Excited as the keepers were, they tempered their emotions, knowing that the cubs weren’t yet in the clear. The public showed no such restraint. The Web lit up with their exclamation-point-filled posts.

When the zoo asked participants in a Web chat how much time they spend watching the cub cam each day, 24 percent answered more than four hours. When no cubs were visible on the cam for a week between the two births, the zoo was flooded with questions about when it would go back up.

What was it about that grainy footage—in which nothing happened for long stretches—that so many people found addictive?

The cubs are cute, all fuzzy and wobbly. Scientists say our hard-wired affinity for baby-like traits is so strong, so essential to our survival, that a response is triggered in us even when we look at nonhuman species. Gazing at cute zoo babies with big eyes, button noses, and clumsy movements lights up the parts of our brains that are stimulated by other pleasures like sex and good food.

But the cub cam’s appeal is more than that; it’s a window into a scene we could never otherwise see. Even Craig Packer, an ecologist at the University of Minnesota who has spent 31 years observing lions in the Serengeti, has only rarely witnessed the early days of a cub’s life. As we watch the helpless cubs, toothless and blind, and the tender moments between mother and child, these fierce creatures don’t seem so different from us.

The cub cam gives us a new kind of intimacy with wild creatures, a glimpse—of all things—into the lion’s den.

From his favorite perch at the top of the lion yard, Luke surveys his territory. He seems a different animal from the playful adolescent who came here three years ago. Sometimes he refuses to come inside when he’s called, and he won’t tolerate Saffoe’s presence anymore; if Saffoe comes near him, he jumps up and slams his paws onto the cage door.

Luke hasn’t met his cubs yet. They’ll likely go out in the yard in late fall or early winter and will meet their father whenever their mothers decide to introduce them.

This article initially appeared in the November 2010 issue of The Washingtonian.

Motherhood has changed the sisters. They accept food from Clark and Stites, but Shera hisses and bares her teeth if the keepers come near the cubs. Once the cousins are introduced, probably by Thanksgiving, the mothers may begin to nurse one another’s cubs, as lions do in the wild.

By the time they’re two years old, the cubs will be sent to other zoos to breed and spread their valuable genes. When they’re gone, keepers will put the original trio back together and start over.

The zoo expects big crowds when the seven cubs are out in the yard. For Saffoe, Stites, and Clark, it’s been gratifying to share the process with others, to let people see what they were seeing and answer their questions. Says Clark: “It was sort of like they were experiencing this with us. Sometimes that meant being sad. But we were all watching this for the first time.”