This is Bird Note. Listen carefully to the song of the Pacific Renn.

What we hear as a blur of sound, the Pacific Renn hears as a precise sequence of sounds.

That birds can hear so acutely the fine structure of song allows them to convey much information in a short sound.

That's probably why, Naturalist Rosemary Jealous writes, even the most extensive bird songs seem so brief to us.

Let's listen again, but this time, with the song slowed down to one quarter speed.

The Pacific Renns may hear the song of other Pacific Renns this way, enabling them to imitate each other.

The same would be true for winter Renns of the Eastern States and Eurasian Renns.

Whatever the species, they remind us that creatures we share the world with read and respond to nature in ways we sometimes cannot see or hear.