MargenWhen a gentoo penguin courts, it wanders the colony inspecting pebbles. It looks at them, discards them, compares them. In the end it picks one — smooth, round, just the right size — and lays it before the female it's wooing.
If she accepts it, the stone becomes part of the nest they'll build together: a platform of pebbles that keeps the eggs dry and safe from the meltwater.
Good stones are scarce, and in the colonies they're brazenly stolen from nest to nest: there are lookouts, quarrels and repeat thieves.
It isn't a ring, but it comes rather close: a gift chosen with care, made of a shared future.
Source: Australian Antarctic Program