SSS 2011-09-30

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To vocalize, animals create sound waves in the pipeline² vocal¹ checks. Shorter pipes produce higher frequency sounds, so smallest animals like the cuddly³ koala should have high voices. 

 

Or not!

 

A new study suggests that male koalas developed this low mating calls to impressive females with their sizes, even there are no quite as larger as bellosports. Koala’s bearing tone is lower enough to come from a 15 centimeters pipe which should require for body larger than a bison. Instead, males developed deceptively lower voice by evolving a descended⁴ larynx which means the voice boxes sits lower than a throat. This lengthens⁵ the vocal tract⁶ which stretches between voice box and mouth, giving the koala a longer pipe and lower voice without a bigger body. The finding is in the journal of Experimental Biology. Koala calls may be misleading, but larger males are even lower voices than their runtier counterparts which allows females to identify bigger, stronger mates. To these fuzzy followers⁷ size sounds matter. 

 

Thanks for the minute for the Scientific American’s 60-sencond science. I’m Sophie Bushwick.

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