Foxes are small-to-medium-sized omnivorous belonging to several genera of the family Canidae. They have a flattened skull; upright, triangular ears; a pointed, slightly upturned snout; and a long, bushy tail ("brush").
Twelve species belong to the monophyly "true fox" group of genus Vulpes. Another 25 current or extinction species are sometimes called foxes – they are part of the paraphyly group of the South American foxes or an outlying group, which consists of the bat-eared fox, gray fox, and island fox.
Foxes live on every continent except Antarctica. The most common and widespread species of fox is the red fox ( Vulpes vulpes) with about 47 recognized subspecies. The global distribution of foxes, together with their widespread reputation for cunning, has contributed to their prominence in popular culture and folklore in many societies around the world. The Fox hunting with packs of hounds, long an established pursuit in Europe, especially in the British Isles, was exported by European settlers to various parts of the New World.
Etymology
The word
fox comes from Old English and derives from
Proto-Germanic *
fuhsaz. This in turn derives from Proto-Indo-European *
puḱ- "thick-haired, tail." Male foxes are known as
dogs,
tods, or
; females as
vixens; and young as
cubs,
pups, or
kits, though the last term is not to be confused with the
kit fox, a distinct species. "Vixen" is one of very few
modern English words that retain the
Middle English southern dialectal "v" pronunciation instead of "f"; i.e., northern English "fox" versus southern English "vox".
A group of foxes is referred to as a
skulk,
leash, or
earth.
Phylogenetic relationships
Within the Canidae, the results of
DNA analysis shows several
Phylogenetics divisions:
-
The Vulpini, which include the kit fox ( Vulpes velox), red fox ( Vulpes vulpes), Cape fox ( Vulpes chama), Arctic fox ( Vulpes lagopus), fennec fox ( Vulpes zerda), and bat-eared fox ( Otocyon megalotis) .
-
The wolf-like canids, (genus Canis, Cuon and Lycaon) including the dog (Canis lupus familiaris), gray wolf ( Canis lupus), red wolf ( Canis rufus), eastern wolf ( Canis lycaon), coyote ( Canis latrans), golden jackal ( Canis aureus), Ethiopian wolf ( Canis simensis), black-backed jackal ( Canis mesomelas), side-striped jackal ( Canis adustus), dhole ( Cuon alpinus), and African wild dog ( Lycaon pictus).
-
The South American canids, including the bush dog ( Speothos venaticus), hoary fox ( Lycalopex uetulus), crab-eating fox ( Cerdocyon thous) and maned wolf ( Chrysocyon brachyurus).
-
Various monotypic taxon, including the gray fox ( Urocyon cinereoargenteus).
Biology
General morphology
Foxes are generally smaller than some other members of the family
Canidae such as
Gray wolf and
, while they may be larger than some within the family, such as
. In the largest species, the
red fox, males weigh between ,
while the smallest species, the
fennec fox, weighs just .
Fox features typically include a triangular face, pointed ears, an elongated rostrum, and a bushy tail. They are digitigrade (meaning they walk on their toes). Unlike most members of the family Canidae, foxes have partially retractable . Fox vibrissae, or whiskers, are black. The whiskers on the muzzle, known as mystacial vibrissae, average long, while the whiskers everywhere else on the head average to be shorter in length. Whiskers (carpal vibrissae) are also on the forelimbs and average long, pointing downward and backward. Other physical characteristics vary according to habitat and adaptive significance.
Pelage
Fox species differ in fur color, length, and density. Coat colors range from pearly white to black-and-white to black flecked with white or grey on the underside.
(and other species of fox adapted to life in the desert, such as
), for example, have large ears and short fur to aid in keeping the body cool.
, on the other hand, have tiny ears and short limbs as well as thick, insulating fur, which aid in keeping the body warm.
, by contrast, have a typical
auburn hair fur, the tail normally ending with a white marking.
A fox's coat color and texture may vary due to the change in seasons; fox pelts are richer and denser in the colder months and lighter in the warmer months. To get rid of the dense winter coat, foxes moult once a year around April; the process begins from the feet, up the legs, and then along the back. Coat color may also change as the individual ages.
Dentition
A fox's
dentition, like all other canids, is I 3/3, C 1/1, PM 4/4, M 3/2 = 42. (Bat-eared foxes have six extra molars, totalling in 48 teeth.) Foxes have pronounced
carnassial pairs, which is characteristic of a
carnivore. These pairs consist of the upper premolar and the lower first molar, and work together to shear tough material like flesh. Foxes' canines are pronounced, also characteristic of a carnivore, and are excellent in gripping prey.
Behaviour
In the wild, the typical lifespan of a fox is one to three years, although individuals may live up to ten years. Unlike many canids, foxes are not always pack animals. Typically, they live in small family groups, but some (such as
) are known to be solitary.
Foxes are . Their diet is made up primarily of such as insects and small such as reptiles and birds. They may also eat eggs and vegetation. Many species are generalist predators, but some (such as the crab-eating fox) have more specialized diets. Most species of fox consume around of food every day. Foxes cache excess food, burying it for later consumption, usually under leaves, snow, or soil. While hunting, foxes tend to use a particular pouncing technique, such that they crouch down to camouflage themselves in the terrain and then use their hind legs to leap up with great force and land on top of their chosen prey. Using their pronounced canine teeth, they can then grip the prey's neck and shake it until it is dead or can be readily disemboweled.
The gray fox is one of only two canine species known to regularly climb trees; the other is the raccoon dog.
Sexual characteristics
The male fox's
scrotum is held up close to the body with the
testes inside even after they descend. Like other canines, the male fox has a
baculum, or penile bone.
[Čanády, Alexander. "Variability of the baculum in the red fox (Vulpes vulpes) from Slovakia." Zoology and Ecology 23.3 (2013): 165–170.][Bijlsma, Rob G. " Copulatory lock of wild red fox (Vulpes vulpes) in broad daylight. " Naturalist 80: 45–67.] The testes of
are smaller than those of Arctic foxes.
Spermatogenesis in red foxes begins in August–September, with the testicles attaining their greatest weight in December–February.
Vixens are in heat for one to six days, making their reproductive cycle twelve months long. As with other canines, the Egg cell are shed during estrus without the need for the stimulation of copulating. Once the egg is fertilized, the vixen enters a period of gestation that can last from 52 to 53 days. Foxes tend to have an average litter size of four to five with an 80 percent success rate in becoming pregnant. Litter sizes can vary greatly according to species and environmentthe Arctic fox, for example, can have up to eleven kits.
The vixen usually has six or eight mammae. Each teat has 8 to 20 , which connect the mammary gland to the nipple, allowing for milk to be carried to the nipple.
Vocalization
The fox's vocal repertoire is vast, and includes:
- Whine
- Made shortly after birth. Occurs at a high rate when kits are hungry and when their body temperatures are low. Whining stimulates the mother to care for her young; it also has been known to stimulate the male fox into caring for his mate and kits.
- Yelp
- Made about 19 days later. The kits' whining turns into infantile barks, yelps, which occur heavily during play.
- Explosive call
- At the age of about one month, the kits can emit an explosive call which is intended to be threatening to intruders or other cubs; a high-pitched howl.
- Combative call
- In adults, the explosive call becomes an open-mouthed combative call during any conflict; a sharper bark.
- Growl
- An adult fox's indication to their kits to feed or head to the adult's location.
- Bark
- Adult foxes warn against intruders and in defense by barking.
In the case of domesticated foxes, the whining seems to remain in adult individuals as a sign of excitement and submission in the presence of their owners.
Classification
Canids commonly known as foxes include the following genera and species:
|
|
, native to the Ethiopian highlands]] |
, a South American species]] |
Illustration by John Gerrard Keulemans (1842–1912)]] |
| in Departamento de Flores, Uruguay]]
|
in Kenya]] |
| ( Urocyon cinereoargenteus), in Midtown, Palo Alto, California]]
|
|| [[File:Fennec Fox.jpg|thumbThe [[fennec fox]] is the smallest species of fox]]
|
Conservation
Several fox species are endangered in their native environments. Pressures placed on foxes include
habitat loss and being hunted for pelts, other trade, or control.
[Ginsburg, Joshua Ross and David Whyte MacDonald. Foxes, Wolves, Jackals, and Dogs . p.58.] Due in part to their opportunistic hunting style and industriousness, foxes are commonly resented as nuisance animals.
[Bathgate, Michael. The Fox's Craft in Japanese Religion and Culture . 2004. p.18.] Contrastingly, foxes, while often considered pests themselves, have been successfully employed to control pests on fruit farms while leaving the fruit intact.
[McCandless, Linda Foxes are Beneficial on Fruit Farms. nysaes.cornell.edu (1997-04-24)]
Urocyon littoralis
The
island fox, though considered a near-threatened species throughout the world, is becoming increasingly endangered in its
endemic environment of the California Channel Islands.
A population on an island is smaller than those on the mainland because of limited resources like space, food and shelter. Island populations are therefore highly susceptible to external threats ranging from introduced predatory species and humans to
extreme weather.
On the California Channel Islands, it was found that the population of the island fox was so low due to an outbreak of canine distemper virus from 1999 to 2000 as well as predation by non-native . Since 1993, the eagles have caused the population to decline by as much as 95%. Because of the low number of foxes, the population went through an Allee effect (an effect in which, at low enough densities, an individual's fitness decreases). Conservationists had to take healthy breeding pairs out of the wild population to breed them in captivity until they had enough foxes to release back into the wild. Nonnative grazers were also removed so that native plants would be able to grow back to their natural height, thereby providing adequate cover and protection for the foxes against golden eagles.
Pseudalopex fulvipes
Darwin's fox was considered critically endangered because of their small known population of 250 mature individuals as well as their restricted distribution.
However, the
IUCN have since downgraded the conservation status from crictically endangered in their 2004 and 2008 assessments to
endangered in the 2016 assessment, following findings of a wider distribution than previously reported.
On the
mainland, the population is limited to Nahuelbuta National Park and the surrounding Valdivian rainforest.
[ Similarly on Chiloé Island, their population is limited to the forests that extend from the southernmost to the northwesternmost part of the island.][ Though the Nahuelbuta National Park is protected, 90% of the species live on Chiloé Island.]
A major issue the species faces is their dwindling, limited habitat due to the cutting and burning of the unprotected forests.[ Because of deforestation, the Darwin's fox habitat is shrinking, allowing for their competitor's (chilla fox) preferred habitat of open space, to increase; the Darwin's fox, subsequently, is being outcompeted.] Another problem they face is their inability to fight off diseases transmitted by the increasing number of pet dogs.[ To conserve these animals, researchers suggest the need for the forests that link the Nahuelbuta National Park to the coast of Chile and in turn Chiloé Island and its forests, to be protected. They also suggest that other forests around Chile be examined to determine whether Darwin's foxes have previously existed there or can live there in the future, should the need to reintroduce the species to those areas arise. And finally, the researchers advise for the creation of a captive breeding program, in Chile, because of the limited number of mature individuals in the wild.][
]
Relationships with humans
Foxes are often considered pests or nuisance creatures for their opportunistic attacks on poultry and other small livestock. Fox attacks on humans are not common.[Barratt, Sarah and Martin Barratt. Practical Quail-keeping . 2013.] Many foxes adapt well to human environments, with several species classified as "resident urban carnivores" for their ability to sustain populations entirely within urban boundaries. Foxes in urban areas can live longer and can have smaller litter sizes than foxes in non-urban areas.[Iossa, G. et al. A Taxonomic Analysis of Urban Carnivore Ecology , from Urban Carnivores. Stanley Gehrt et al. eds. 2010. p.174.] Urban foxes are ubiquitous in Europe, where they show altered behaviors compared to non-urban foxes, including increased population density, smaller territory, and pack foraging.[Francis, Robert and Michael Chadwick. Urban Ecosystems 2013. p.126.] Foxes have been introduced in numerous locations, with varying effects on indigenous flora and fauna.[See generally Long, John. Introduced Mammals of the World . 2013.]
In some countries, foxes are major predators of rabbits and hens. Population oscillations of these two species were the first nonlinear oscillation studied and led to the derivation of the Lotka–Volterra equation.[Sprott, Julien. Elegant Chaos 2010. p.89.][Natalia Komarova. Axiomatic Modeling in Life Sciences , from Mathematics and Life Sciences. Alexandra Antoniouk and Roderick Melnik, eds. pp.113–114.]
As food
Fox meat is edible, though it is not considered a common cuisine in any country.
Hunting
Fox hunting originated in the United Kingdom in the 16th century. Hunting with dogs is now banned in the United Kingdom,[ Fox Hunting. North West League Against Cruel Sports Support Group. nwlacs.co.uk] though hunting without dogs is still permitted. Red foxes were introduced into Australia in the early 19th century for sport, and have since become widespread through much of the country. They have caused population decline among many native species and prey on livestock, especially new lambs.
Domestication
There are many records of domesticated red foxes and others, but rarely of sustained domestication. A recent and notable exception is the Russian silver fox, which resulted in visible and behavioral changes, and is a case study of an animal population modeling according to human domestication needs. The current group of domesticated silver foxes are the result of nearly fifty years of experiments in the Soviet Union and Russia to de novo domesticate the silver morph of the red fox. This selective breeding resulted in physical and behavioral traits appearing that are frequently seen in domestic cats, dogs, and other animals, such as pigmentation changes, floppy ears, and curly tails. Notably, the new foxes became more tame, allowing themselves to be petted, whimpering to get attention and sniffing and licking their caretakers.[Kenneth Mason, Jonathan Losos, Susan Singer, Peter Raven, George Johnson(2011) Biology Ninth Edition, p. 423. McGraw-Hill, New York..]
Urban settings
Foxes are among the comparatively few mammals which have been able to adapt themselves to a certain degree to living in urban (mostly suburban) human environments. Their omnivorous diet allows them to survive on discarded food waste, and their skittish and often nocturnal nature means that they are often able to avoid detection, despite their larger size.
Urban foxes have been identified as threats to cats and small dogs, and for this reason there is often pressure to exclude them from these environments.
The San Joaquin kit fox is a highly endangered species that has, ironically, become adapted to urban living in the San Joaquin Valley and Salinas Valley of southern California. Its diet includes mice, ground squirrels, rabbits, hares, bird eggs, and insects, and it has claimed habitats in open areas, golf courses, drainage basins, and school grounds.
Though rare, bites by foxes have been reported; in 2018, a woman in Clapham was bitten on the arm by a fox after she had left the door to her flat open.
In popular culture
The fox appears in many cultures, usually in folklore. There are slight variations in their depictions. In European, Persian, East Asian, and Native American folklore, foxes are symbols of cunning and trickery—a reputation derived especially from their reputed ability to evade hunters. This is usually represented as a character possessing these traits. These traits are used on a wide variety of characters, either making them a nuisance to the story, a misunderstood hero, or a devious villain.
In East Asian folklore, foxes are depicted as possessing magic powers. Similar to in the folklore of other regions, foxes are portrayed as mischievous, usually tricking other people, with the ability to Human guise. Others depict them as mystical, sacred creatures who can bring wonder or ruin. fox spirit appear in Chinese folklore, literature, and mythology, in which, depending on the tale, they can be a good or a bad omen. The motif was eventually introduced from Chinese to Japanese and Korean cultures.
The constellation Vulpecula represents a fox.
Notes
External links