The piramids in Mesoamerica reflect the chirp of the quetzal birds. Clap your hands in front of the Temple of Kukulcan in Chichen Itza and the echo comes back as a chirp. The builders intentionally built the temples to do this. This spans several sites including Uxmal, Chichen Itza, and Teotihuacan to name a few.
The quetzal was sacred to the people of Mesoamerica and its image represents the Mesoamerican god Quetzalcoatl.
See the full article at National Geographic News.