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https://theconversation.com/mini-creatures-with-mighty-voices-know-their-audience-and-focus-on-a-single-frequency-192810>
"In the cloud forests of South America, amid the constant cacophony of bird and
insect noise, a deafening blare pierces through the background from time to
time. Belonging to the loudest known bird, the white bellbird,
Procnias
albus, this sound would be painful to humans listening nearby and capable of
causing immediate hearing damage from about a yard away.
Made exclusively by males serenading females, these vocalizations can reach
peak levels of more than 120 decibels on the sound pressure level scale (dB
SPL), which is equivalent to a jet aircraft taking off from 100 yards away. The
female bellbird listens some distance from the male, presumably trading off
being close enough to assess his quality as a mate without damaging her ears.
I study the hearing ability of animals and the sounds they make to communicate.
A great number of calls exist throughout the animal kingdom – and many are used
to attract mates or defend territories. Evolution has favored those able to
make sounds efficiently. The louder and more focused the energy in the call and
the closer in pitch it is to the intended listener’s optimal hearing range, the
farther away a potential mate or rival will hear it.
Many large mammals, such as singing whales, roaring lions and rumbling
elephants, produce loud low-pitched sounds that travel especially well through
most habitats. Because of their petite physical size, small animals are not
capable of making these far-reaching low-frequency sounds.
As a workaround, a number of small creatures have found ingenious ways to
deliver their messages loudly, despite their size."
Cheers,
*** Xanni ***
--
mailto:xanni@xanadu.net Andrew Pam
http://xanadu.com.au/ Chief Scientist, Xanadu
https://glasswings.com.au/ Partner, Glass Wings
https://sericyb.com.au/ Manager, Serious Cybernetics
