This morning the air was foggy and the streets were soggy. I knew about the fog Thursday morning even before I rolled out of bed. A fog horn that must be close by on the coast sounded a few times in the night. Fog horns emit sounds at around 50 Hz, and humans can hear sounds between 20 Hz and at most 20 kHz. (Check out the cool animated picture of a sound wave that I found on line). And my research also found that blue whales can hear sounds as low as 5 Hz, while on the opposite end there is the Jamaican fruit bat, that can pick up ultrasound squeaks pitched at 130 kHz. Whoah Mr Bat! What fine ears you have!
