Study reveals why house cats don't roar while the big cats do

Cats are a few of the creatures that often take over the Internet via their videos and also the house they live in. While the furry pawed mammals are adored for their purrs, experts have tried to explain why house cats do so instead of roaring like their jungle kins. As per a new Live Science report, the difference in vocalisations of these two classes of creatures is due to their physiology of the voice box and throat.

What causes cats to roar or purr?

According to John Wible, curator of mammals at the Carnegie Museum of Natural History in Pittsburgh, any species of cats in the Felidae family can either purr or roar as their physiology does not allow them to do both, reported the science news website. In the context of humans, the sounds cats make depends on their voice box called the larynx. Moreover, the expert explained that the sound of purring is created when a cat breathes in and out and this vocalisation first evolved in cats itself. 

Besides, Wible said that roaring evolved in a particular lineage of large cats and thus it doesn’t happen among house cats. He added that the roaring genus of cats called ‘Panthera’ includes lions, tigers, jaguars and leopards while the cats that purr include house cat, bobcat, ocelot, lynx, cougar and cheetah.

Why can’t house cats roar?

Wible explained that the vocalisation of cats totally depends on the voice box. He said that the sound of purr in cats is created after the vocalis muscle, which is in the vocal folds in the voice box, starts rapidly twitching, as per the science news website. He further said that cats who can roar have longer, heavier, stretchier, fleshier, fattier layers of tissue in their vocal chord which lacks in cats, bobcats, ocelots, lynx, cougars and cheetahs. 

How do jungle cats roar?

As per Wible, the roaring sound is created from the bendy bones in a cat’s larynx that comprises the hyoid bones and the vocal cords. One pair of hyoid apparatus, called the epihyoids, have a unique arrangement and it is an elongated elastic ligament rather than a bone. He explained that it is this flexible cartilage with which the animals can produce a  deeper-pitched sound by lowering the voice box in their throat. Although scientists don't know their role in the wild, they reportedly believe that this vocalization must have offered some evolutionary advantage in the cat ancestry. 

(Image: Pixabay)