Throughout the park the Apenheul tries to underscore the similarities between humans and primates. Beyond the usual information about evolution, with skulls and skeletons making the physical argument for the relationships between our species, a series of playgrounds challenged young visitors to climb, crawl, walk and move like their primate cousins. A climbing wall near the Berber monkeys and a swinging rope near the orangutan exhibit were especially popular with our daughters.
So, too, were the presence of many baby primates. On our visit, during our daughters' spring break vacations, the springtime effect was in full force. At the orangutan exhibit, a baby clung to its mother's fur as she climbed in and out between the indoor and outdoor play areas.
At the pygmy marmoset space, a baby no bigger than my pinkie finger perched on a grown marmoset's shoulder. The baby had been born less than two weeks before our visit, and as it huddled with three other marmosets under a heat lamp, I could only think of my own little family of four.
Five baby gorillas, four female and one male, had been born at the Apenheul in the previous year, a record for a zoo its size. And though the park's gorillas spend much of the year on a small "island" at a distance from the other primates and visitors, they were still inside "Gorillas innen," a special gorilla house where we could see the babies and their mothers up close.
We were instantly charmed. Save for their size and strength, the baby gorillas seemed to act like typical toddlers, banging their fists for food, enjoying games of tag and cuddling up to their mothers for hugs.
One baby gorilla in particular caught our older daughter's eye. She patiently waited for other guests to clear the area and then put her hand up against the plexiglass in a sign of greeting.
She, and we, were floored by what came next: The young gorilla peered at our daughter for a moment and then placed its hand against the glass on the opposite side, mimicking our daughter's greeting.
Our daughter turned to us, tears in her eyes, visibly moved. "I'll never forget this," she said.
Nor would we.