Gentoo penguins, Antarctica

© Nature Picture Library/Alam

Gentoo penguins, Antarctica

Gentoo penguins differ in appearance from the standard tuxedo-wearing penguins many of us imagine. Instead, they are characterised by bright-orange bills and white stripes above the eyes that extend across the tops of their heads. Their breeding and nesting habits have earned them a reputation as one of the most romantic seabirds. To signal interest in becoming a pair, gentoo penguins build intricate nests together and share pebbles as a sign of romantic interest. The nests are then used for laying eggs.

Gentoos are known for having monogynous relationships, and infidelity is often punished with excommunication from the colony. It's not uncommon for gentoo penguins to argue, like these penguins pictured in Antarctica that seem to be having a disagreement. Whether over excommunication for infidelity or jealousy over their neighbour's nesting stones, gentoos can be confrontational.