Maybe it's their endearing waddle. Maybe it's their seemingly analytical gaze. Or maybe it's their absurd, tuxedolike formality.
Whatever the explanation, there's no denying that penguins are one of the most intriguing, enchanting species on earth.
"They're comical, they're endearing and this is a spectacle of nature," Dee Boersma, one of the world's leading penguin experts, said as she sat recently on an Argentine beach surrounded by thousands of penguins. "You don't see many spectacles like this anywhere in the world."
The spectacular Punta Tombo Peninsula in Argentina's Patagonia region is home this time of year to half-a-million Magellanic penguins, the largest colony of these 2½-feet-tall penguins in the world.
For pictures of the Punta Tombo penguins, click HERE.
The area is also home to Boersma this time of year. The University of Washington biologist has been coming here for almost 30 years to conduct one of the longest-continual studies of penguins anywhere.
She has banded more than 60,000 penguins in her three decades here.
"OK," she said as she walked along the beach, counting penguins with a clicker in her palm, "so I just looked at 152 birds and one of them's got a band."
Boersma has tracked generations of penguins and documented an alarming decline in the penguin population here.
"I mean that when penguins aren't doing well, they're telling us that our world isn't doing well," she said.
Boersma is one of the world's leading experts on the quirky creatures. In the process, she has also become an expert on penguin romance. She even offers a play-by-play of the penguin mating ritual.
"He's courting, he's trying to get this female to pay attention to him," she said with a grin, watching an awkward male try to get the attention of an indifferent female.
Penguin fidelity patterns are remarkably evocative of another species, one we know quite well, Boersma said.
"We 've had some pairs that have stayed together for 16 years, so that's really high fidelity," she said. "They're monogamous, but they're not necessarily faithful, particularly if they fail to raise their eggs or their chicks. Then they're much more likely to divorce in the next year."
By late afternoon, strange sounds punctured the air. It sounded like a donkey but it's penguins, just returned from a fishing expedition. It's no accident that early settlers called them jackass penguins.
"That noise that you're hearing, a couple has just come back, so one of the pair was gone, and they've just returned," Boersma explained, with a mischievous grin. "So that's the greeting. 'Hi honey, I'm home.'"
The penguins, which have been out fishing, come in for a landing at the water's edge.
As the sun starts to set -- very late in the day this far south at this time of year -- the beaches of Punta Tombo fill with wet, weary penguins.
The penguins are arriving, but it's hard to tell whether they're just playing around in the surf or coming from somewhere. "They're coming back to feed their chicks," the noted penguiphile said. "They've been gone for several days, and they're coming back so fat because they've got to bring back fish to be able to feed their two chicks."
They fill their bellies with fish and then they regurgitate it.
"So, basically, the parents are the refrigerators and they come back storing the fish inside and then they regurgitate to the chicks and that's how they grow," Boersma said.