“You just look for something out of the ordinary,” Caravaca instructs as we head toward the Caribbean.

It’s all out of the ordinary for this Canadian: walls of tropical green lining the road, wild flashes as exotic birds swoop past, not to mention monkeys swinging in trees. Costa Rica may be only a fraction of the Earth’s surface — 0.03 per cent — but nearly 6 per cent of the planet’s biodiversity is just out the car window.

Birders and biologists have been flocking here for decades, but in recent years, adorable kids’ Ice Age movies and the rest of pop culture have discovered the sloth. The unwitting superstar likes to hang out in Cecropia trees — look for leaves “shaped like hands,” Caravaca says. When he’s in the passenger seat and not navigating the video game that is Costa Rican traffic, he can spot 10 or more sloths in a couple of hours.

The locals call sloths ‘perezoso,’ for lazy bear. But they’re not really lazy. They’re just misunderstood.

“It’s not fair, guys,” says Marco Cascante, our guide at the Sloth Sanctuary in Cahuita, on the Caribbean side of the country. “This is not laziness, this is animal adaption.”

We watch a sloth climb, slo-mo, to his lunch of leaves. These energy-efficient animals have almost no body fat, take up to 50 days to digest food and only do their sloth business every week or so, slowly climbing down the tree to mark their territory.

They’re covered with thick hair to keep them warm in the Costa Rican heat, because they don’t move much and when they do “they move so slowly, they are not able to generate body heat,” Cascante says. But when sloths hear an eagle, or face another emergency, they can go as fast as you may go for a weekend run, provided you’re not on the track team.

Sloths also manage to find the energy to mate. “Motivation, right?” quips Cascante. The whole deal takes a whopping 40 seconds. (“That’s what you call a quickie,” scoffs a 60-something woman in hoop earrings next to me). Eleven months later, baby sloths are born with teeth to eat leaves and long claws to hang on to mom. But when there’s a defect and they can’t hang on, the babies fall from the trees.

“Mom hears the baby crying, but way down there,” Cascante says, adding some unexpected drama to the afternoon. “Does mama go look for baby? Yes or no?” A young woman holding her kids’ pink sippy cups shoots her hand up for ‘yes.’

“You’re right! Of course mama goes to get the baby,” says Cascante, reaffirming the world is a true and good place. “For those of you who said ‘no,’ shame on you!” he scolds.

But — more drama — even maternal bonds have their limits. If the baby keeps falling, eventually the mama sloth stops climbing down to get it.

The lucky abandoned sloths end up at the sanctuary, where they live out their days lying around in front of adoring fans. There are also plenty of ‘oohs’ and ‘ahhs’ for the sloths that have lost eyes or limbs to barbwire or power lines. But we don’t meet any of the roughly 70 per cent of the animals that are being rehabilitated to be reintroduced into the forest.

We do see a few wild sloths while paddling down a pretty stream behind the sanctuary (‘wild’ seems too frenetic an adjective). We see blue crabs scampering along the shore and crocodiles in the water, all while being serenaded by birds trilling, cicadas buzzing and howler monkeys whooping it up.

At the end of the tour, we head back to the parking lot with its giant sculpture of a sloth. Caravaca starts grinning again. He grabs the tripod, sets up the scope so I can watch a dozen or more howler monkeys climb through the trees, entirely unconcerned that their slow-moving neighbours are getting so much attention.