Rattlesnakes
| Rattlesnakes | ||||||||||||
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Texas rattlesnake ( Crotalus atrox ) |
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| Crotalus | ||||||||||||
| Linnaeus , 1758 |
The rattlesnakes ( Crotalus ) are a genus within the pit vipers (Crotalinae). They are mostly medium-sized venomous snakes . The largest species, the diamond rattlesnake ( Crotalus adamanteus ) and the Texas rattlesnake ( Crotalus atrox ), can reach maximum lengths of over two meters. The distinguishing feature of all species is the tail rattle , a structure at the end of the tail consisting of horn rings, with which rattling noises can be produced as a warning sound . This lack only young animals and the only on the island of Santa Catalina in the Gulf of California native Santa Catalina rattlesnake ( Crotalus catalinensis ). The genus includes 29 species. The occurrence of rattlesnakes is restricted to America .
features
External features
These snakes usually have a stocky body with an average length of 0.50 to one meter. The longest species is the diamond rattlesnake ( C. adamanteus ) with an average length of about 1.20 to 1.40 meters and a maximum length of up to 2.40 meters. The Texas rattlesnake ( C. atrox ) and the shower rattlesnake ( C. durissus ) can also reach lengths of over two meters, but are usually also significantly smaller. The weight of very large specimens can reach two to five kilograms and is therefore only comparable to that of the African Gaboon viper ( Bitis gabonica ) and the South American bushmaster ( Lachesis muta ) among the venomous snakes . A number of montane species, however, only reach lengths of less than 0.50 meters; these are thus as small as the three species of dwarf rattlesnakes (genus Sistrurus ). In most species the males become longer than the females; an exception is the sidewinder rattlesnake ( C. cerastes ), in which the females are the longer sex. In contrast, the females of all species become significantly thicker, and females are usually around 20 percent heavier than males of the same length.
Strongly keeled back and flank scales surround the center of the body in 21–29 rows, depending on the species. The basic color of all rattlesnakes is adapted to the habitat and ranges from yellowish to greenish, reddish to brown and black, depending on the species and population . A series of darker, oval or rhombus-shaped spots often runs down the back and along the sides. Diamond -shaped spots with a clear border of bright rows of scales, which are called " diamonds " and are eponymous for some species, are very common . In addition, there are simply spotted and unmarked color variants, especially in the area of the neck or the rear end patterns can also become ribbons. As with most snakes, the ventral side consists of a series of non-keeled abdominal scales (ventralia) and is usually monochrome, interspersed with light and dark speckles. A sexual dimorphism is unique to the Rock Rattlesnake ( Crotalus lepidus ) and a subspecies of the Mexican Plateau Rattlesnake ( Crotalus triseriatus armstrongi indistinguishable), all other species are males and females on the basis of color. Albinos and melanistic animals have been described in a number of species, but the former in particular are disadvantaged in the wild due to their lack of camouflage and are rarely likely to survive for long periods of time. Especially in more northern populations, melanistic individuals have the advantage that the dark color leads to faster heating of the body; in general, more northern populations of some species are significantly darker than southern populations of the same species.
The rather flat head with the vertically slit pupils stands out clearly from the slender neck. It is mostly triangular to shovel-shaped and has its widest point behind the eyes. The very large poison glands of the animals are located at this point . The snout is usually more or less rounded. In relation to the body, the head is relatively large, especially in small species and juvenile snakes. The spotted rattlesnake ( C. mitchellii ) and the tiger rattlesnake ( C. tigris ) have a very flat head compared to all other species. With the exception of the large supraocularia (over-eye shields ), the head is covered with small scales, and only in the area of the front snout have rattlesnakes other shields such as the unpaired rostral directly above the mouth opening and the two nasalia that cover the nostrils. This is where they can be distinguished from the dwarf rattlesnakes, which have nine large head shields on the top of their heads. The scales and shields are largely uniform in all rattlesnakes, only in the sidewinder rattlesnake the supraocularia form horn-like growths above the eyes. The head is usually uniformly dark or light in color, with a clearly separated temple band in almost all species extending over the eyes to the corner of the mouth. This usually represents a contrast to the basic head color and serves to camouflage the eyes.
The tail of almost all rattlesnakes is very short compared to other snakes. Since rattlesnakes are ground-living, they do not need a tail to be used when climbing. Also, a short tail can be made to vibrate more easily to use the tail rattle. An exception is the long-tailed rattlesnake ( Crotalus stejnegeri ), which only forms a short tail rattle and which only makes the tip of its tail vibrate. The tail is often banded in black and white before the tail rattle; some species, such as the black-tailed rattlesnake ( Crotalus molossus ), have dark to black tails. The tail end of the rattlesnakes is formed by the tail rattle; a structure of several loosely nested horn scales . These are the former scales of the tip of the tail, which are the only ones that are not shed during the moult; accordingly, the rattle is lengthened with each moult . In the wild, the end links of the rattle occasionally break off, so that the number of end links only corresponds to the previous number of molts in young snakes. An exception is the Santa Catalina rattlesnake ( C. catalinensis ), which does not form a tail rattle.
Sense organs
The sense organs of rattlesnakes focus like all snakes on her head. The eyes , Jacobson's organ and the pit organs play an important role.
The eyes are specially adapted to night vision, which means that the vertical pupil is only slit-shaped during the day. The color of the iris usually corresponds to the color of the color stripe that runs over the eye, and is accordingly dark brown to black in most species, but can also be very light to pink. Jacobson's organ corresponds to that of other scale reptiles . It lies in the upper jaw and analyzes the molecules that are brought to it by the two tips of the tongue. Nerve rings that are connected to the brain via the olfactory nerve end in the sensory organ .
A characteristic of the pit vipers is coated on both sides of the head between the nostrils and eyes located pit organ by means of which thermal radiation is detected. The giant snakes have developed a convergent , i.e. independently acquired, organ . With the help of the pit organs, rattlesnakes can detect temperature differences of 0.2 to 0.4 ° C and thus recognize the mostly warm-blooded prey animals very well. Even lizards can be identified because they are usually a bit warmer than its surroundings.
Poison apparatus
The venomous apparatus of the rattlesnakes consists of the relatively long venomous teeth in the upper jaw and the venomous glands located in the head behind the eyes. A canal runs between the teeth and the glands. As with all vipers, the poison fangs sit on the front end of the upper jaw and are folded back into the mouth when at rest. They lie in a fleshy sheath that retracts when unfolded and reveals the actual teeth. The teeth sit at the front end of the greatly shortened upper jawbone and are folded out when the mouth is opened. They contain a venom canal with an outlet near the tip of the tooth (tubular tooth, solenoglyphic tooth). The venom glands are surrounded by muscles that squeeze the venom out of the glands when bitten. Dry bites, i.e. bites that do not release poison, are rather rare in rattlesnakes. The fangs can be replaced; for this purpose, a new tooth grows right next to the existing one and then takes over its role. As a result, rattlesnakes can have four functioning fangs at times.
distribution and habitat
Distribution area
Rattlesnakes are common throughout America from Canada to Argentina , although few species are found in many areas. Most species are found in Mexico , 24 of the 29 known species live here, and twelve species are found exclusively in this country. Only two species are exclusively limited to the USA in their range , and rattlesnakes can be found in all states with the exception of Alaska and Hawaii . The greatest biodiversity is found here in Arizona with eleven species, eight in Texas , seven in New Mexico and six in California . Only the distribution area of the western rattlesnake ( C. viridis ) extends into the south of Canada, and the Massassauga ( Sistrurus catenatus ), one of the dwarf rattlesnakes, can also be found here .
The largest range is the shower rattlesnake ( C. durissus ), which is found in 14 subspecies from latitude 24th latitude north in Mexico to 35th latitude south in central Argentina, although it is very humid areas such as the tropical rainforest as well as extreme heights in the Andes and is therefore not available in Chile , Ecuador and Panama . At the other extreme, species are considered endemic species only to be found on individual islands. These include the rattleless Santa Catalina rattlesnake ( C. catalinensis ) on Santa Catalina Island or the Tortuga rattlesnake ( Crotalus tortugensis ) on Tortuga Island . The rarest species is Crotalus lannomi , of which fewer than ten are known from Jalisco , western Mexico, the first of which was described in 1966.
habitat
The habitats in which rattlesnakes can be found are very monotonous despite the large distribution area and the diversity of species. All species are land dwellers; they are rarely found in trees or bushes or in bodies of water, although some species can climb quite well and others swim well. With a few exceptions, rattlesnakes live in dry and warm areas, very often in deserts or steppe areas . Species whose range includes swamps and other humid areas, such as the diamond rattlesnake, also prefer dry microhabitats .
The sidewinder rattlesnake specializes in pure desert areas with loose sand, and many other species generally live in desert and semi-desert areas. There are also species that can only be found in rocky regions of the arid regions such as the spotted rattlesnake , the red diamond rattlesnake ( Crotalus ruber ) or the tiger rattlesnake . In Mexico in particular, there are many species that, as montane species, can only be found to a very limited extent in dry areas or dry forest areas in the high mountains. The highest occurrences of all rattlesnakes are found for the Mexican plateau rattlesnake ( Crotalus triseriatus ), which was found at a maximum height of 4572 meters and thus higher than any other American snake species. In the USA, the altitude record is likely held by the western rattlesnake , which was found at altitudes between 3300 and 3500 meters in the Sierra Nevada or the California Rocky Mountains . The same species lives together with the sidewinder rattlesnake below sea level around the Great Salt Lake and thus has the greatest height variance of all species.
Way of life
activity
As with all cold-blooded vertebrates, the activity of rattlesnakes is very dependent on temperatures. The times of activity change accordingly, especially in areas with distinct seasons. Species that live in these areas, especially the western rattlesnake , are accordingly especially nocturnal and crepuscular during the warmest seasons. In autumn and spring this activity shifts into the early morning hours or even into the daytime hours when solar radiation is needed for warming. During the winter, however, they hibernate and retreat to a suitable hiding place.
High mountain species are often completely diurnal because the night temperatures are too low. Species of the hot desert areas are almost completely nocturnal, especially in summer. With the exception of a few species, however, the desert dwellers also hibernate, as the temperatures in winter are usually too low. These rest periods can last from a few days to several months regionally. During these periods of rest, rattlesnakes seek out suitable hiding places, in which large numbers of individuals can be found when the snake population is high. The largest aggregations are the western rattlesnakes of the northern areas, which in extreme cases can make up up to 1,000 individuals. Red diamond rattlesnakes, Texas rattlesnakes, or spotted rattlesnakes can also be found in greater numbers; however, these rarely exceed 50 individuals. The largest known accumulations of the forest rattlesnake , which has the longest periods of rest at almost seven months, amounted to around 200 individual animals.
In spring, an increased overall activity can be observed in all species, since this is the time of mating and especially the males are looking for potential sexual partners.
nutrition
Rattlesnakes feed primarily on small mammals such as various mice , prairie dogs , chipmunks or rats and rabbits . These animals are recognized very well with the heat-sensitive pit organs due to their very warm body compared to the environment. Overall, mammals make up about 85 percent of the diet in rattlesnakes. It was found that the mortality of these prey from rattlesnakes is very high: In Idaho , about 14 percent of the squirrels and 11 percent of the cottontail rabbits are killed each year by rattlesnakes on the prairie . Birds make up around 10 percent of their prey, especially the nestlings of ground-breeding species. However, some species of rattlesnake also climb into bushes or low trees and hunt for nestlings or resting birds there. The remaining 5 percent of the diet is made up of lizards , amphibians or other snakes. However, lizards are the main source of food, especially in juvenile snakes and some smaller species.
Rattlesnakes hunt their prey mainly as ambulance hunters . They wait in suitable places until a prey animal of the right size comes by. Lurking places that are regularly visited by rodents based on their smell are preferred. The prey is perceived and located through the sensory organs of the head. When attacking, the snake pushes its front body forward and opens its mouth, whereby the poison fangs are unfolded and then struck into the prey. Then she pulls her head back and folds her teeth back in while the poison works. With the help of its senses of smell and warmth, the snake pursues its prey and grabs its head to swallow it. A medium-sized prey is usually enough for a few days as food.
Locomotion
Rattlesnakes, like other snakes, move primarily by snaking, with parts of their bodies pushing themselves off the unevenness of the ground laterally, or by crawling on the ventral scales, always pushing the front body forward and then pulling the rear body. The sidewinder rattlesnake has created a special type of locomotion that is unique among snakes . It moves sideways at a 45 degree angle across the sand, always rolling at two points with the entire body. The head is put on and rolled off, the entire body follows it, while the head is already touching down in a new place. This type of locomotion creates typical J-shaped tracks in the sand.
Reproduction and development
All rattlesnakes are viviparous ( ovoviviparous ); The main differences between the species are the size of the litter and the mating and birth times. The mating season falls in spring, especially for lowland species, and many of these species have a second mating season in autumn. The young snakes are born in summer, the second generation follows after wintering in spring. Highland species, on the other hand, only mate once in the summer and the young are born the following year. In many species, however, the females are only capable of childbearing every two years.
Both the males and the females mate with as many partners as possible during the mating season, and in all species with the exception of the sidewinder rattlesnakes, the males fight ritualized competitions with one another in order to mate individual females. You can find the females by means of their scent trail made up of pheromones . In mating fights, the competing males wrap their front bodies around each other and try to push the opponent to the ground (commentary fight). The fights can last for hours and are also interrupted by pauses until one of the males gives up and flees. The fights are mainly won by strong and large animals. As with other snakes, mating occurs when the male inserts his hemipenis into the female's cloaca and releases his sperm. The ovulation occurs only after mating . In the case of species that mate in summer or autumn, there can be a relatively long time between the two events, during which the sperm are stored in a special chamber in the female genital tract.
After ovulation, the eggs are fertilized and the young snakes begin to develop. The pregnant females spend significantly more time sunbathing and thus warming up their bodies, and in some species they gather in particularly suitable places. At birth, the young snakes are only enclosed by a thin egg shell from which they break out after a few minutes and move away from the place of birth; Brood care is unknown in rattlesnakes.
As with all other snakes, it also comes with the rattlesnakes to regular molts to enable growth. The first molt occurs after a few days of age, after which the young snakes molt up to seven times a year. After reaching adulthood, the number of moults decreases to an average of two to three per year, with the first moult usually taking place in spring after hibernation . Unlike all other snakes, in rattlesnakes (with the exception of the Santa Catalina rattlesnake ), the scales on the tip of the tail are not shed and these form the tail rattle that grows longer with each molt. In the phase before molting, the horny layer of the tail scale first thickened, and the new scale formed underneath. The older one gets caught in the new scale and therefore cannot be thrown off.
Male rattlesnakes become sexually mature at around four years of age, females at four to six years. The maximum age of rattlesnakes is unknown; under terrarium conditions, animals of individual species can live to be over 30 years old.
Predators, threatening and defensive behavior
Although rattlesnakes have effective defenses with their highly potent venom, they are still killed and eaten by a number of enemies. These include carnivorous mammals such as foxes , coyotes and also domestic dogs and cats , various birds such as the red-tailed buzzard ( Buteo jamaicensis ) and the cuckoo ( Geococcyx californianus ) and various types of snakes. The latter includes above all the non-poisonous king snake ( Lampropeltis getula ), which is immune to the poison of the rattlesnakes and kills them by entangling them.
The main defense strategy of the rattlesnakes is their camouflage through coloration and behavior. In addition, they often hide under stones or in bushes. When this passive defense does not work, an active and aggressive defense occurs, which is mainly used against large mammals. They then curl up on the ground and use their tail rattle to produce a clear warning sound, while fixing the potential opponent and, in extreme cases, biting. The warning from the very loud rattle is particularly effective for ungulates, which tend to come across rattlesnakes by chance and trample them on.
Imitation of rattlesnakes
Since the behavior of the rattlesnakes is very effective, especially against unspecialized predators, there are a number of other animals that imitate the behavior and especially the sound of the rattle and try to imitate a rattlesnake ( mimicry ). This can be observed above all in various non-poisonous snakes , which are also similar in color to rattlesnakes. These include the climbing snake ( Pantherophis ), the bull snake ( Pituophis melanoleucas ) and the western hook- nosed snake ( Heterodon nasicus ). Another unusual feature is the behavior of belonging to the owls Kaninchenkauzes ( Athene cunicularia ), who lives in underground burrows and also mimics the rattle of rattlesnakes at risk.
Evolution and systematics
According to a study published in 2016, the "rattling" of rattlesnakes and the associated anatomical peculiarities are probably derived from a behavior that can be observed in numerous relatives of the rattlesnake, the movement of the tail to and fro in a threatening situation.
Tribal history
The rattlesnakes evolved from other pit vipers only a few million years ago. The oldest fossils of this genus are only four to five million years old, the oldest fossils of American pit vipers are dated to an age of around 10 million years. Only two species of rattlesnakes that are no longer alive today have been given a name, Crotalus potterensis from California and Crotalus giganteus from Florida; all other fossils could be assigned to species that still exist today or are unidentified. The fossil species also lived in arid areas. Their way of life probably hardly differed from today's species.
External system
The closest relatives of the rattlesnakes are probably the dwarf rattlesnakes , the only other genus of snakes to have developed a tail rattle. They share other characteristics with the rattlesnakes, including, for example, the way of life that is very well adapted to dry and warm habitats. The main distinguishing feature is the different signage on the head, which consists of several large shields and is broken up into numerous individual scales in the rattlesnakes.
The triangular-headed adder ( Agkistrodon ) and the American lance-snake ( Bothrops ) are also closely related to the rattlesnakes and dwarf rattlesnakes . A possible cladogram of the close relatives of the rattlesnakes is accordingly:
| American pit vipers * |
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* American pit vipers (Crotalinae); only specified genera
In addition to these studies, there are also some working groups that question the monophyly of the rattlesnakes and consider the dwarf rattlesnakes to be part of the group. This is justified by the fact that the only essential difference lies in the scaling of the head, which was already developed in the form of large scales in the ancestors of both groups and must therefore be considered plesiomorphic in the dwarf rattlesnakes . This assumption is partly confirmed by molecular genetic studies, but partly also refuted.
species
The exact relationships within the rattlesnakes have not yet been researched in detail, although their distribution, morphological features and the composition of the poison in some species suggest a closer relationship. For example, the basilisk rattlesnake ( C. basiliscus ) and black-tailed rattlesnake ( C. molossus ) as well as the Texas rattlesnake ( C. atrox ), cedros rattlesnake ( C. exsul ), and the red diamond rattlesnake ( C. . ruber ) more closely related to each other than to other species. The forest rattlesnake ( C. horridus ) seems to be the most primitive species. A total of 29 species are distinguished today:
- Diamond rattlesnake ( Crotalus adamanteus , Beauvois 1799)
- Crotalus aquilus , Dorcas 1992
- Texas rattlesnake ( Crotalus atrox , Baird and Girard 1853)
- Basilisk rattlesnake ( Crotalus basiliscus , (Cope 1865))
- Santa Catalina rattlesnake ( Crotalus catalinensis , Cliff 1954)
- Sidewinder rattlesnake ( Crotalus cerastes , Hallowell 1854)
- Shiver rattlesnake or Cascaval ( Crotalus durissus , Linnaeus 1758)
- Baja rattlesnake ( Crotalus enyo , Cope 1861)
- Forest rattlesnake ( Crotalus horridus , Linnaeus 1758)
- Crotalus intermedius , Troschel 1866
- Crotalus lannomi , Tanner 1966
- Rock rattlesnake ( Crotalus lepidus , (Kennicott 1859))
- Spotted rattlesnake ( Crotalus mitchellii , (Cope 1861))
- Black-tailed rattlesnake ( Crotalus molossus , Baird and Girard 1853)
- Pacific rattlesnake ( Crotalus oreganus , Holbrook 1860)
- Mexican lance-head rattlesnake ( Crotalus polystictus , (Cope 1859))
- Prices rattlesnake ( Crotalus pricei , Van Denburgh 1895)
- Crotalus pusillus , Klauber 1952
- Red diamond rattlesnake ( Crotalus ruber , (Cope 1892))
- Mojave rattlesnake ( Crotalus scutulatus , (Kennicott 1859))
- Crotalus simus , Latreille In Sonnini & Latreille, 1801
- Long-tailed rattlesnake ( Crotalus stejnegeri , Dunn 1919)
- Tiger rattlesnake ( Crotalus tigris , Kennicott 1859)
- Tortuga rattlesnake ( Crotalus tortugensis , Van Denburgh and Slevin 1921)
- Crotalus totonacus , Gloyd & Kauffeld, 1940
- Banded mountain rattlesnake ( Crotalus transversus , Taylor 1944)
- Mexican plateau rattlesnake ( Crotalus triseriatus , (Wagler 1830))
- Western rattlesnake or prairie rattlesnake ( Crotalus viridis , Rafinesque 1818)
- Edged rattlesnake ( Crotalus willardi , Meek 1906)
Snake venom
Like most viper poisons, the poisons of the rattlesnakes are primarily hemotoxic , i.e. they mainly destroy cells of the blood and the tissues surrounding them and thus differ from the paralyzing neurotoxins that are mainly found in venomous snakes . Hemotoxins lead mainly to tissue destruction, internal bleeding and swelling and are very painful, but compared to most neurotoxins they kill less quickly. Some species of rattlesnake, such as the Mojave rattlesnake ( C. scutulatus ), produce both hemotoxic and neurotoxic components. Within the vipers, the composition is species-specific; and their composition is an important characteristic for identifying relationships within the snakes.
The exact composition of the venom of the rattlesnakes is still unknown and varies between species. The poisons of the widespread and larger species in the USA have been researched best, while those of many Mexican species have so far hardly been researched. The main part of the toxins make up enzymes such as proteases and phospholipases . While the former break down and break down proteins , the latter break down the phospholipids into fatty acids and lipophilic components. The proteases act as hemorrhagins very specifically and effectively on the wall structure of the small blood vessels that they destroy. This causes bleeding into the tissue, which additionally contained in the venom clotting enzymes that the thrombin are similar, and a modification of the endogenous blood fibrinogen are coagulation prohibit, reinforced. The interaction of these toxins leads to tissue damage, additional toxins such as myotoxins and the rattlesnake- specific crotamine attack the surrounding muscles. The neurotoxic poisons mainly contain a complex of a basic phospholipase A 2 and an inhibiting acidic protein. In the shower rattlesnake, the former is known as crotoxin , the latter as cropotin . The crotoxin only becomes active on the membrane of the motor end plates of a synapse and destroys it after the cropotin has been split off. The destruction of the synapse leads to paralysis, as no more neurotransmitters can be released.
The amount of venom released by a rattlesnake when it bites varies from around 50 mg ( dry matter ) in the very small species to around 400 mg in medium-sized snakes to over 1,000 mg in the largest species such as the diamond rattlesnake or the Texas rattlesnake. For laboratory mice, however, the LD 50 value for most of the larger rattlesnakes is around 3 to 5 mg / kg. These snakes have enough venom in their venom glands that would be sufficient to kill 3,000 to 5,000 mice. The haemotoxic part of the poison of the Mojave rattlesnake has an LD 50 value related to mice of about 3 mg / kg and thus corresponds to that of other rattlesnakes, the neurotoxic part, however, has an LD 50 value of only 0.24 mg / kg. The delivery of an average of 70 mg is sufficient to kill up to 7,500 mice, making this species the most poisonous snake in North America. The venom of the South American shower rattlesnake is comparable to that of the Mojave rattlesnake; However, at around 100 mg per bite, it releases a significantly larger amount of the poison.
Humans and rattlesnakes
Along with cobras and boa constrictor , the rattlesnakes belong to the group of snakes, which to this day have a particular fascination in the form of a mixture of fear and curiosity. Especially in the stories and myths of the American West, beginning with the Indians and European settlers of the Wild West era to the films of today, rattlesnakes play a major role as a potentially deadly and dangerous symbol of the deserts and prairies of America.
Toxic effect on humans
Rattlesnake bites are among the most common snake bites in North America. With the exception of the states of Maine , Delaware , Alaska and Hawaii , which do not have rattlesnakes, there have been reports of bites by these venomous snakes from all states of the USA. The states of North Carolina, Arkansas, Texas, Georgia, West Virginia and Mississippi represent the states with the most frequent bite accidents by rattlesnakes; the rate was a maximum of 19 bites per 100,000 inhabitants per year. Due to the sharp decrease in the number of rattlesnakes in almost all states in the last few decades, the bite rate has also fallen sharply. Most accidents occur while working on farms and especially during the peak snake activity times in spring and autumn, so that in areas with large rattlesnake populations in the deserts and prairies (New Mexico, California, Arizona) only a few accidents per year happen. Accordingly, adults between the ages of 20 and 40 are particularly affected; children under the age of ten are least likely to be bitten.
Only a few species are potentially fatally poisonous for humans, including above all the large species such as the diamond rattlesnake or the Texas rattlesnake due to the large amount of poison and the species with highly potent neurotoxins such as the Mojave rattlesnake or the shower rattlesnake. However, due to the usually quick availability of medical help and various antidotes that are used specifically for rattlesnake bites, the risk of a fatal bite is minimal. As a rule, there is a very painful swelling of the bite site with local blood cells and tissue destruction.
Indians were familiar with various plants that rattlesnakes avoided, such as the hazel . That is why the Indians sometimes tied such plants around the ankle as protection against snakebites.
Some Indian tribes such as the Comanche , Paiute and Nez Percé used the venom of the rattlesnakes as arrow poison. The Comanche were a number of other tribes in their respective language as snakes and of the Cheyenne as rattlesnakes referred.
Threat and protection
Rattlesnakes are particularly hunted in the southern states of the United States. So-called roundups are organized here every year , in which as many rattlesnakes of all species as possible are caught and then killed. The snakes are considered dangerous pests that should be killed at every encounter, and on the street they are also classified as fair game , approved for killing, and are accordingly often run over. Every year tens of thousands of rattlesnakes are killed in this way, and the populations of almost all species are falling accordingly. In addition, there are wild catches for keeping in terrariums and, on a smaller scale, traditional catches for preparing materials for Indian folk medicine or for nutrition. The latter is traditionally cultivated by the Native American population, but rattlesnake meat is also a popular delicacy and can be bought canned in the US South.
In addition to active hunting, especially those species that are not restricted to the deserts, also destroy the habitat, which pushes these species back further and further.
In recent years in particular, some species have been placed under protection and are no longer officially allowed to be caught or killed. Many desert species experience additional protection through the classification of their habitat as national parks or nature reserves, in which they are not allowed to be hunted. In the Red List of IUCN , however, is only the Aruba Rattlesnake ( C. durissus unicolor of batteries in the IUCN as a species C. unicolor ) listed as critically endangered.
Research history
Probably the first mention of rattlesnakes in literature comes from the Spaniard Pedro de Cieca de Leon in 1554, who described the sound of the rattle and the consequences of a bite of the shivering rattlesnake ( C. durissus ) in La Chronica del Peru . The first known illustration is by Francisco Hernandez from 1628. He described the behavior of rattlesnakes in his work Rerum Medicarum Novae Hispaniae seu Plantarum Animalium Mineralium Mexicanorum Historia and also points out that there are several species. The first Englishman to describe rattlesnakes, at least indirectly, was John Smith . In A Map of Virginia in 1612 he wrote that some Virginias Indians wore rattles made from snake tails as headdresses. The Oxford English Dictionary also attributes the first use of the word rattlesnake to Smith, dated 1630 , but a year earlier the Puritan clergyman Francis Higginson had written in his description of the New England Forests that there are snakes that “have rattles in their tails and who do not flee from man like others like others [snakes], but rush on him and bite him to death ” . Death occurs within a quarter of an hour if the person bitten does not chew on a medicinal root called "snake herb". In 1637 Thomas Morton, who also emigrated to New England, described the animals in New English Canaan :
- “ There is a creeping animal that has a rattle in its tail and knows its own age; for with every year of life its rattle grows around a joint, and the rattle sounds like peas in a bubble, and this animal is called a rattlesnake. "
In 1682, Edward Tyson published the first scientific description of the anatomy of rattlesnakes in the Philosophical Transactions of the Royal Society , in which the pit organs were also described. In many other texts, the knowledge about the snakes, as it is known today, was usually collected piece by piece. In 1758, Carl von Linné described the rattlesnakes as well as the forest, the shower and the dwarf rattlesnake (not until 1766 as C. miliarius ) in his Systema naturae . All other species of rattlesnakes were not described until later, mostly in the 19th century. Eight species did not follow until the 20th century, one of which was C. lannomi in 1966 and C. aquilus in 1992.
Mythology and Cultural History
Indian mythology
Very little is known about the mythological significance of the rattlesnakes among the Indians up to the arrival of the first Europeans, and only individual stories of the Indian tribes have been passed down to this day. The rattlesnake is the most important species of snake mentioned in the legends; however, it is usually counted among the negative powers.
According to an Indian legend, the rattlesnake emerged from the transformation of a shaman who hid a rattle behind his back and can still poison people through his magic to this day. In the Winnebago , on the other hand, the rattlesnake appears at the beginning of creation:
- When the Great Spirit created the earth and adorned it with grass and flowers, He put four mighty spirits with two rattlesnakes and two buffalo at its four corners to hold them tight.
The most famous mythological aspect of the rattlesnakes is undoubtedly the famous snake dance of the Hopi from northeast Arizona. It represents the conclusion of a rite that is supposed to bring rain to the Indians, whereby the snakes are supposed to act as mediators between humans and spirits. The dances are organized by two religious associations of the Hopi, the snake and the antelope brotherhood. The members of the Snake Brotherhood go into the desert on the fifth day of the nine-day rite and collect snakes, especially rattlesnakes ( C. viridis nuntius , known as the Hopi rattlesnake) and bull snakes ( Pituophis melanoleucas ), and on the eighth day there is a dance, which represents the symbolic marriage between a snake brother and a maize maiden. On the ninth day, the snakes are symbolically cleansed, the actual snake dance begins on the evening of this day. To the music of the antelope brothers, the snake brothers dance in groups of three, in which one always takes a snake and holds it with his mouth. As soon as the snake tries to bite, one of the other two dancers hits it with a snake whip. After each walk around the dance area, the dancer exchanges the snake until all snakes have danced once, after which they are brought to the center of the area and dusted with cornmeal . Finally, the snake brothers take the snakes and bring them back into the desert. Today the Hopi snake dance is a popular tourist attraction.
According to a Cherokee legend , the rattlesnake killed the Sun Daughter by biting off her head to keep the sun from burning people with its rays.According to traditional Cherokee beliefs, between the eagle - the central animal in their mythology - and the rattlesnake a deep enmity. That is why they only celebrated the dance in honor of the eagles in winter, when the rattlesnakes are sleeping and the eagles are therefore less irritated.
The Mesoamerican deity Quetzalcoatl is often depicted as a rattlesnake with feathers from the sacred bird Quetzal . Quetzalcoatl was considered a creator god by the Aztecs and Toltecs and was also worshiped by the Maya .
Modern superstition of North America
Many more modern rites and superstitious ideas about rattlesnakes developed among the European settlers, some of which still exist today. These refer mainly to the bite and venom of snakes and are partly adapted from European folk wisdom. For example, it is believed:
- A rattlesnake that bites a drunk or sick man will die from it.
- When a rattlesnake is killed, everyone who died from it should wake up again.
- If a bitten one survives the snake will die and if he dies the snake survives.
- A bitten tree will die, but it can also pass the poison on to a person who holds onto a branch.
- A rattlesnake never bites from behind or in the water. In addition, children under the age of seven or women are not bitten.
Pentecostal rituals
Because of their toxicity, rattlesnakes are used in the snake- handling ritual practiced by a few American Pentecostal churches . In doing so, those involved accept a bite as proof of their faith.
Use in literature
In addition to being processed in the myths and superstitions of the Indians and later the settlers of America, the rattlesnake was also mentioned in various ways in classical to modern literature. As early as 1783 Matthias Claudius used the image of the rattlesnake as a description of a sly man in the treatise Beauty and Innocence - A Sermon to the Girls :
- “But flee the man who does this! And if he were adorned with gold and pearls, he's a villain. Is a poisonous rattlesnake! It is true that nature spared him the rattle because she relied on his gifts and his discretion; but he was not worth the generosity and should wear one, and I would gladly put it in his hair bag , or hang one on his ear so that he would warn himself where he was going. "
In his poem Das Mordtal 1837, Adelbert von Chamisso described the encounter with a rattlesnake as follows:
- And wanted to stretch myself in need of rest
- When next to me sounded in the dry leaves
- A rattle, well suited to frighten me.
- It was the rattlesnake; jumped from the camp
- I looked up and saw the light of my fire
- The worm that I managed to destroy.
Johann Wolfgang von Goethe used the rattlesnake figuratively in his description of the siege of Mainz in the story Italienische Reise :
- Attracted by the wild, desolate danger, as if by the gaze of a rattlesnake, one rushed into the deadly rooms, walking, riding through the tranches, letting the howitzer shells boom over one's head and the debris tumbling down next to one;
In addition to these examples, the rattlesnake can be found both in the direct, but much more often in transferred form in many other places in the literature. The most famous authors who used them include Christian Dietrich Grabbe , Jean Paul , Karl Gutzkow , Friedrich Hebbel , Heinrich Heine , ETA Hoffmann , Arthur Schopenhauer , Ernst von Wildenbruch , Walt Whitman and Friedrich Nietzsche .
The rattlesnake was of course used primarily in travel and adventure literature, especially among authors who wrote stories about the Wild West. First and foremost, Karl May should of course be mentioned, in whose stories these animals appear regularly. But Jules Verne and Mark Twain also used the description of encounters with rattlesnakes to increase tension.
heraldry
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A rattlesnake and the words DONT TREAD ON ME (“Don't step on me”) adorn the First Navy Jack , the official flag of the American Navy . The design is the oldest American naval ensign from the American Revolutionary War ; it was first flagged in 1775 on the ship of John Paul Jones . The First Navy Jack was the official flag until 1777, but was then replaced by a stars and stripes. With a resolution of September 11, 2002, the flag with the rattlesnake was reintroduced after 225 years; in the war on terror it is supposed to convey a clear message.
The rattlesnake and the accompanying threat had already become a symbol of the revolutionaries, possibly under the influence of Benjamin Franklin's famous cartoon Join or Die (1754). Derived from this caricature, the Gadsden Flag was developed in 1775 , a coiled rattlesnake on a yellow background, under which the lettering is also placed. It was founded by Congressman Christopher Gadsden of South Carolina created and the commander of the Navy, Esek Hopkins , given the first Navyeinsatz as personal flag. The Gadsden Flag , which is still used on various occasions today, for example as a symbol of many followers of libertarianism , probably also developed into the First Navy Jack. Both flags show the rattlesnake with 13 rings on the tail rattle, corresponding to the number of states when the USA was founded.
Completely independent of the heraldic use of the rattlesnake in the USA, it is also shown in the national flag of Mexico and in the Mexican coat of arms . It is held in place by the claws and beak of an eagle perched on a cactus. The coat of arms is based on an Aztec legend about the founding of Tenochtitlán . The god Huitzilopochtli had instructed the people to find an eagle sitting on a cactus devouring a snake. This cactus should grow on a rock in the middle of a lake. After two hundred years of wandering, they found the promised sign on a small island in boggy Texcoco. Here they founded their new capital Tenochtitlán, today's Mexico City . The current coat of arms was redesigned in 1968 by Francisco Eppens Helguera and introduced by President Gustavo Díaz Ordaz .
Use in popular culture
Out of the fascination for the rattlesnakes, many other stories have developed that live on to the present day and have also found their way into modern popular culture. There are several films in which rattlesnakes play a role, from westerns to more or less modern horror and psychological thrillers and end-of-time scenarios.
In music, the rattlesnake is often seen as a symbol of particular hardness and coldness, which is why it is particularly present in hard rock as an image, Slash's Snakepit and the Texan band Pantera , who play a rattlesnake for their successful album The Great Southern Trendkill , are particularly known as a cover motif. Also on the Metallica album (the so-called “Black Album”) by the band Metallica of the same name , a rattlesnake is depicted, whose body shape corresponds to the Gadsden flag . Significantly , there is also the song Don't tread on me analogous to the label the flag.
In the film Natural Born Killers , the rattlesnake is a motif that appears regularly and, together with other snake images, runs through the entire film. John Carpenter's film Die Ratterschlange only has a misleading German title (in the English original "Escape from New York"). Since the main character Snake a cobra as a tattoo , has the nickname refers probably to "snake" in general.
Also on the sport, the symbolism of the rattlesnake is often transmitted prominent example is the Arizona Diamondbacks , a baseball team of the US Major League . These are named after the Eastern Diamondback , the Texas rattlesnake, and have it as a symbol in their logo on the player's cap.
The US wrestler Steve Austin uses his stage name, including "The Texas Rattlesnake".
Figurative meaning
The term "rattlesnake" was also transferred to other terms. The dictionary of German colloquial language lists four different uses. The term "poisonous like a rattlesnake" for an extremely vicious person refers to the snake venom of the animals and has been used in German-speaking countries since around 1930. The term “rattlesnake”, which has been in use at least since the 18th century, for an incompatible person, usually a woman, is to be understood in a similar way. In his drama Spring Awakening (1891) , for example, Frank Wedekind wrote of the spindly Mademoiselle Angélique, this rattlesnake in the paradise of my childhood .
The term "rattlesnake" refers to the sound of the tail rattle for an extremely talkative person, whereby "rattle" describes the constant chatter (in use since around 1500). Due to the clattering noise of the typewriter , the term rattlesnake had also been used since around 1900 to refer to a typist .
Sources and further information
Sources cited
Most of the information in this article has been taken from the sources given under literature; the following sources are also cited:
- ↑ Bradley C. ALLF, Paul AP thirst and David W. Pfennig: Behavioral Plasticity and the Origins of Novelty: The Evolution of the Rattlesnake Rattle. In: The American Naturalist. Volume 188, No. 4, 2016, pp. 475-483, doi: 10.1086 / 688017
- ↑ Christopher L. Parkinson, Scott M. Moody, Jon E. Alquist: Phylogenetic relationships of the 'Agkistrodon complex' based on mitochondrial DNA sequence data. In Symp. Zool. Soc. London 70, 1997; Pp. 63-78.
- ↑ e.g. in Christopher L. Parkinson: Molecular Systematics and Biogeographical History of Pitvipers as Determined by Mitochondrial Ribosomal DNA Sequences. Copeia, Vol. 1999, No. 3 (Aug. 2, 1999); Pp. 576–586 ( abstract )
- ^ For example in Alec Knight, David Styer, Stephan Pelikan, Jonathan A. Campbell, Llewellyn D. Densmore III, David P. Mindell: Choosing Among Hypotheses of Rattlesnake Phylogeny: A Best-Fit Rate Test for DNA Sequence Data. Systematic Biology 42, No. 3 (Sep. 1993); Pp. 356–367 ( abstract )
- ↑ Species list according to JA Campbell, WW Lamar WW: The Venomous Reptiles of the Western Hemisphere. Comstock Publishing Associates, Ithaca and London 2004, ISBN 0-8014-4141-2 . and ITIS
- ↑ Dietrich Mebs: Gifttiere - A manual for biologists, toxicologists, doctors, pharmacists. Wissenschaftliche Verlagsgesellschaft Stuttgart mbH, 1992; Pp. 237-240, ISBN 3-8047-1219-3 .
- ^ Mattison 1996, quoted from HM Parrish: Incidence of treated snakebites in the United States. In Public Health Report 81, 1963; P. 269 and FE Russell: The clinical problem of crotalid snake venom poisoning. In CY Lee (ed.): Handbook of Experimental Pharmacology, Snake Venoms 52, Springer Verlag Berlin 1979; P. 978.
- ↑ Bruno Hofmann: Indians of North America . Reinhold Liebig, Frauenfeld 2004.
- ^ Thomas W. Kavanagh: Comanche . In: William C. Sturtevant (Ed.): Handbook of North American Indians , Volume 13. Smithsonian Institution Press, Washington DC, 2001; Pp. 886-906.
- ↑ Crotalus unicolor in the endangered Red List species the IUCN 2006. Posted by: RA Odum, 1996. Retrieved on January 7 of 2007.
- ↑ Some on their heads weare the wing of a bird or some large feather, with a Rattell. Those rattels are somewhat like the chape of a rapier but lesse, which they take from the taile of a snake. In: A Map of Virginia. With a Description of the Countrey, The Commodities, People, Government and Religion. Written by Captaine Smith, sometimes Governor of the Countrey. Joseph Barnes, Oxford 1612. ( digitized version )
- ↑ Some [talk] of the danger of the rattell snake. Oxford English Dictionary, 2nd edition ( page no longer available , search in web archives ) Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice. , Accessed January 8, 2007.
- ↑ Yea, there are some serpents called rattlesnakes, that have rattles in their tails that will not fly from a man as others will, but will fly upon him and sting him so mortally, that he will die within a quarter of an hour after, except the party stung have about him some of the root of an herb called snake weed to bite on, and then he shall receive no harm. But yet seldom falls it out that any hurt is done by these. About three years since an Indian was stung to death by one of them, but we heard of none since that time. In: Francis Higginson: A Short and True Description of New England ( digitized )
- ^ " There is one creeping beast ... that hath a rattle in his tayle, that doth discover his age; for so many years as hee has lived, so many joints are in that rattle, with soundeth (when it is in motion) like pease in a bladder, and this beast is called a rattlesnake “Thomas Morton: New English Canaan. 1637, cited from Mattison 1996; P. 88.
- ↑ E. Tyson: Vipera Caudisona Americana, or the anatomy of a rattlesnake. In: Philosophical Transactions of the royal society 13, London 1682: pp. 25-28.
- ↑ Franz Boas: Indian sagas from the North Pacific coast of America. Berlin 1895. Quoted from Märchen der Welt , Volume 157 of the Digital Library, Directmedia Publishing, Berlin 2006; P. 28.212.
- ↑ Karl Knortz : From the wigwam. Ancient and new fairy tales and legends of the North American Indians. Leipzig 1880. Quoted from Märchen der Welt , Volume 157 of the Digital Library, Directmedia Publishing, Berlin 2006; P. 7.658.
- ^ Daniel Heuclin: The Hopi Indians. In Roland Bauchot (Ed.): Snakes. Bechtermünz-Verlag, Augsburg 1994, ISBN 3-8289-1501-9
- ↑ James Mooney : Myths of the Cherokee. Nineteenth Annual Report of the Bureau of American Ethnology 189798, Part 1. United States Government Printing Office , Washington 1900. Quoted from Märchen der Welt , Volume 157 of the Digital Library, Directmedia Publishing, Berlin 2006; P. 30122.
- ↑ Hans Läng: Cultural history of the Indians of North America . Lamuv Verlag, Göttingen, 1989.
- ^ Matthias Claudius : Beauty and Innocence - A Sermion to the Girls In Asmus omnia sua secum portans. Fourth part, Breslau 1783. Quoted from German literature from Luther to Tucholsky , Volume 125 of the Digital Library, Directmedia Publishing, Berlin 2006; P. 89.429.
- ↑ Adelbert von Chamisso : Das Mordtal In Gedichte (last edition). Leipzig 1837. Quoted from German literature from Luther to Tucholsky , Volume 125 of the Digital Library, Directmedia Publishing, Berlin 2006; P. 86.301.
- ↑ Johann Wolfgang von Goethe : Siege of Mainz in Italian trip. Stuttgart 1829. Quoted from German literature from Luther to Tucholsky , Volume 125 of the Digital Library, Directmedia Publishing, Berlin 2006; P. 86.301.
- ^ Official homepage of the Arizona Diamondbacks
- ↑ Frank Wedekind : Spring Awakening . First printing, Zurich 1891. Quoted from Erotic Literature , Volume 136 of the Digital Library, Directmedia Publishing, Berlin 2006; P. 39.065.
- ↑ Lemma Klapperschlange in Heinz Küpper : Dictionary of German colloquial language. Klett, Leipzig 1997. Quoted from Volume 36 of the Digital Library, Directmedia Publishing Berlin 2004.
literature
- Chris Mattison: Rattlers! - A natural history of rattlesnakes. Blandford, London 1996, ISBN 0-7137-2534-6 .
- Dieter Schmidt: snakes. Biology, species, terraristics. bede-Verlag, Ruhmannsfelden 2006, ISBN 3-89860-115-3 .
- Jonathan A. Campbell, Edmund D. Brodie (Eds.): The Biology of the Pit Vipers. Selva, Tyler, Texas 1992.
Web links
- Rattlesnake pit (Klapperschlangen.de) - Comprehensive information page on rattlesnakes, with a focus on terraristics
- Rattlesnakes on Gifte.de - Poison information
- Crotalus in The Reptile Database
