Category Archives: LIVES

HEARING CONTEST

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waxmothThe bat is the king of extreme hearing in the mammalian world. It uses echolocation, emitting ultrasonic sounds and measuring the length of time before the sounds echo back, in order to locate prey. But it turns out there’s an animal that uses an even more extreme variety of sounds.

Ultrasound simply refers to a sound that is outside a human’s sonic range–which isn’t that hard, really, as humans have modest auditory abilities. Researchers discovered that the greater wax moth (Galleria mellonella), a dull-colored, generally boring and common moth, has the most extreme hearing sense of any known animal. It’s capable of hearing sounds frequencies of up to 300,000 Hz !

frequency-hearing-range-in-man-and-some-common-animalHuman ear frequencies ranging between 20 Hz (lowest pich) and 20,000 Hz (highest pitch). Below 20 Hz (infrasounds), some species as the mole or the elephant are still hearing (they can for instance hear some vibrations from earthquakes). Similarly, lot of mammalian species can hear over 20,000 Hz (ultrasounds). Thus, cats and dogs hear up to 40,000 Hz, and dolphins or bats hear up to 160,000 Hz.  The video below demonstrates the human spectrum of hearing.

Here is a comparative chart of hearing for various animals.  Porpoises and whales and bats have the most sensitive hearing among mammals.

Species Approximate Range (Hz) 
human 64-23,000
dog 67-45,000
cat 45-64,000
cow 23-35,000
horse 55-33,500
sheep 100-30,000
rabbit 360-42,000
rat 200-76,000
mouse 1,000-91,000
gerbil 100-60,000
guinea pig 54-50,000
hedgehog 250-45,000
raccoon 100-40,000
ferret 16-44,000
opossum 500-64,000
chinchilla 90-22,800
bat 2,000-110,000
beluga whale 1,000-123,000
elephant 16-12,000
porpoise 75-150,000
goldfish 20-3,000
catfish 50-4,000
tuna 50-1,100
bullfrog 100-3,000
tree frog 50-4,000
canary 250-8,000
parakeet 200-8,500
cockatiel 250-8,000
owl 200-12,000
chicken 125-2,000

PIANO BLUES DOCUMENTARY FILM

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Blues is THE authentic American music art form.  It is the genesis on rock and roll, jazz and many other modern musical forms.  This filmed documentary was produced by Martin Scorcese, and hosted by Clint Eastwood.  It features interviews and performances by all of the great piano blues artists, including Ray Charles.  This is a true classic (with Spanish subtitles)