wilberto nibbles it himself and breaks into a delighted smile. "It tastes like Pepto Bismol!" he announces triumphantly, and now everyone crowds around, curious for a taste. Wilberto is right.
And as we trudge away, I secretly strip off another piece for later, to take back to the ship.
The sun, when we can see it, is starting to go orange now, and our path is even more shadowy and tricky. Wilberto does not put his machete back in its sheath, but slices away a branch here and there to show us what he calls a "shrimp plant," tinged with pink and red, and some sour ginger that he cuts up into nuggets and puts away into his bag.
We approach a tropical anthill, and Wilberto calls us to gather around. This time his gaze lands on a girl, 11 or 12 years old. "Stick your finger in there!" he commands.
"Stick your finger in!" he repeats. "It hot!"
Again, curiosity wins out, and not only the girl but all of us are sliding our pinkies into what Wilberto tells us is a compost pile constructed by cutter ants. "Nice," says one man. "It feels nice."
When we stop for a rest, Wilberto refuses to sit and instead works on hacking at a gigantic palm frond. Holding the machete in one hand, and passing it back and forth like a wand, Wilberto the Magnificent gives the palm a shake.
Just like that, he is holding not a branch, but a dangling mop of fibers. We applaud.
"Do you know what I am showing you?" he asks, and nobody's guess is right. "This is how you make the thing that Panama is famous for!"
Although we are thinking "Canal" Wilberto shouts out, "Hat!"
I am wondering how you weave a head-covering out of this mess, but members of the group have moved ahead, and all of a sudden there is excitement. Even Wilberto runs to see what it is, and when I get there, I can see it, too: wiry figures scampering around in the highest branches of a very tall tree.
"Howler monkeys!" says Wilberto, wide-eyed. "Look at the tails!"
We are snapping pictures again, amazed that we are seeing these outside of a zoo. Mostly they watch us, as we watch them. When we stash our cameras and get back on the path, Wilberto lets out a sigh. "They are very peaceful monkeys," he explains. "Nobody likes them as pets because they lazy. Sleep all day."
Something about seeing the monkeys makes us walk more quietly. Maybe it is the fact that every monkey stopped what he was doing to peer down at us. We are whispering now, and I have the sense that it is us--and not the jungle--that is on display.
As in old cartoons, I start to imagine pairs of eyes peeking out of the leaves on both sides of the path. I tell no one, but I am picking up the sound of something crunching just to the side of us. It stops whenever we stop. And it crunches again the second we begin to move.
Just when I am about to alert Wilberto, it happens. We hear a roar.
Everyone has stopped, and we are listening for more. Jaguar! I think. And despite my eagerness to see one, things have changed.
There isn't a bone in my body that doesn't wish this animal away. Not a muscle that doesn't tense for retreat, doesn't plan to slip behind Wilberto and his sharp machete. But the crunching is steady now, and there is a sound of puffing, and then a low, dark growl.
The jaguar, which must be a dominant male, is padding steadily towards us around a bend on the path.
We grab elbows, we sweat, we crouch low.
There is a gasp. Something black and yellow has sprung out of the bush into full view.
It is our bus.
With its final crunching of gears and a breath of air brakes, the coach has wheeled off the road and onto the end of our path. The driver has popped open the door.
Some of us are loading our gear now. Some of us are shaking hands with Wilberto, selecting chunks of sour ginger from his knapsack.
And some of us are wiping our brow.
Peter Mandel is an author of picture books for kids, including his read-aloud bestseller: Jackhammer Sam (Macmillan/Roaring Brook), and his newest about zoo animals passing on a very noisy sneeze: Zoo Ah-Choooo (Holiday House).