"Nico Declercq of Ghent University and his colleagues have shown how sound waves ricocheting around the tiered steps of the El Castillo pyramid, at the Mayan ruin of Chichén Itzá near Cancún in Mexico, create sounds that mimic the chirp of a bird and the patter of raindrops." Neat.

But not everyone is convinced. For one, there's really no way for us to know if the Mayans had a way to predict what the accoustics would sound like once the pyramids were finished, much less figure out which particular sound they were after in the first place. Also (though this isn't in the article) it's a lot of work for not much payoff. So we should probably stick with the UFO landing pad hypothesis for now.

I'll do some research on my cruise and I'll get back to you.