Jaguar
The jaguar is a large cat species and the only living member of the genus Panthera that is native to the Americas. Its distinctively marked coat features pale yellow to tan colored fur covered by spots that transition to rosettes on the sides, although a melanistic black coat appears in some individuals. With a body length of up to and a weight of up to, it is the biggest cat species in the Americas and the third largest in the world. The jaguar's powerful bite allows it to pierce the carapaces of turtles and tortoises, and to employ an unusual killing method: it bites directly through the skull of mammalian prey between the ears to deliver a fatal blow to the brain.
The modern jaguar's ancestors probably entered the Americas from Eurasia during the Early Pleistocene via the land bridge that once spanned the Bering Strait. The oldest jaguar fossils found in North America date to between. Today, the jaguar's range extends from the Southwestern United States across Mexico and much of Central America, the Amazon rainforest and south to Paraguay and northern Argentina. It inhabits a variety of forested and open terrains, but its preferred habitat is tropical and subtropical moist broadleaf forest, wetlands and wooded regions. It is adept at swimming and is largely a solitary, opportunistic, stalk-and-ambush apex predator. As a keystone species, it plays an important role in stabilizing ecosystems and in regulating prey populations.
The jaguar is threatened by habitat loss, habitat fragmentation, poaching for trade with its body parts and killings in human–wildlife conflict situations, particularly with ranchers in Central and South America. It has been listed as Near Threatened on the IUCN Red List since 2002. The wild population is thought to have declined since the late 1990s. Priority areas for jaguar conservation comprise 51 large areas inhabited by at least 50 breeding individuals, called Jaguar Conservation Units. They are located in 36 geographic regions from Mexico to Argentina.
The jaguar has featured prominently in the mythology of indigenous peoples of the Americas, including those of the Aztec and Maya civilizations.
Etymology
The word "jaguar" is possibly derived from the Tupi-Guarani word yaguara meaning 'wild beast that overcomes its prey at a bound'. Because jaguar also applies to other animals, indigenous peoples in Guyana call it jaguareté, with the added sufix eté, meaning "true beast"."Onca" is derived from the Portuguese name onça for a spotted cat that is larger than a lynx; cf. ounce. The word "panther" is derived from classical Latin panthēra, itself from the ancient Greek πάνθηρ.
In North America, the word is pronounced with two syllables, as, while in British English, it is pronounced with three, as.
Taxonomy and evolution
Taxonomy
In 1758, Carl Linnaeus described the jaguar in his work Systema Naturae and gave it the scientific name Felis onca.In the 19th and 20th centuries, several jaguar type specimens formed the basis for descriptions of subspecies. In 1939, Reginald Innes Pocock recognized eight subspecies based on the geographic origins and skull morphology of these specimens.
Pocock did not have access to sufficient zoological specimens to critically evaluate their subspecific status but expressed doubt about the status of several. Later consideration of his work suggested only three subspecies should be recognized. The description of P. o. palustris was based on a fossil skull.
By 2005, nine subspecies were considered to be valid taxa:
- P. o. onca was a jaguar from Brazil.
- P. o. peruviana was a jaguar skull from Peru.
- P. o. hernandesii was a jaguar from Mazatlán in Mexico.
- P. o. palustris was a fossil jaguar mandible excavated in the Sierras Pampeanas of Córdova District, Argentina.
- P. o. centralis was a skull of a male jaguar from Talamanca, Costa Rica.
- P. o. goldmani was a jaguar skin from Yohatlan in Campeche, Mexico.
- P. o. paraguensis was a skull of a male jaguar from Paraguay.
- P. o. arizonensis was a skin and skull of a male jaguar from the vicinity of Cibecue, Arizona.
- P. o. veraecrucis was a skull of a male jaguar from San Andrés Tuxtla in Mexico.
Evolution
The Panthera lineage is estimated to have genetically diverged from the common ancestor of the Felidae around to. Some genetic analyses place the jaguar as a sister species to the lion with which it diverged, but other studies place the lion closer to the leopard.The lineage of the jaguar appears to have originated in Africa and spread to Eurasia 1.95–1.77 mya. The living jaguar species is often suggested to have descended from the Eurasian Panthera gombaszogensis. The ancestor of the jaguar entered the American continent via Beringia, the land bridge that once spanned the Bering Strait, Some authors have disputed the close relationship between P. gombaszogensis and the modern jaguar. The oldest fossils of modern jaguars have been found in North America dating between 850,000-820,000 years ago. Results of mitochondrial DNA analysis of 37 jaguars indicate that current populations evolved between 510,000 and 280,000 years ago in northern South America and subsequently recolonized North and Central America after the extinction of jaguars there during the Late Pleistocene.
Two extinct subspecies of jaguar are recognized in the fossil record: the North American P. o. augusta and South American P. o. mesembrina.
Description
The jaguar is a compact and muscular animal. It is the largest cat native to the Americas and the third largest in the world, exceeded in size only by the tiger and the lion. It stands tall at the shoulders.Its size and weight vary considerably depending on sex and region: weights in most regions are normally in the range of. Exceptionally big males have been recorded to weigh as much as.
The smallest females from Middle America weigh about. It is sexually dimorphic, with females typically being 10–20% smaller than males. The length from the nose to the base of the tail varies from. The tail is long and the shortest of any big cat.
Its muscular legs are shorter than the legs of other Panthera species with similar body weight.
Size tends to increase from north to south. Jaguars in the Chamela-Cuixmala Biosphere Reserve on the Pacific coast of central Mexico weighed around.
Jaguars in Venezuela and Brazil are much larger, with average weights of about in males and of about in females.
The jaguar's coat ranges from pale yellow to tan or reddish-yellow, with a whitish underside and covered in black spots. The spots and their shapes vary: on the sides, they become rosettes which may include one or several dots. The spots on the head and neck are generally solid, as are those on the tail where they may merge to form bands near the end and create a black tip. They are elongated on the middle of the back, often connecting to create a median stripe, and blotchy on the belly. These patterns serve as camouflage in areas with dense vegetation and patchy shadows.
Jaguars living in forests are often darker and considerably smaller than those living in open areas, possibly due to the smaller numbers of large, herbivorous prey in forest areas.
The jaguar closely resembles the leopard but is generally more robust, with stockier limbs and a more square head. The rosettes on a jaguar's coat are larger, darker, fewer in number and have thicker lines, with a small spot in the middle.
It has powerful jaws with the third-highest bite force of all felids, after the tiger and the lion.
It has an average bite force at the canine tip of 887.0 Newton and a bite force quotient at the canine tip of 118.6.
A jaguar can bite with a force of with the canine teeth and at the carnassial notch.
Color variation
jaguars are also known as black panthers. The black morph is less common than the spotted one.Black jaguars have been documented in Central and South America. Melanism in the jaguar is caused by deletions in the melanocortin 1 receptor gene and inherited through a dominant allele. Black jaguars occur at higher densities in tropical rainforest and are more active during the daytime. This suggests that melanism provides camouflage in dense vegetation with high illumination.
In 2004, a camera trap in the Sierra Madre Occidental mountains photographed the first documented black jaguar in Northern Mexico. Black jaguars were also photographed in Costa Rica's Alberto Manuel Brenes Biological Reserve, in the mountains of the Cordillera de Talamanca, in Barbilla National Park and in eastern Panama.
Distribution and habitat
In 1999, the jaguar's historic range at the turn of the 20th century was estimated at, stretching from the southern United States through Central America to southern Argentina. By the turn of the 21st century, its global range had decreased to about, with most declines occurring in the southern United States, northern Mexico, northern Brazil, and southern Argentina.Its present range extends from the United States, Mexico, through Central America to South America comprising Belize, Guatemala, Honduras, Nicaragua, Costa Rica, particularly on the Osa Peninsula, Panama, Colombia, Venezuela, Guyana, Suriname, French Guiana, Ecuador, Peru, Bolivia, Brazil, Paraguay and Argentina. It is considered to be locally extinct in El Salvador and Uruguay.
Jaguars have been occasionally sighted in Arizona, New Mexico and Texas, with 62 accounts reported in the 20th century.
Between 2012 and 2015, a male vagrant jaguar was recorded in 23 locations in the Santa Rita Mountains. Eight jaguars were photographed in the southwestern US between 1996 and 2024.
The jaguar prefers dense forest and typically inhabits dry deciduous forests, tropical and subtropical moist broadleaf forests, rainforests and cloud forests in Central and South America; open, seasonally flooded wetlands, dry grassland and historically also oak forests in the United States. It has been recorded at elevations up to but avoids montane forests. It favors riverine habitat and swamps with dense vegetation cover. In the Mayan forests of Mexico and Guatemala, 11 GPS-collared jaguars preferred undisturbed dense habitat away from roads; females avoided even areas with low levels of human activity, whereas males appeared less disturbed by human population density. A young male jaguar was also recorded in the semi-arid Sierra de San Carlos at a waterhole.