The Lupus Foundation of America has the estimation of the prevalence of at least 1.5 million cases. In a study of worldwide prevalence and incidence of SLE, the highest prevalence and incidence of SLE were in North America (241/100 000 and 23.2/100 000 person-years, respectively). Lower incidence of SLE was detected in Ukraine and Africa (0.3/100 000 person-years), and the lowest prevalence was reported in Northern Australia (0 cases in 847 people). Women were more commonly affected than men in every age and ethnic group. People of African ethnicity had the greatest prevalence and incidence of SLE, whereas those of the White race had the lowest prevalence and incidence. The annual incidence of SLE from the 1970s to 2000s has been estimated from approximately 1 to 10 per 100,000 population, while the SLE prevalence has been ranged from 5.8 to 130 per 100,000 population.[16]
The raccoon (/rəˈkuːn/ or US: /ræˈkuːn/ (listen), Procyon lotor), sometimes called the common raccoon to distinguish it from other species, is a mammal native to North America. It is the largest of the procyonid family, having a body length of 40 to 70 cm (16 to 28 in), and a body weight of 5 to 26 kg (11 to 57 lb). Its grayish coat mostly consists of dense underfur, which insulates it against cold weather. Three of the raccoon's most distinctive features are its extremely dexterous front paws, its facial mask, and its ringed tail, which are themes in the mythologies of the indigenous peoples of the Americas relating to the animal. The raccoon is noted for its intelligence, as studies show that it is able to remember the solution to tasks for at least three years. It is usually nocturnal and omnivorous, eating about 40% invertebrates, 33% plants, and 27% vertebrates.
D D Raccoon Race
The original habitats of the raccoon are deciduous and mixed forests, but due to their adaptability, they have extended their range to mountainous areas, coastal marshes, and urban areas, where some homeowners consider them to be pests. As a result of escapes and deliberate introductions in the mid-20th century, raccoons are now also distributed across central Europe, the Caucasus, and Japan.
In Europe, the raccoon is included since 2016 in the list of Invasive Alien Species of Union concern (the Union list).[3] This implies that this species cannot be imported, bred, transported, commercialized, or intentionally released into the environment in the whole of the European Union.[4]
Though previously thought to be generally solitary, there is now evidence that raccoons engage in sex-specific social behavior. Related females often share a common area, while unrelated males live together in groups of up to four raccoons in order to maintain their positions against foreign males during the mating season and against other potential invaders. Home range sizes vary anywhere from 3 ha (7.4 acres) for females in cities, to 5,000 ha (12,000 acres) for males in prairies. After a gestation period of about 65 days, two to five young known as "kits" are born in spring. The kits are subsequently raised by their mother until dispersal in late fall. Although captive raccoons have been known to live over 20 years, their life expectancy in the wild is only 1.8 to 3.1 years. In many areas, hunting and vehicular injury are the two most common causes of death.
Names for the species include the common raccoon,[6] North American raccoon,[7] and northern raccoon,[8] The word raccoon was adopted into English from the native Powhatan term meaning 'animal that scratches with its hands', as used in the Colony of Virginia. Its Latin name means 'before-dog washer'.[9] It was recorded on John Smith's list of Powhatan words as aroughcun, and on that of William Strachey as arathkone.[10] It has also been identified as a reflex of a Proto-Algonquian root *ahrah-koon-em, meaning '[the] one who rubs, scrubs and scratches with its hands'.[11] The word is sometimes spelled as racoon.[12]
The colloquial abbreviation coon is used in words like coonskin for fur clothing and in phrases like old coon as a self-designation of trappers.[14][15] In the 1830s, the United States Whig Party used the raccoon as an emblem, causing them to be pejoratively known as "coons" by their political opponents, who saw them as too sympathetic to African-Americans. Soon after that the term became an ethnic slur,[16] especially in use between 1880 and 1920 (see coon song), and the term is still considered offensive.[17] Dogs bred to hunt raccoons are called coonhound and coon dog.[18]
Based on fossil evidence from Russia and Bulgaria, the first known members of the family Procyonidae lived in Europe in the late Oligocene about 25 million years ago.[26] Similar tooth and skull structures suggest procyonids and weasels share a common ancestor, but molecular analysis indicates a closer relationship between raccoons and bears.[27] After the then-existing species crossed the Bering Strait at least six million years later in the early Miocene, the center of its distribution was probably in Central America.[28] Coatis (Nasua and Nasuella) and raccoons (Procyon) have been considered to share common descent from a species in the genus Paranasua present between 5.2 and 6.0 million years ago.[29] This assumption, based on morphological comparisons of fossils, conflicts with a 2006 genetic analysis which indicates raccoons are more closely related to ringtails.[30] Unlike other procyonids, such as the crab-eating raccoon (Procyon cancrivorus), the ancestors of the common raccoon left tropical and subtropical areas and migrated farther north about 2.5 million years ago, in a migration that has been confirmed by the discovery of fossils in the Great Plains dating back to the middle of the Pliocene.[31][29] Its most recent ancestor was likely Procyon rexroadensis, a large Blancan raccoon from the Rexroad Formation characterized by its narrow back teeth and large lower jaw.[32]
As of 2005, Mammal Species of the World recognizes 22 subspecies of raccoons.[33] Four of these subspecies living only on small Central American and Caribbean islands were often regarded as distinct species after their discovery. These are the Bahamian raccoon and Guadeloupe raccoon, which are very similar to each other; the Tres Marias raccoon, which is larger than average and has an angular skull; and the extinct Barbados raccoon. Studies of their morphological and genetic traits in 1999, 2003 and 2005 led all these island raccoons to be listed as subspecies of the common raccoon in Mammal Species of the World's third edition. A fifth island raccoon population, the Cozumel raccoon, which weighs only 3 to 4 kg (6.6 to 8.8 lb) and has notably small teeth, is still regarded as a separate species.[34][35][36][37]
The four smallest raccoon subspecies, with a typical weight of 1.8 to 2.7 kg (4.0 to 6.0 lb), live along the southern coast of Florida and on the adjacent islands; an example is the Ten Thousand Islands raccoon (Procyon lotor marinus).[38] Most of the other 15 subspecies differ only slightly from each other in coat color, size and other physical characteristics.[39][40] The two most widespread subspecies are the eastern raccoon (Procyon lotor lotor) and the Upper Mississippi Valley raccoon (Procyon lotor hirtus). Both share a comparatively dark coat with long hairs, but the Upper Mississippi Valley raccoon is larger than the eastern raccoon. The eastern raccoon occurs in all U.S. states and Canadian provinces to the north of South Carolina and Tennessee. The adjacent range of the Upper Mississippi Valley raccoon covers all U.S. states and Canadian provinces to the north of Louisiana, Texas and New Mexico.[41]
Head to hindquarters, raccoons measure between 40 and 70 cm (16 and 28 in), not including the bushy tail which can measure between 20 and 40 cm (7.9 and 15.7 in), but is usually not much longer than 25 cm (9.8 in).[67][68][69] The shoulder height is between 23 and 30 cm (9.1 and 11.8 in).[70] The body weight of an adult raccoon varies considerably with habitat, making the raccoon one of the most variably sized mammals. It can range from 2 to 26 kg (4.4 to 57.3 lb), but is usually between 5 and 12 kg (11 and 26 lb). The smallest specimens live in southern Florida, while those near the northern limits of the raccoon's range tend to be the largest (see Bergmann's rule).[71] Males are usually 15 to 20% heavier than females.[72] At the beginning of winter, a raccoon can weigh twice as much as in spring because of fat storage.[73][74][75] The largest recorded wild raccoon weighed 28.4 kg (63 lb) and measured 140 cm (55 in) in total length, by far the largest size recorded for a procyonid.[76][77]
The most characteristic physical feature of the raccoon is the area of black fur around the eyes, which contrasts sharply with the surrounding white face coloring. This is reminiscent of a "bandit's mask" and has thus enhanced the animal's reputation for mischief.[78][79] The slightly rounded ears are also bordered by white fur. Raccoons are assumed to recognize the facial expression and posture of other members of their species more quickly because of the conspicuous facial coloration and the alternating light and dark rings on the tail.[80][81][82] The dark mask may also reduce glare and thus enhance night vision.[81][82] On other parts of the body, the long and stiff guard hairs, which shed moisture, are usually colored in shades of gray and, to a lesser extent, brown.[83] Raccoons with a very dark coat are more common in the German population because individuals with such coloring were among those initially released to the wild.[84] The dense underfur, which accounts for almost 90% of the coat, insulates against cold weather and is composed of 2 to 3 cm (0.79 to 1.18 in) long hairs.[83]
The most important sense for the raccoon is its sense of touch.[104][105][106] The "hyper sensitive"[105] front paws are protected by a thin horny layer that becomes pliable when wet.[107][108] The five digits of the paws have no webbing between them, which is unusual for a carnivoran.[109] Almost two-thirds of the area responsible for sensory perception in the raccoon's cerebral cortex is specialized for the interpretation of tactile impulses, more than in any other studied animal.[110] They are able to identify objects before touching them with vibrissae located above their sharp, nonretractable claws.[85][106] The raccoon's paws lack an opposable thumb; thus, it does not have the agility of the hands of primates.[106][108] There is no observed negative effect on tactile perception when a raccoon stands in water below 10 C (50 F) for hours.[111] 2ff7e9595c
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