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"Pleasant" meows were shorter in
duration, with higher frequencies and tended to
descend in pitch (change from high to low notes).
"Urgent" meows were longer in duration,
with lower frequencies and ascended in pitch
(began on low notes and escalated to higher ones).
Rarely was a meow classed as both
"pleasant" and "urgent" at
once. The highly urgent calls tended to be the
least pleasant-sounding while the highly pleasant
ones were rated less urgent.
Nicastro suggests that cats may therefore have
developed different kinds of calls to "hook
into human perception tendencies" and alert
us of their mood and needs. He points out the
animals have certainly had time to adjust for
people since their domestication in Egypt over
5,000 years ago [Note: cats were domesticated
simultaneously or earlier in Pakistan]. With their
shorter life spans than people, cats have had many
more generations to evolve ways of manipulating
their owners through their calls.
This theory is flawed because in order to pass
on the meow-manipulation skills, those cats more
adept at manipulating humans would breed and those
less adept would fail to breed. The proliferation
of feral cats around the world shows that cats can
co-exist with humans very well without
manipulating people through their
"speech".
Does the ability to communicate with humans
provide a clear survival advantage so that good
communicators/manipulators survive longer and
produce more offspring than poor communicators?
Probably not since it is only relatively recently
that cats have become house-pets rather than
utilitarian animals (rodent controllers). Other
researchers admit that it is possible that cats
may have co-evolved with humans to better
communicate with people, they caution it's easy to
jump to conclusions.
Douglas Nelson, a professor of bio-acoustics at
Ohio State University reminds us that cats have
evolved different calls to communicate with each
other. The communications with humans are
modifications of the noises they use among each
other.
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