Skunks

Skunks
Striped skunk ( Mephitis mephitis )
Systematics
Subclass : Higher mammals (Eutheria) Superordinate : Laurasiatheria Order : Predators (Carnivora) Subordination : Canine (Caniformia) Superfamily : Marten relatives (Musteloidea) Family : Skunks
Scientific name
Mephitidae
Bonaparte , 1845
Genera
Striped Skunks ( Mephitis ) Fleckenskunks ( Spilogals ) Piglet Skunks ( Conepatus ) Smelly badger ( mydaus )

The Skunks , also Skunke , colloquially skunks (Mephitidae), are a family of predators . The twelve species in this group live primarily on the American continent ; Genetic studies have also confirmed that the Southeast Asian stink badgers belong to this group.

etymology

The technical term "Skunk" comes from an Algonquin language (derived from "Seganku") through English mediation .

features

general characteristics

Skunks reach a head body length of about 12 to a maximum of about 51 centimeters, a tail length of 7 to 41 centimeters and a weight of 0.2 to 4.5 kilograms. They are correspondingly small to medium-sized predators and reach a body length that corresponds roughly to that of a small house cat in the larger species , while the smaller species are roughly the size of a squirrel . There is a strong overlap in body sizes between the species. The three species of white -legged skunk living in the north ( piglet skunk , Amazon skunk and Andean skunk ) with a head-trunk length of up to 50 centimeters are the largest representatives of the skunks. The Asian stink badgers are also of this size, but they have a significantly shorter tail. The striped skunk lies behind these species with a head-trunk length of up to 40 centimeters, but together with the very long tail is significantly longer than the stink badger. The hooded skunk , the Patagonian skunk and the species of the spotted skunk are up to 30 centimeters long, the dwarf spotted skunk from Mexico with a head-torso length of a maximum of 21 centimeters is the smallest type of skunks.

All skunks are characterized by their contrasting fur . The basic color is black or dark brown, the face, the trunk and also the tail are provided with white stripes or spots. The trunk is elongated and rather slender and the legs are relatively short. The front paws in particular have long, curved claws that are ideal for digging. The tail is bushy in all American species, but only very short in the stink badger. The snout is elongated in most species, eyes and ears are relatively small.

Anal glands and defense secretions

A characteristic feature of all representatives of the Skunks are the pronounced, paired anal glands , which secrete a strongly smelling secretion that can be sprayed up to 6 meters. These glands are greatly enlarged in them compared to other predators.

The secretion is sprayed against a potential attacker from the two anal glands if he does not react to the warning by stamping his forepaws and lifting his tail. The Skunk injects several milliliters of the secretion, which has a long-lasting, unpleasant odor and is also irritating to tears.

Composition of the Defense Secretariat

Ingredients of the anal secretions of skunks ( Mephitis mephitis ). The relative mass fraction in% is given in brackets after the substance name.

The main alkanethiols responsible for the smell of the glandular secretions (from top to bottom): ( E ) -2-butenthiol (40%), 3-methylbutanethiol (22%) and 2-quinoline methanethiol (7%).

Thioesters (top to bottom): ( E ) -2-butenylthioacetate (15%), 3-methylbutylthioacetate (2%) and 2-quinoline methylthioacetate (7%).

2-methylquinoline (7%)

Research into anal gland secretion has been carried out in several approaches since the 19th century, so that today there is a fairly precise idea of ​​its composition. The German chemist Friedrich Wöhler and his assistant T. Swarts were able to prove as early as 1868 that the secretion is a mixture of substances that consists of at least one sulfur and one nitrogen component. In 1896, the chemist Thomas Aldrich was able to present more specific properties of the substance. He described the secretion as a " clear, oily liquid with a golden yellow to light amber color with a characteristic, penetrating and extremely strong odor with a specific density of 0.939 ". In addition, Aldrich identified a butanethiol as its essential component through the boiling point of a fraction of the secretion . A year later, together with Jones, he identified 2-methylquinoline as the second essential component and a second nitrogen and sulfur-containing substance, which was still unknown at the time. In 1945, the American chemist Philip Stevens isolated the substance bis (2-butenyl) sulfide from the secretion while he was actually looking for a substance similar to muscon , the odorous substance of musk .

In 1975 Andersen and Bernstein first used gas chromatography to analyze the secretion. The scientists identified 2-butene-1-thiol and 3-methyl-1-butanethiol with a total content of around 66% as the main components and (2-butenyl) methyl disulfide as the third most common compound with a content of around 7%. By combining gas chromatography with mass spectrometry in 1982 , the two scientists were able to detect a total of 160 components, 150 of which contain sulfur. 2-butene-1-thiol and 3-methyl-1-butanethiol could be confirmed as the main components, but (2-butenyl) methyl disulfide was no longer detected and the third most common component was now (2-butenyl) propyl sulfide . In addition, (3-methylbutyl) butyl disulfide and (2-butenyl) butyl disulfide were found and 2-methylquinoline was confirmed as a constituent. S- (3-methylbutyl) thioacetate was detected as the first thioester .

In 1990 William F. Wood worked on further clarification by immediately examining freshly obtained secretions with the gas chromatograph and mass spectrometry. He could not detect either (2-butenyl) methyl disulfide or (2-butenyl) propyl sulfide, instead he analyzed thioacetic acid S- (2-butenyl) ester as the third most common compound. He explained the lack of the components by the fact that these substances only formed during processing. 2-quinolylmethanethiol and thioacetic acid S- (2-quinolylmethyl) ester were newly identified .

distribution and habitat

Distribution areas of recent Skunk genera:
green : stink badgers ( Mydaus ),
purple : striped skunks ( Mephitis ),
blue : spotted skunks ( Spilogale ),
yellow : white- nosed skunks ( Conepatus )

The range of the ( recent ) Skunks living today is, with the exception of the two species of stink badger, on the American continent, where they occur in three genera from southern Canada through North and Central America to the southern tip of South America. The stink badgers live in Southeast Asia on the islands of Sumatra , Borneo , Java and the southern Philippines ( Palawan and neighboring islands).

Their habitats are rather open habitats such as steppes , semi-deserts and scrubland, they avoid overly dense forests and wetlands.

Way of life

Activity and social behavior

Play media file

Video recording of a strip skunk

Western Fleckenskunk ( Spilogale gracilis )

Skunks are usually crepuscular or nocturnal. During the day they retreat into hiding places; These can be structures that you dug yourself or that have been taken over by other animals ( e.g. marmots , badgers or ground squirrels ), but also crevices and hollow tree trunks, sometimes even buildings. In the evening or at night they go in search of food. They usually stay on the ground, only the Spotted Skunks climb trees. The strip skunks are known to hibernate during the cold season and often stay in their burrow for several weeks.

The animals are predominantly solitary, but generally do not react very aggressively to conspecifics. The territorial behavior is also not pronounced, the territories of individual animals can overlap widely. A burrow is sometimes used by several animals at the same time, the strip skunks sometimes form groups of up to 20 animals during hibernation, which live together in a burrow.

Defensive behavior

The skunks are best known for their defensive behavior, whereby the spraying of the anal gland secretion is only used in an emergency. Their high-contrast coloring alone should deter any predators; if that doesn't help, they use threatening gestures. They stamp their feet, bar their teeth or bend their tails forward and present their anus to the attacker. The spot skunks even do a handstand. Only when these measures are unsuccessful do they spray their secretion, usually aiming at the attacker's face. Striped skunks can hit predators six meters away, with other species this distance is shorter, with stink badgers about one meter.

Apart from the penetrating smell, the secretion has no harmful effects on healthy skin. However, it can cause vomiting and headaches on contact with the mucous membranes. If it gets in the eyes, the attacked person can temporarily go blind. The smell should be as good as impossible to remove from clothing.

Most animals learn from an encounter with a skunk. Larger mammals such as coyotes and pumas therefore rarely attack them. Birds of prey and owls are less deterred by the secretion, and their sense of smell is less pronounced.

food

Skunks are opportunistic omnivores , but they mainly eat meat. They prey on small mammals such as rodents and rabbits , birds , lizards , snakes and amphibians , but also insects and other invertebrates . As complementary foods, they consume vegetable material such as fruits , nuts and tubers . Many species show seasonal fluctuations in their diet; insects and fruits dominate in the summer months, while they tend to prey on small mammals in the cold season.

Reproduction

As a rule, Skunks have a fixed mating season, but this depends heavily on the habitat and climate. In some species, implantation is delayed, i.e. the fertilized egg cell stays in the uterus for a long time before it takes hold. In Western Spotted Skunk there can be eight months between mating and birth, even if the actual gestation period is much shorter and for most species should be between 40 and 65 days.

The female usually gives birth to four to five young, although the number of young in a litter can in rare cases be up to sixteen. The newborns are initially blind and hairless, but grow quickly. After 35 days they start to run around, after around two months they are weaned and after half a year or a year they leave the mother and become sexually mature.

Skunks generally have a low life expectancy , with many not surviving the first winter. In the wild they usually live to be five or six years old; in human care, no animal is older than twelve years.

Systematics

External system

For a long time the Skunks were as a family of martens considered (Mustelidae), which was also favored by the fact that within this group similarly colored species (for example, the Zorilla occur) and there are also species that can spray their Analdrüsensekret, such as the honey badger . According to genetic studies, however, they are not very closely related to the martens and are therefore given the status of a separate family in more recent classifications. Phylogenetic studies see them as a sister group of a taxon made up of small bears and martens.

Internal system

According to the current state of knowledge, the Skunks family contains twelve species, which are divided into four genera:

• The stink badgers ( Mydaus ), which used to be counted among the badgers (Melinae), are represented by two species on the Southeast Asian island world.
• The striped skunks ( Mephitis ) comprise two species that live in North and Central America .
• The Fleckenskunks ( Spilogale ) are composed of four types and are also found in North and Central America.
• The white-nosed kunks ( Conepatus ) are characterized by their pig-like snouts and live with four species across the American continent .

Genus stink badgers ( Mydaus F. Cuvier , 1825) - 2 species
German name	Scientific name	distribution	Hazard level Red List of IUCN	Remarks	image
Sunda stink badger	Mydaus javanensis ( Desmarest , 1820)		( Least Concern - not at risk)	3 subspecies Lives on Java , Sumatra , the Natuna Islands and Borneo
Palawan smelly badger	Mydaus marchei ( Huet , 1887)		( Least Concern - not at risk)	monotypically Lives in Palawan
Genus Streifenskunks ( Mephitis E. Geoffroy Saint-Hilaire & F. Cuvier , 1795) - 2 species
German name	Scientific name	distribution	Hazard level Red List of IUCN	Remarks	image
Strip skunk	Mephitis mephitis ( Schreber , 1776)		( Least Concern - not at risk)	13 subspecies Its range extends from central and southern Canada over large parts of the USA to northern Mexico.
Hooded skunk	Mephitis macroura Lichtenstein , 1832		( Least Concern - not at risk)	4 subspecies Its range extends from the southern USA to northwestern Costa Rica
Genus Fleckenskunks ( Spilogale J. E. Gray , 1865) - 4 species
German name	Scientific name	distribution	Hazard level Red List of IUCN	Remarks	image
Western patchwork skunk	Spilogale gracilis Merriam , 1890		( Least Concern - not at risk)	7 subspecies Lives in western North and Central America , its range extends from British Columbia and Wyoming to central Mexico
Eastern patchwork skunk	Spilogale putorius Linnaeus , 1758		( Least Concern - not at risk)	3 subspecies is native to the eastern half of the USA , from Wyoming and Texas to Florida
Dwarf stain skunk	Spilogale pygmaea Thomas , 1898		( Vulnerable - endangered)	3 subspecies Inhabits a small area along the Pacific coast of Mexico
Southern patch skunk	Spilogale angustifrons Howell , 1902		( Least Concern - not at risk)	5 subspecies comes up from central Mexico Costa Rica before
Genus Weißrüsselskunks ( Conepatus J. E. Gray , 1837) - 4 species
German name	Scientific name	distribution	Hazard level Red List of IUCN	Remarks	image
Andean skunk	Conepatus chinga ( Molina , 1782)		( Least Concern - not at risk)	7 subspecies Lives in central South America, from central Peru and central Brazil to Chile and northern Argentina
Patagonian skunk	Conepatus humboldtii J. E. Gray , 1837		( Least Concern - not at risk)	3 subspecies Is native to Patagonia , i.e. southern Argentina and Chile
Piglet kunk	Conepatus leuconotus ( Lichtenstein , 1832)		( Least Concern - not at risk)	3 subspecies Is distributed from southern Colorado and Texas to Nicaragua , Conepatus mesoleucus is a synonym
Amazon Skunk	Conepatus semistriatus ( Boddaert , 1785)		( Least Concern - not at risk)	6 subspecies Come in southern Mexico, northern South America to northern Peru and eastern Brazil before

Skunks    † paleomephitis      † Promephitis      Smelly badger ( mydaus )      † " Martinogale "      New World Skunks (Mephitini)

Phylogenetic systematics of the Skunks   Skunks    Smelly badger ( mydaus )      Striped Skunks ( Mephitis )      Fleckenskunks ( Spilogals )      White-legged skunk ( Conepatus )

Within the Skunks, the fossil species of the genus Promephitis were compared to the (recent) stink badgers ( Mydaus ) from Southeast Asia, which still live in two species . Together, Promephitis and the stink badger probably form the sister group of the fossil species Palaeomephitis steinheimensis , which is considered the oldest known species of the Skunks.

Within the recent genera, the stink badgers represent the most primitive genus, the common taxon from them and the fossil genera mentioned is compared to all other skunks living today and other fossil forms as the most primitive group. According to molecular biological data, the time of the separation of the stink badger from the American taxa was about 20.7 million years ago in the early Miocene .

The fossil record suggests colonization of North America in the middle to late Miocene , and within the New World Skunks (Mephitini), i.e. the species of Skunks living on the American continent, the extinct genus Martinogale is considered the oldest genus. According to the phylogenetic analysis of the genus, all (recent) American Skunk genera that are alive today have developed from the line of ancestry from which the three Martinogale species originated, and thus come from a single paleogeographical leap from the Eurasian to the (North) American continent. However, since these represent side branches of the lineage and not a common taxon , martinogale can be considered paraphyletic .

Among the recent American skunks, the South American white-nosed skunks ( Conepatus ) represent the most original genus. These form the sister group to a taxon that is formed from the two Central and North American genera the striped skunks ( Mephitis ) and the spotted skunks ( Spilogale ). The separation of the line that led to the white-legged buffalo from the ancestors of the other species is molecular-biologically dated to a point in time about 16 million years ago, the radiation of the species within the white-boneskunks took place about 11.2 million years ago. According to these data, immigration to the South American continent took place long before the Central American land bridge was formed about 3 million years ago. The oldest known fossils of the White Nosebos are from Conepatus sanmiguelensis from central Mexico from the early Pliocene , about 3 to 4 million years ago. In South America, the genus was first detected in Argentina about 2.5 million years ago.

The ancestors of the strip skunks and the spotted skunks separated about 12 million years ago. Within the Spotted Skunks, radiation to the four species known today took place around 3 million years ago, making this genus the youngest among the Skunks.

Skunks and people

North American strip skunks

Skunks are persecuted by humans for a variety of reasons. On the one hand, they are feared as carriers of rabies ; on the other hand, they occasionally invade poultry holdings. After successfully eliminating the odor of skunk fur, demand increased after 1870 and fur remained very fashionable for fur clothing until after World War I. At times the skunk was even kept on fur farms ; the fur is currently hardly used. Another source of danger is road traffic, to which many animals fall victim, especially in North America .

Nevertheless, skunks are widespread and are not endangered species, only the dwarf spotted skunk is listed as endangered (vulnerable) by the IUCN .

Individual evidence

1. ↑ Max Bachrach: Fur. A Practical Treatise. Prentice-Hall, Inc., New York 1936, p. 410.
2. ↑ books.google.de. Friedrich Goethe: The behavior of the mustelids . Verlag Walter de Gruyter, p. 45. Accessed February 28, 2016.
3. ↑ Wolfgang Legrum: Fragrances, between stench and fragrance. Vieweg + Teubner Verlag (2011) p. 55, ISBN 978-3-8348-1245-2 .
4. ↑ ^{a b c} Klaus Roth : Mephitis mephitis, you stink so much! Chemistry in our time 37, 2003, pp. 358-361.
5. ↑ Mydaus javanensis in the endangered Red List species the IUCN 2008 Posted by: B. Long, J. Hon, MJ Azlan, JW Duckworth, 2008. Accessed 28 December 2011 ..
6. ↑ ^{a b c d e f g h i j k l} Don E. Wilson & DeeAnn M. Reeder (eds.): Mephitidae in Mammal Species of the World. A Taxonomic and Geographic Reference (3rd ed).
7. ↑ Mydaus marchei in the endangered Red List species the IUCN 2008 Posted by: B. Tabaranza, L. Ruedas, P. Widmann, J. Esselstyn, 2008. Accessed 28 December 2011 ..
8. ↑ Mephitis mephitis in endangered species red list of the IUCN 2008. Posted by: F. Reid, K. slipway, 2008. Accessed 28 December 2011 ..
9. ↑ Mephitis macroura in the endangered Red List species the IUCN 2008. Posted by: AD Cuarón, F. Reid, K. slipway, 2008. Accessed 28 December 2011 ..
10. ^ Spilogale gracilis in the IUCN Red List of Threatened Species 2013.1. Posted by: AD Cuarón, F. Reid, K. Helgen, 2008. Retrieved August 7, 2013 ..
11. ^ Spilogale putorius in the Red List of Endangered Species of the IUCN 2013.1. Posted by: AD Cuarón, F. Reid, K. Helgen, 2008. Retrieved August 7, 2013 ..
12. ^ Spilogale pygmaea in the Red List of Threatened Species of the IUCN 2013.1. Posted by: AD Cuarón, F. Reid, K. Helgen, 2008. Retrieved August 7, 2013 ..
13. ↑ Spilogale angustifrons in the Red List of Threatened Species of the IUCN 2013.1. Posted by: F. Reid, R. Timm, KA Helgen, 2008. Retrieved on August 7, 2013 ..
14. ↑ Conepatus chinga in the IUCN Red List of Threatened Species 2013.1. Posted by: L. Emmons, K. Helgen, 2008. Retrieved August 7, 2013 ..
15. ↑ Conepatus humboldtii in the IUCN Red List of Threatened Species 2013.1. Posted by: L. Emmons, K. Helgen, 2008. Retrieved August 7, 2013 ..
16. ^ Conepatus leuconotus in the IUCN Red List of Threatened Species 2013.1. Posted by: AD Cuarón, F. Reid, K. Helgen, 2008. Retrieved August 7, 2013 ..
17. ^ Conepatus semistriatus in the IUCN Red List of Threatened Species 2013.1. Posted by: AD Cuarón, F. Reid, K. Helgen, 2008. Retrieved August 7, 2013 ..
18. ↑ ^{a b c d e} Katrin Nyakatura, Olaf RP Bininda-Emonds: Updating the evolutionary history of Carnivora (Mammalia): a new species-level supertree complete with divergence time estimates. BMC Biology 10, 2012. doi: 10.1186 / 1741-7007-10-12 .
19. ↑ ^{a b c} Mikko Haaramo: Mephitinae in Mikko's Phylogeny Archive.
20. ↑ Mieczysław Wolsan: Oldest mephitine cranium and its implications for the origin of skunks. Acta Palaeontologica Polonica 44 (2), 1999, pp. 223-230. ( Full text ; PDF; 2.0 MB).
21. ↑ ^{a b} Jerry W. Dragoo, Steven R. Sheffield: Conepatus leuconotus (Carnivora: Mephitidae) . In: Mammalian Species . tape 827 , 2009, p. 1-8 ( abstract ).
22. ↑ Xiaoming Wang, David P. Whistler, Gary T. Takeuchi: A new basal skunk Martinogale (Carnivora, Mephitinae) from late miocene Dove Spring Formation, California, and origin of New World Mephitines. In: Journal of Vertebrate Paleontology. Volume 25, No. 4, 2005, pp. 936-949 ( abstract ).
23. ↑ Xiaoming Wang, Óscar Carranza-Castañeda: Earliest hog-nosed skunk, Conepatus (Mephitidae, Carnivora), from the early Pliocene of Guanajuato, Mexico and origin of South American skunks. In: Zoological Journal of the Linnean Society. 154 (2), 2008, doi: 10.1111 / j.1096-3642.2008.00411.x , pp. 386-407.
24. ↑ Christian Franke, Johanna Kroll: Jury Fränkel 's Rauchwaren-Handbuch 1988/89. 10th, revised and supplemented new edition. Rifra-Verlag Murrhardt, pp. 63-65.

literature

• Ronald M. Nowak: Walker's Mammals of the World . 6th edition. Johns Hopkins University Press, Baltimore 1999, ISBN 0-8018-5789-9 (English).
• John J. Flynn et al .: Molecular phylogeny of the Carnivora (Mammalia): Assessing the impact of increased sampling on resolving enigmatic relationships. Systematic Biology 54 (2), 2005, ISSN  1063-5157 , doi: 10.1080 / 10635150590923326 , pp. 1-21.
• DE Wilson and DM Reeder: Mammal Species of the World . Johns Hopkins University Press, 2005, ISBN 0-8018-8221-4 .

Web links

Commons : Skunks (Mephitidae)  - Collection of images, videos, and audio files

Wiktionary: Skunk  - explanations of meanings, word origins, synonyms, translations

Wiktionary: Skunk  - explanations of meanings, word origins, synonyms, translations

• More information about the skunks and individual species
• Photo diary of the development of a skunk from birth to adult
• Skunks on the IUCN Red List of Threatened Species 2010. Retrieved February 22, 2011.