Why do lions have a loud, deep growl and house cats a high meow? It's not because of the relative size of the animals, but the relative size of their territories:
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Dr Gustav Peters and Dr Marcell Peters at the Alexander Koenig Zoological Research Museum in Bonn, Germany analysed the average frequencies of long-distance calls made by 27 different species of cat.
These included the great or "roaring" cats, such as lions, tigers and jaguars, which are able to roar due to the specialised structure of their throats.
They then looked for any relationships between the cats' calls and their size, and the habitats in which they live.
Cat species that live in more open types of habitat, such as lions, servals and cheetahs, have deeper calls.
Cats living in dense habitats, such as wildcats, clouded leopards and the little known marbled cat, communicate at a higher pitch, the researchers found.
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Improper conclusion. Perhaps larger animals need larger territories because they eat more and have the means to control a larger territory? And perhaps larger lung capacities among similar animals means that the larger ones make deeper sounds?
Higher pitched calls carry farther in the brush than lower calls, so animals and birds that live in shrubby habitat (and in the treetops) have higher calls to penetrate the all the leaves.
While, in general, lower calls are associated with larger animals, lower calls would be completely lost in dense undergrowth.