So do the birds experience emotions at all? "Zoologists would say, Probably not," said Kooyman, who works for the Scripps Institution of Oceanography. "A lot of what looks to us like love or grief is probably hormonally driven more than some kind of attachment" to the egg, chick, or partner, he said.
For instance, there are several scenes in the film when a parent seems to grieve over a broken egg doomed never to hatch, or appears to mourn over the body of its frozen chick.
"The adult would not recognize the chick after it's frozen," Kooyman said. "The main recognition between the adults and chick is the call. If a chick can't call back, the adult won't pay any attention to it."
Instinct, hormones, and the drive to reproduce influence a lot of the penguin behavior, Kooyman said.
"What gives the impression sometimes of sorrow is that they fool around with the [broken or frozen] egg, or other birds try to take an egg away," Kooyman said. "There's just a drive to incubate, to participate in breeding behavior at that time of year for these birds."
The film also shows multiple shots of two adult penguins cuddling side by side, their beaks touching and forming almost a heart shape. It looks like love, but is it?
Despite the beautiful imagery, it's not certain that each posturing pair is actually a mated pair.
"If it's in August or September, the two are probably mates," Kooyman said. "In April it could easily be two birds that get together and then decide that they wouldn't make good partners.
"You also see such posturing at the ice's edge. There's a lot of social behavior between adults," he added.
Unlike nesting birds, penguin parents actually spend very little time together.
The penguins make the grueling journey across some 70 miles (110 kilometers) of Antarctic ice each April to return to the breeding grounds where they were born. After the courtship period, the couple forms a strong bond until the egg is laid in May or early June.
However, as soon as the egg is transferred to the father, the mother takes off to return to her feeding grounds. She returns some two months later. The starving male, who hasn't had a meal in months, immediately leaves.
The two trade off rearing their fish and returning to the sea to feed for about five months, until the chick is old enough to be left on its own. After that point the parents will probably never see each otheror their offspringagain.
"In a way, the film anthropomorphized the lives of the penguins, but I think it's OK," Kooyman said. "Simplifying some aspects of the penguins' life story makes it more accessible to the general public."
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