A roar is a type of animal vocalization that is loud, deep and resonating. Many

mammal A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three ...

s have evolved to produce roars and other roar-like vocals for purposes such as long-distance communication and intimidation. These include various species of

big cat The term "big cat" is typically used to refer to any of the five living members of the genus ''Panthera'', namely the tiger, lion, jaguar, leopard, and snow leopard. All cats descend from the ''Felidae'' family, sharing similar musculature, c ...

bear Bears are carnivoran mammals of the family (biology), family Ursidae (). They are classified as caniforms, or doglike carnivorans. Although only eight species of bears are extant, they are widespread, appearing in a wide variety of habitats ...

pinniped Pinnipeds (pronounced ), commonly known as seals, are a widely range (biology), distributed and diverse clade of carnivorous, fin-footed, semiaquatic, mostly marine mammals. They comprise the extant taxon, extant families Odobenidae (whose onl ...

s, bovids,

deer A deer (: deer) or true deer is a hoofed ruminant ungulate of the family Cervidae (informally the deer family). Cervidae is divided into subfamilies Cervinae (which includes, among others, muntjac, elk (wapiti), red deer, and fallow deer) ...

elephant Elephants are the largest living land animals. Three living species are currently recognised: the African bush elephant ('' Loxodonta africana''), the African forest elephant (''L. cyclotis''), and the Asian elephant ('' Elephas maximus ...

s and

simian The simians, anthropoids, or higher primates are an infraorder (Simiiformes ) of primates containing all animals traditionally called monkeys and apes. More precisely, they consist of the parvorders New World monkey, Platyrrhini (New World mon ...

s. The anatomical basis for the ability to roar often involves modifications to the

larynx The larynx (), commonly called the voice box, is an organ (anatomy), organ in the top of the neck involved in breathing, producing sound and protecting the trachea against food aspiration. The opening of larynx into pharynx known as the laryngeal ...

and

hyoid bone The hyoid-bone (lingual-bone or tongue-bone) () is a horseshoe-shaped bone situated in the anterior midline of the neck between the chin and the thyroid-cartilage. At rest, it lies between the base of the mandible and the third cervical verte ...

and enlarged internal air spaces for low-frequency vocal resonation. While roaring, animals may stretch out their necks and elevate their heads to increase the space for resonance.

Definition

The definition of "roar" has varied between species. However Weissengruber et al. (2002) has given a more general description of roars as consisting of both a low pitch and low

formant In speech science and phonetics, a formant is the broad spectral maximum that results from an acoustic resonance of the human vocal tract. In acoustics, a formant is usually defined as a broad peak, or local maximum, in the spectrum. For harmo ...

. They have used the roars of

lion The lion (''Panthera leo'') is a large Felidae, cat of the genus ''Panthera'', native to Sub-Saharan Africa and India. It has a muscular, broad-chested body (biology), body; a short, rounded head; round ears; and a dark, hairy tuft at the ...

s and

red deer The red deer (''Cervus elaphus'') is one of the largest deer species. A male red deer is called a stag or Hart (deer), hart, and a female is called a doe or hind. The red deer inhabits most of Europe, the Caucasus Mountains region, Anatolia, Ir ...

as quintessential examples of the sound. Other researchers have mentioned similar "roar-like" vocalizations where either the pitch or formant is still higher than in true roars.

Roaring anatomy

Roaring mammals have evolved various means to achieve their vocalizations. A proportionally large

contributes to a deeper pitch. The male hammer-headed bat has a larynx that takes up most of his thoracic cavity and is half the size of his backbone. A larger larynx also has enlarged vocal cords which contributes to a deeper pitch and more massive folds leads to slower

oscillation Oscillation is the repetitive or periodic variation, typically in time, of some measure about a central value (often a point of equilibrium) or between two or more different states. Familiar examples of oscillation include a swinging pendulum ...

. In addition, the big cats (

tiger The tiger (''Panthera tigris'') is a large Felidae, cat and a member of the genus ''Panthera'' native to Asia. It has a powerful, muscular body with a large head and paws, a long tail and orange fur with black, mostly vertical stripes. It is ...

jaguar The jaguar (''Panthera onca'') is a large felidae, cat species and the only extant taxon, living member of the genus ''Panthera'' that is native to the Americas. With a body length of up to and a weight of up to , it is the biggest cat spe ...

and

leopard The leopard (''Panthera pardus'') is one of the five extant cat species in the genus ''Panthera''. It has a pale yellowish to dark golden fur with dark spots grouped in rosettes. Its body is slender and muscular reaching a length of with a ...

, referred to as the "roaring cats"), have vocal cords that are square-shaped as opposed to the triangle-shaped cords of other

felid Felidae ( ) is the Family (biology), family of mammals in the Order (biology), order Carnivora colloquially referred to as cats. A member of this family is also called a felid ( ). The 41 extant taxon, extant Felidae species exhibit the gre ...

s; this allows them to produce a louder call with less lung pressure. The elasticity of the larynx and the length of the

vocal tract The vocal tract is the cavity in human bodies and in animals where the sound produced at the sound source (larynx in mammals; syrinx in birds) is filtered. In birds, it consists of the trachea, the syrinx, the oral cavity, the upper part of t ...

affect the formant or resonance of a sound. In big cats and some male deer, specialized musculature and ligaments pull the larynx deeper in the vocal tract when roaring, lowering the vocal tract resonance. Red deer 2009

Other species have evolved internal inflatable air spaces connected to the vocal tract, which play a role in vocal resonance. The male Mongolian gazelle and musk ox possess an air space (paired and two-chambered in the former) attached to the larynx, while bears have such spaces connected to the

pharynx The pharynx (: pharynges) is the part of the throat behind the human mouth, mouth and nasal cavity, and above the esophagus and trachea (the tubes going down to the stomach and the lungs respectively). It is found in vertebrates and invertebrates ...

. Male howler monkeys have an unpaired rostroventral laryngeal air sac within the hyoid bulla (extension of the

) and a pair of ventral laryngeal air spaces outside. The hammer-headed bat has a pouch in the

palatine A palatine or palatinus (Latin; : ''palatini''; cf. derivative spellings below) is a high-level official attached to imperial or royal courts in Europe since Roman Empire, Roman times.

that connects to an enlarged

nasopharynx The pharynx (: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the esophagus and trachea (the tubes going down to the stomach and the lungs respectively). It is found in vertebrates and invertebrates, though its ...

region, in addition to paired cheek pouches which extend to the rostrum. Elephants possess a pharyngeal pouch associated with their larynx and hyoid apparatus, and their roars can also be modified by the nostrils in their trunks. Male elephant seals and saiga antelopes have an enlarged and inflated

proboscis A proboscis () is an elongated appendage from the head of an animal, either a vertebrate or an invertebrate. In invertebrates, the term usually refers to tubular arthropod mouthparts, mouthparts used for feeding and sucking. In vertebrates, a pr ...

, which also affects resonance. Saiga nevertheless roar with their mouths closed and produce a "nasal roar". The structure of the hyoid bone can play a role in an animal's ability to roar. The hyoid of the big cats is less ossified and more flexible than in other cats. The snow leopard also has this property, but cannot roar, as its shorter vocal folds provide little resistance to airflow. In howler monkeys, the hyoid bone is relatively large and cup-shaped, contributing to the depth and resonance of the call. Though usually airborne, some roars are emitted underwater, as in the case of the male harbor seal.

Biological function

In some species, roars evolved due to

sexual selection Sexual selection is a mechanism of evolution in which members of one sex mate choice, choose mates of the other sex to mating, mate with (intersexual selection), and compete with members of the same sex for access to members of the opposite sex ...

, and only one sex roars. For example, in

gorilla Gorillas are primarily herbivorous, terrestrial great apes that inhabit the tropical forests of equatorial Africa. The genus ''Gorilla'' is divided into two species: the eastern gorilla and the western gorilla, and either four or five su ...

s only the adult male (silverback) has a larynx large enough and vocal cords lengthened enough to produce a full roar. Nonetheless, in other species both sexes can produce these vocalizations. In lions, where both sexes roar, the vocalization plays a role in social spacing and territorial defense. The roars ward off other lions from mistakenly entering another lion's territory. The roar of a lion is audible for up to five miles in human hearing and probably further for lions.

In popular culture

The lion's roar is familiar to many through Leo the Lion, the iconic

logo A logo (abbreviation of logotype; ) is a graphic mark, emblem, or symbol used to aid and promote public identification and recognition. It may be of an abstract or figurative design or include the text of the name that it represents, as in ...

seen during the opening sequence of

MGM Metro-Goldwyn-Mayer Studios Inc. (also known as Metro-Goldwyn-Mayer Pictures, commonly shortened to MGM or MGM Studios) is an American Film production, film and television production and film distribution, distribution company headquartered ...

film A film, also known as a movie or motion picture, is a work of visual art that simulates experiences and otherwise communicates ideas, stories, perceptions, emotions, or atmosphere through the use of moving images that are generally, sinc ...

s. Leo's current roar, recreated by Mark Mangini in 1982 and redone in 1994 and 1995, consists of tiger growls and lion growls instead of actual roars. As Mangini later stated, "lions don't make that kind of ferocious noises ic and the logo needed to be ferocious and majestic".

References

External links

* Eklund, Robert, Gustav Peters, Gopal Ananthakrishnan & Evans Mabiza. 2011
An acoustic analysis of lion roars. I: Data collection and spectrogram and waveform analyses
In: Quarterly Progress and Status Report TMH-QPSR, Volume 51, 2011. Proceedings from Fonetik 2011. Royal Institute of Technology, Stockholm, Sweden, 8–10 June 2010, pp. 1–4. Download PDF from http://roberteklund.info. * Ananthakrishnan, Gopal, Robert Eklund, Gustav Peters, Gopal & Evans Mabiza. 2011
An acoustic analysis of lion roars. II: Vocal tract characteristics
In: Quarterly Progress and Status Report TMH-QPSR, Volume 51, 2011. Proceedings from Fonetik 2011. Royal Institute of Technology, Stockholm, Sweden, 8–10 June 2010, pp. 5–8.Download PDF from http://roberteklund.info. {{Animal communication Animal sounds Sexual selection