Valentine's Day: Romantic secrets of the animal kingdom

Zoos in Cologne, Nuremberg, Hanover and Krefeld are offering walking tours that will look at the unique romantic habits of some of the most popular animals exhibited. Lions, for instance, can mate up to 50 times in one day. Now that’s stamina!

In an interview with German news agency DPA, Nuremberg Zoo educator Christian Dienemann said penguins were especially loyal lovers. "They usually spend a long time with their partners," he said, "if not always for their entire lives."

During courtship, flamingos, who judge a potential partner's worth by the feel of his or her body, perform acrobatic rituals with each other. "You could say they dance," Dienemann said.

Pygmy marmoset females, who are usually no bigger than a human fist, often give birth to twins. For that reason, according to Dienemann, fathers tend to take on some of the burden of caring for the children.

Always the largest in her school, the female clown fish travels around with a "harem" of males. The males also have the ability to transform themselves into females - solving the difficulty of never being able to find a mate.

A female red-billed hornbill has an especially unique test for her potential mates: She makes them feed her. Only once a male hornbill has proven his skills does he pass the test.

Dienemann said he hoped patrons would learn something from the zoo tours. "We want to explain something about the biological background of the relationships," he said. "It shouldn't be silly, but it shouldn't be too serious, either. Rather, it should be tongue-in-cheek."