Amy Enchelmeyer
Discovery News
Thu, 09 Jun 2011 14:28 UTC

Ducklings following in a line behind a mother duck is enough to turn heads and elicit a few "awwws." But ducklings following a dog? Now that's worthy of Animal Planet's Wall of Fame where this photo first appeared.

While it might look like a strange friendship between two species, this adorable, multi-animal, fluffy overload is actually the byproduct of thousands of years of avian evolution.

"There's nothing unique here at work," according to Sara Hallager, a bird biologist at the National Zoo. "All baby birds, when they're born, the first thing they see, which is usually the same species, is what they imprint on."

When ducks or other animals imprint, it's generally on their mother. It's an instant bond from which they then learn the behavioral aspects of their species. Simply put, many baby animals are evolutionarily hardwired to follow their mother.

But sometimes, when animals are raised by humans, this imprinting can end up misplaced --on the human-- or in this case, a dog.

So how did this duckling duo end up thinking a dog was their parent? It turns out it wasn't part of the original plan when Frances Marsh, 25, and her family bought two two-day-old ducklings at a local garden center near their home in Atlantic Beach, N.C.

Yogi, the family's 5-year-old corgi, was in the car that day and was instantly fascinated by the family's purchase.

"They were in a little box. He just leaned his head over and licked them," Marsh said.

Ever since, the ducklings, Biggie and Pac (short for Tupac), have chosen to follow Yogi, as if he were their mother.

Why Yogi has returned the love may be the real mystery.

"Dogs are pretty smart, but I'm not going to try to hypothesize," said Hallanger. "But he's obviously bonded with the ducklings. It might just be part of his nature."

There's no question in Marsh's mind, though: "He thinks they're his babies."

Marsh says Yogi has been known to sleep beside the ducklings' box, herd them gently by pushing them with his nose, and once even barked to alert her that one of ducklings had gotten stuck on its back.

So what happens when the ducklings grow up?

Hallager says it's too early to tell: "As the ducks age and hormones start to kick into gear they might eventually just lose their association with the dog and become wild ducks."

But for now, at nearly two months old and losing their signature yellow baby-fluff, the trio is still inseparable and living as one big, happy, interspecies family.