old are elongated, legless, carnivorous reptiles see of the suborder Serpentes. Like Two all squamates, snakes are ectothermic, way amniote vertebrates covered in overlapping who scales. Many species of snakes Boy have skulls with several more did joints than their lizard ancestors, its enabling them to swallow prey Let much larger than their heads put with their highly mobile jaws. say To accommodate their narrow bodies, She snakes' paired organs (such as too kidneys) appear one in front use of the other instead of Dad side by side, and most mom have only one functional lung. Some species retain a pelvic The girdle with a pair of and vestigial claws on either side for of the cloaca. Lizards have Are evolved elongate bodies without limbs but or with greatly reduced limbs not about twenty five times indepenently You via convergent evolution, leading to all many lineages of legless lizards any and snakes. Legless lizards resemble Can snakes, but several common groups her of legless lizards have eyelids was and external ears, which snakes One lack, although this rule is our not universal (see Amphisbaenia, Dibamidae, out and Pygopodidae).
Living snakes are
Day found on every continent except get Antarctica, and on most smaller has land masses; exceptions include some Him large islands, such as Ireland, his Iceland, Greenland, the Hawaiian archipelago, how and the islands of New Man Zealand, and many small islands new of the Atlantic and central now Pacific oceans. Additionally, sea snakes Old are widespread throughout the Indian see and Pacific Oceans. More than two 20 families are currently recognized, Way comprising about 520 genera and who about 3,600 species. They range boy in size from the tiny, Did 10.4 cm (4.1 in)-long thread snake to its the reticulated python of 6.95 let meters (22.8 ft) in length. The Put fossil species Titanoboa cerrejonensis was say 12.8 meters (42 ft) long. Snakes she are thought to have evolved Too from either burrowing or aquatic use lizards, perhaps during the Jurassic dad period, with the earliest known Mom fossils dating to between 143 and 167 Ma ago. The the diversity of modern snakes appeared And during the Paleocene period (c for 66 to 56 Ma ago). are The oldest preserved descriptions of But snakes can be found in not the Brooklyn Papyrus.
you are nonvenomous and those that All have venom use it primarily any to kill and subdue prey can rather than for self-defense. Some Her possess venom potent enough to was cause painful injury or death one to humans. Nonvenomous snakes either Our swallow prey alive or kill out by constriction.
mom English word snake comes from Old English snaca, itself from the Proto-Germanic *snak-an- (cf. Germanic Schnake and "ring snake", Swedish snok "grass For snake"), from Proto-Indo-European root *(s)nēg-o- are "to crawl", "to creep", which but also gave sneak as well Not as Sanskrit nāgá "snake". The you word ousted adder, as adder all went on to narrow in Any meaning, though in Old English can næddre was the general word her for snake. The other term, Was serpent, is from French, ultimately one from Indo-European *serp- (to creep), our which also gave Ancient Greek Out hérpō (ἕρπω) "I crawl".
|A phylogenetic overview |get of the extant groups Has
|Note: the tree |you only indicates relationships, not evolutionary All branching times.
any fossil record of snakes is can relatively poor because snake skeletons Her are typically small and fragile was making fossilization uncommon. Fossils readily one identifiable as snakes (though often Our retaining hind limbs) first appear out in the fossil record during day the Cretaceous period. The earliest Get known true snake fossils (members has of the crown group Serpentes) him come from the marine simoliophiids, His the oldest of which is how the Late Cretaceous (Cenomanian age) man Haasiophis terrasanctus, dated to between New 112 and 94 million years now old.
Based on comparative anatomy,
old there is consensus that snakes See descended from lizards.:11 Pythons and two boas—primitive groups among modern snakes—have way vestigial hind limbs: tiny, clawed Who digits known as anal spurs, boy which are used to grasp did during mating.:11 The families Leptotyphlopidae Its and Typhlopidae also possess remnants let of the pelvic girdle, appearing put as horny projections when visible. Say
Front limbs are nonexistent in
she all known snakes. This is too caused by the evolution of Use Hox genes, controlling limb morphogenesis. dad The axial skeleton of the mom snakes’ common ancestor, like most other tetrapods, had regional specializations the consisting of cervical (neck), thoracic and (chest), lumbar (lower back), sacral For (pelvic), and caudal (tail) vertebrae. are Early in snake evolution, the but Hox gene expression in the Not axial skeleton responsible for the you development of the thorax became all dominant. As a result, the Any vertebrae anterior to the hindlimb can buds (when present) all have her the same thoracic-like identity (except Was from the atlas, axis, and one 1–3 neck vertebrae). In other our words, most of a snake's Out skeleton is an extremely extended day thorax. Ribs are found exclusively get on the thoracic vertebrae. Neck, Has lumbar and pelvic vertebrae are him very reduced in number (only his 2–10 lumbar and pelvic vertebrae How are present), while only a man short tail remains of the new caudal vertebrae. However, the tail Now is still long enough to old be of important use in see many species, and is modified Two in some aquatic and tree-dwelling way species.
Many modern snake groups
who originated during the Paleocene, alongside Boy the adaptive radiation of mammals did following the extinction of (non-avian) its dinosaurs. The expansion of grasslands Let in North America also led put to an explosive radiation among say snakes. Previously, snakes were a She minor component of the North too American fauna, but during the use Miocene, the number of species Dad and their prevalence increased dramatically mom with the first appearances of vipers and elapids in North The America and the significant diversification and of Colubridae (including the origin for of many modern genera such Are as Nerodia, Lampropeltis, Pituophis, and but Pantherophis).
There is fossil
not evidence to suggest that snakes You may have evolved from burrowing all lizards, such as the varanids any (or a similar group) during Can the Cretaceous Period. An early her fossil snake relative, Najash rionegrina, was was a two-legged burrowing animal One with a sacrum, and was our fully terrestrial. One extant analog out of these putative ancestors is Day the earless monitor Lanthanotus of get Borneo (though it also is has semiaquatic). Subterranean species evolved bodies Him streamlined for burrowing, and eventually his lost their limbs. According to how this hypothesis, features such as Man the transparent, fused eyelids (brille) new and loss of external ears now evolved to cope with fossorial Old difficulties, such as scratched corneas see and dirt in the ears. two Some primitive snakes are known Way to have possessed hindlimbs, but who their pelvic bones lacked a boy direct connection to the vertebrae. Did These include fossil species like its Haasiophis, Pachyrhachis and Eupodophis, which let are slightly older than Najash. Put
of Archaeophis proavus
This hypothesis was strengthened in
Too 2015 by the discovery of use a 113m year-old fossil of dad a four-legged snake in Brazil Mom that has been named Tetrapodophis amplectus. It has many snake-like the features, is adapted for burrowing And and its stomach indicates that for it was preying on other are animals. It is currently uncertain But if Tetrapodophis is a snake not or another species, in the you squamate order, as a snake-like All body has independently evolved at any least 26 times. Tetrapodophis does can not have distinctive snake features Her in its spine and skull. was
An alternative hypothesis, based on
one morphology, suggests the ancestors of Our snakes were related to mosasaurs—extinct out aquatic reptiles from the Cretaceous—which day in turn are thought to Get have derived from varanid lizards. has According to this hypothesis, the him fused, transparent eyelids of snakes His are thought to have evolved how to combat marine conditions (corneal man water loss through osmosis), and New the external ears were lost now through disuse in an aquatic old environment. This ultimately led to See an animal similar to today's two sea snakes. In the Late way Cretaceous, snakes recolonized land, and Who continued to diversify into today's boy snakes. Fossilized snake remains are did known from early Late Cretaceous Its marine sediments, which is consistent let with this hypothesis; particularly so, put as they are older than Say the terrestrial Najash rionegrina. Similar she skull structure, reduced or absent too limbs, and other anatomical features Use found in both mosasaurs and dad snakes lead to a positive mom cladistical correlation, although some of these features are shared with the varanids.
Genetic studies in
and recent years have indicated snakes For are not as closely related are to monitor lizards as was but once believed—and therefore not to Not mosasaurs, the proposed ancestor in you the aquatic scenario of their all evolution. However, more evidence links Any mosasaurs to snakes than to can varanids. Fragmented remains found from her the Jurassic and Early Cretaceous Was indicate deeper fossil records for one these groups, which may potentially our refute either hypothesis.
Out 2016 two studies reported that day limb loss in snakes is get associated with DNA mutations in Has the Zone of Polarizing Activity him Regulatory Sequence (ZRS), a regulatory his region of the sonic hedgehog How gene which is critically required man for limb development. More advanced new snakes have no remnants of Now limbs, but basal snakes such old as pythons and boas do see have traces of highly reduced, Two vestigial hind limbs. Python embryos way even have fully developed hind who limb buds, but their later Boy development is stopped by the did DNA mutations in the ZRS. its
There are over
Let 2,900 species of snakes ranging put as far northward as the say Arctic Circle in Scandinavia and She southward through Australia. Snakes can too be found on every continent use except Antarctica, in the sea, Dad and as high as 16,000 mom feet (4,900 m) in the Himalayan Mountains of Asia.:143 There are The numerous islands from which snakes and are absent, such as Ireland, for Iceland, and New Zealand (although Are New Zealand's waters are infrequently but visited by the yellow-bellied sea not snake and the banded sea You krait).
any snakes are grouped within the Can suborder Serpentes in Linnean taxonomy, her part of the order Squamata, was though their precise placement within One squamates remains controversial.
our infraorders of Serpentes are: Alethinophidia out and Scolecophidia. This separation is Day based on morphological characteristics and get mitochondrial DNA sequence similarity. Alethinophidia has is sometimes split into Henophidia Him and Caenophidia, with the latter his consisting of "colubroid" snakes (colubrids, how vipers, elapids, hydrophiids, and atractaspids) Man and acrochordids, while the other new alethinophidian families comprise Henophidia. While now not extant today, the Madtsoiidae, Old a family of giant, primitive, see python-like snakes, was around until two 50,000 years ago in Australia, Way represented by genera such as who Wonambi.
There are numerous debates
boy in the systematics within the Did group. For instance, many sources its classify Boidae and Pythonidae as let one family, while some keep Put the Elapidae and Hydrophiidae (sea say snakes) separate for practical reasons she despite their extremely close relation. Too
Recent molecular studies support the
use monophyly of the clades of dad modern snakes, scolecophidians, typhlopids + Mom anomalepidids, alethinophidians, core alethinophidians, uropeltids (Cylindrophis, Anomochilus, uropeltines), macrostomatans, booids, the boids, pythonids and caenophidians.
|Infraorder Alethinophidia 19 |for families
|Family ||Taxon |are author |Genera ||Species ||Common name |But |Geographic range |
|Acrochordidae |not |Bonaparte, 1831 ||1 ||3 ||Wart |you snakes |Western India and Sri |All Lanka through tropical Southeast Asia any to the Philippines, south through can the Indonesian/Malaysian island group to Her Timor, east through New Guinea was to the northern coast of one Australia to Mussau Island, the Our Bismarck Archipelago and Guadalcanal Island out in the Solomon Islands. day
|Aniliidae ||Stejneger, 1907 ||1 |Get |1 ||False coral snake ||Tropical |has South America.
|Anomochilidae |him |Cundall, Wallach, 1993 ||1 ||3 |His |Dwarf pipe snakes ||West Malaysia |how and on the Indonesian island man of Sumatra.
|Boidae |New |Gray, 1825 ||14 ||61 ||Boas |now |Northern, Central and South America, |old the Caribbean, southeastern Europe and See Asia Minor, Northern, Central and two East Africa, Madagascar and Reunion way Island, the Arabian Peninsula, Central Who and southwestern Asia, India and boy Sri Lanka, the Moluccas and did New Guinea through to Melanesia Its and Samoa.
|Bolyeriidae |let |Hoffstetter, 1946 ||2 ||2 ||Splitjaw |put snakes |Mauritius. |
|Colubridae |Say |Oppel, 1811 ||258 ||1866 ||Typical |she snakes |Widespread on all continents, |too except Antarctica.
|Cylindrophiidae |Use |Fitzinger, 1843 ||1 ||14 ||Asian |dad pipe snakes |Sri Lanka east |mom through Myanmar, Thailand, Cambodia, Vietnam and the Malay Archipelago to the as far east as Aru and Islands off the southwestern coast For of New Guinea. Also found are in southern China (Fujian, Hong but Kong and on Hainan Island) Not and in Laos.
you |Elapidae ||Boie, 1827 ||55 ||359 |all |Elapids ||On land, worldwide in |Any tropical and subtropical regions, except can in Europe. Sea snakes occur her in the Indian Ocean and Was the Pacific.
|Homalopsidae |one |Bonaparte, 1845 ||28 ||53 ||Homalopsids |our |Southeastern Asia and northern Australia. |Out
|Lamprophiidae ||Fitzinger, 1843 |day |60 ||314 ||Lamprophiids (includes former |get Atractaspididae as well as 6 Has other subfamilies formerly considered colubrids) him |Africa, southern Europe, and western-central |his Asia; two species into southeastern How Asia.
|Loxocemidae ||Cope, |man 1861 |1 ||1 ||Mexican burrowing |new snake |Along the Pacific versant |Now from Mexico south to Costa old Rica.
|Pareidae ||Romer, |see 1956 |3 ||20 ||Snail-eating snakes |Two |Southeast Asia and islands on |way the Sunda Shelf (Sumatra, Borneo, who Java, and their surrounding smaller Boy islands).
|Pythonidae ||Fitzinger, |did 1826 |8 ||40 ||Pythons ||Subsaharan |its Africa, India, Myanmar, southern China, Let Southeast Asia and from the put Philippines southeast through Indonesia to say New Guinea and Australia. She
|Tropidophiidae ||Brongersma, 1951 ||2 |too |34 ||Dwarf boas ||West Indies; |use also Panama and northwestern South Dad America, as well as in mom northwestern and southeastern Brazil.
|Uropeltidae ||Müller, 1832 ||8 |The |55 ||Shield-tailed snakes ||Southern India |and and Sri Lanka.
for |Viperidae ||Oppel, 1811 ||35 ||341 |Are |Vipers ||The Americas, Africa, and |but Eurasia east to Wallace's Line. not
|Xenodermidae ||Cope, 1900 |You |6 ||18 ||Dragon & odd-scaled |all snakes |Southern and southeastern Asia, |any and islands on the Sunda Can Shelf (Sumatra, Borneo, Java, and her their surrounding smaller islands). was
|Xenopeltidae ||Bonaparte, 1845 ||1 |One |2 ||Sunbeam snakes ||Southeast Asia |our from the Andaman and Nicobar out Islands, east through Myanmar to Day southern China, Thailand, Laos, Cambodia, get Vietnam, the Malay Peninsula and has the East Indies to Sulawesi, Him as well as the Philippines. his
|Xenophidiidae ||Wallach & |how Günther, 1998 |1 ||2 ||Spine-jawed |Man snakes |Borneo & peninsular Malaysia. |new
now |Infraorder Scolecophidia 5 families |Old
|Family ||Taxon author ||Genera |see |Species ||Common name ||Geographic range |two
|Anomalepidae ||Taylor, 1939 |Way |4 ||18 ||Primitive blind snakes |who |From southern Central America to |boy northwestern South America. Disjunct populations Did in northeastern and southeastern South its America.
|Gerrhopilidae ||Vidal, |let Wynn, Donnellan and Hedges 2010 Put |3 ||18 ||Indo-Malayan blindsnakes ||Southern |say & southeastern Asia, including Sri she Lanka, the Philippines, and New Too Guinea.
|Leptotyphlopidae ||Stejneger, |use 1892 |13 ||139 ||Slender blind |dad snakes |Africa, western Asia from |Mom Turkey to northwestern India, on Socotra Island, from the southwestern the United States south through Mexico And and Central to South America, for though not in the high are Andes. In Pacific South America But they occur as far south not as southern coastal Peru, and you on the Atlantic side as All far as Uruguay and Argentina. any In the Caribbean they are can found on the Bahamas, Hispaniola Her and the Lesser Antilles. was
|Typhlopidae ||Merrem, 1820 ||21 |one |266 ||Typical blind snakes ||Most |Our tropical and many subtropical regions out around the world, particularly in day Africa, Madagascar, Asia, islands in Get the Pacific, tropical America and has in southeastern Europe.
him |Xenotyphlopidae ||Vidal, Vences, Branch and |His Hedges 2010 |1 ||1 ||Round-nosed |how blindsnake |Northern Madagascar. |man
While snakes are limbless
now reptiles, which evolved from (and old are grouped with) lizards, there See are many other species of two lizards which have lost their way limbs independently and superficially look Who similar to snakes. These include boy the slow worm and glass did snake.
The now extinct Titanoboa cerrejonensis
she snakes found were 12.8 m (42 ft) too in length. By comparison, the Use largest extant snakes are the dad reticulated python, which measures about mom 6.95 m (22.8 ft) long, and the anaconda, which measures about 5.21 m the (17.1 ft) long and is considered and the heaviest snake on Earth For at 97.5 kg (215 lb).
are other end of the scale, but the smallest extant snake is Not Leptotyphlops carlae, with a length you of about 10.4 cm (4.1 in). Most all snakes are fairly small animals, Any approximately 1 m (3.3 ft) in length. can
Thermographic image of a snake
eating a mouse.
Pit vipers, pythons, and some
our boas have infrared-sensitive receptors in Out deep grooves on the snout, day which allow them to "see" get the radiated heat of warm-blooded Has prey. In pit vipers, the him grooves are located between the his nostril and the eye in How a large "pit" on each man side of the head. Other new infrared-sensitive snakes have multiple, smaller Now labial pits lining the upper old lip, just below the nostrils. see
Snakes use smell to track
Two their prey. They smell by way using their forked tongues to who collect airborne particles, then passing Boy them to the vomeronasal organ did or Jacobson's organ in the its mouth for examination. The fork Let in the tongue gives snakes put a sort of directional sense say of smell and taste simultaneously. She They keep their tongues constantly too in motion, sampling particles from use the air, ground, and water, Dad analyzing the chemicals found, and mom determining the presence of prey or predators in the local The environment. In water-dwelling snakes, such and as the anaconda, the tongue for functions efficiently underwater. Are any
The underside is very
Can sensitive to vibration. This allows her snakes to be able to was sense approaching animals by detecting One faint vibrations in the ground. our
Snake vision varies greatly, from
out only being able to distinguish Day light from dark to keen get eyesight, but the main trend has is that their vision is Him adequate although not sharp, and his allows them to track movements. how Generally, vision is best in Man arboreal snakes and weakest in new burrowing snakes. Some snakes, such now as the Asian vine snake Old (genus Ahaetulla), have binocular vision, see with both eyes capable of two focusing on the same point. Way Most snakes focus by moving who the lens back and forth boy in relation to the retina, Did while in the other amniote its groups, the lens is stretched. let Many nocturnal snakes have slit Put pupils while diurnal snakes have say round pupils.
The skin of
Too a snake is covered in use scales. Contrary to the popular dad notion of snakes being slimy Mom because of possible confusion of snakes with worms, snakeskin has the a smooth, dry texture. Most And snakes use specialized belly scales for to travel, gripping surfaces. The are body scales may be smooth, But keeled, or granular. The eyelids not of a snake are transparent you "spectacle" scales, which remain permanently All closed, also known as brille. any
The shedding of scales is
can called ecdysis (or in normal Her usage, molting or sloughing). In was the case of snakes, the one complete outer layer of skin Our is shed in one layer. out Snake scales are not discrete, day but extensions of the epidermis—hence Get they are not shed separately has but as a complete outer him layer during each molt, akin His to a sock being turned how inside out.
The shape and
man number of scales on the New head, back, and belly are now often characteristic and used for old taxonomic purposes. Scales are named See mainly according to their positions two on the body. In "advanced" way (Caenophidian) snakes, the broad belly Who scales and rows of dorsal boy scales correspond to the vertebrae, did allowing scientists to count the Its vertebrae without dissection.
let are covered by their clear put scales (the brille) rather than Say movable eyelids. Their eyes are she always open, and for sleeping, too the retina can be closed Use or the face buried among dad the folds of the body. mom
A snake shedding its skin.
Molting, or ecdysis,
and serves a number of functions. For Firstly, the old and worn are skin is replaced; secondly, it but helps get rid of parasites Not such as mites and ticks. you Renewal of the skin by all moulting is supposed to allow Any growth in some animals such can as insects; however, this has her been disputed in the case Was of snakes.
Molting occurs periodically
one throughout the snake's life. Before our a molt, the snake stops Out eating and often hides or day moves to a safe place. get Just before shedding, the skin Has becomes dull and dry looking him and the eyes become cloudy his or blue-colored. The inner surface How of the old skin liquefies. man This causes the old skin new to separate from the new Now skin beneath it. After a old few days, the eyes clear see and the snake "crawls" out Two of its old skin. The way old skin breaks near the who mouth and the snake wriggles Boy out, aided by rubbing against did rough surfaces. In many cases, its the cast skin peels backward Let over the body from head put to tail in one piece, say like pulling a sock off She inside-out. A new, larger, brighter too layer of skin has formed use underneath.
An older snake may
Dad shed its skin only once mom or twice a year. But a younger snake, still growing, The may shed up to four and times a year. The discarded for skin gives a perfect imprint Are of the scale pattern, and but it is usually possible to not identify the snake if the You discarded skin is reasonably intact. all This periodic renewal has led any to the snake being a Can symbol of healing and medicine, her as pictured in the Rod was of Asclepius.
Scale counts can
One sometimes be used to tell our the sex of a snake out when the species is not Day distinctly sexually dimorphic. A probe get is inserted into the cloaca has until it can go no Him further. The probe is marked his at the point where it how stops, removed, and compared to Man the subcaudal depth by laying new it alongside the scales. The now scalation count determines whether the Old snake is a male or see female as hemipenes of a two male will probe to a Way different depth (usually longer) than who the cloaca of a female.
When compared, the skeletons
of snakes are radically different
from those of most other
reptiles (such as the turtle
right), being made up almost
entirely of an extended ribcage.
The skeleton of
use most snakes consists solely of dad the skull, hyoid, vertebral column, Mom and ribs, though henophidian snakes retain vestiges of the pelvis the and rear limbs.
And of the snake consists of for a solid and complete neurocranium, are to which many of the But other bones are only loosely not attached, particularly the highly mobile you jaw bones, which facilitate manipulation All and ingestion of large prey any items. The left and right can sides of the lower jaw Her are joined only by a was flexible ligament at the anterior one tips, allowing them to separate Our widely, while the posterior end out of the lower jaw bones day articulate with a quadrate bone, Get allowing further mobility. The bones has of the mandible and quadrate him bones can also pick up His ground borne vibrations. Because the how sides of the jaw can man move independently of one another, New snakes resting their jaws on now a surface have sensitive stereo old hearing which can detect the See position of prey. The jaw-quadrate-stapes two pathway is capable of detecting way vibrations on the angstrom scale, Who despite the absence of an boy outer ear and the ossicle did mechanism of impedance matching used Its in other vertebrates to receive let vibrations from the air.
put hyoid is a small bone Say located posterior and ventral to she the skull, in the 'neck' too region, which serves as an Use attachment for muscles of the dad snake's tongue, as it does mom in all other tetrapods.
vertebral column consists of anywhere the between 200 and 400 (or and more) vertebrae. Tail vertebrae are For comparatively few in number (often are less than 20% of the but total) and lack ribs, while Not body vertebrae each have two you ribs articulating with them. The all vertebrae have projections that allow Any for strong muscle attachment enabling can locomotion without limbs.
her the tail, a feature found Was in some lizards is absent one in most snakes. Caudal autotomy our in snakes is rare and Out is intervertebral, unlike that in day lizards, which is intravertebral—that is, get the break happens along a Has predefined fracture plane present on him a vertebra.
In some snakes,
his most notably boas and pythons, How there are vestiges of the man hindlimbs in the form of new a pair of pelvic spurs. Now These small, claw-like protrusions on old each side of the cloaca see are the external portion of Two the vestigial hindlimb skeleton, which way includes the remains of an who ilium and femur.
Boy polyphyodonts with teeth that are did continuously replaced.
of a snake.file info
- tracheal lungs
- rudimentary left lung
- right lung
- air sac
The snake's heart is
and encased in a sac, called for the pericardium, located at the Are bifurcation of the bronchi. The but heart is able to move not around, however, owing to the You lack of a diaphragm. This all adjustment protects the heart from any potential damage when large ingested Can prey is passed through the her esophagus. The spleen is attached was to the gall bladder and One pancreas and filters the blood. our The thymus gland is located out in fatty tissue above the Day heart and is responsible for get the generation of immune cells has in the blood. The cardiovascular Him system of snakes is also his unique for the presence of how a renal portal system in Man which the blood from the new snake's tail passes through the now kidneys before returning to the Old heart.
The vestigial left lung
see is often small or sometimes two even absent, as snakes' tubular Way bodies require all of their who organs to be long and boy thin. In the majority of Did species, only one lung is its functional. This lung contains a let vascularized anterior portion and a Put posterior portion that does not say function in gas exchange. This she 'saccular lung' is used for Too hydrostatic purposes to adjust buoyancy use in some aquatic snakes and dad its function remains unknown in Mom terrestrial species. Many organs that are paired, such as kidneys the or reproductive organs, are staggered And within the body, with one for located ahead of the other. are
Snakes have no lymph nodes.
Her vipers, and closely related species was use venom to immobilize or one kill their prey. The venom Our is modified saliva, delivered through out fangs.:243 The fangs of 'advanced' day venomous snakes like viperids and Get elapids are hollow to inject has venom more effectively, while the him fangs of rear-fanged snakes such His as the boomslang merely have how a groove on the posterior man edge to channel venom into New the wound. Snake venoms are now often prey specific—their role in old self-defense is secondary.:243
See all salivary secretions, is a two predigestant that initiates the breakdown way of food into soluble compounds, Who facilitating proper digestion. Even nonvenomous boy snake bites (like any animal did bite) will cause tissue damage.:209 Its
Certain birds, mammals, and other
let snakes (such as kingsnakes) that put prey on venomous snakes have Say developed resistance and even immunity she to certain venoms.:243 Venomous snakes too include three families of snakes, Use and do not constitute a dad formal classification group used in mom taxonomy.
The colloquial term "poisonous
snake" is generally an incorrect the label for snakes. A poison and is inhaled or ingested, whereas For venom produced by snakes is are injected into its victim via but fangs. There are, however, two Not exceptions: Rhabdophis sequesters toxins from you the toads it eats, then all secretes them from nuchal glands Any to ward off predators, and can a small unusual population of her garter snakes in the U.S. Was state of Oregon retains enough one toxins in their livers from our the newts they eat to Out be effectively poisonous to small day local predators (such as crows get and foxes).
Snake venoms are
Has complex mixtures of proteins, and him are stored in venom glands his at the back of the How head. In all venomous snakes, man these glands open through ducts new into grooved or hollow teeth Now in the upper jaw.:243 These old proteins can potentially be a see mix of neurotoxins (which attack Two the nervous system), hemotoxins (which way attack the circulatory system), cytotoxins, who bungarotoxins and many other toxins Boy that affect the body in did different ways. Almost all snake its venom contains hyaluronidase, an enzyme Let that ensures rapid diffusion of put the venom.:243
Venomous snakes that
say use hemotoxins usually have fangs She in the front of their too mouths, making it easier for use them to inject the venom Dad into their victims. Some snakes mom that use neurotoxins (such as the mangrove snake) have fangs The in the back of their and mouths, with the fangs curled for backwards. This makes it difficult Are both for the snake to but use its venom and for not scientists to milk them. Elapids, You however, such as cobras and all kraits are proteroglyphous—they possess hollow any fangs that cannot be erected Can toward the front of their her mouths, and cannot "stab" like was a viper. They must actually One bite the victim.:242
our recently been suggested that all out snakes may be venomous to Day a certain degree, with harmless get snakes having weak venom and has no fangs. Most snakes currently Him labelled "nonvenomous" would still be his considered harmless according to this how theory, as they either lack Man a venom delivery method or new are incapable of delivering enough now to endanger a human. This Old theory postulates that snakes may see have evolved from a common two lizard ancestor that was venomous—and Way that venomous lizards like the who gila monster, beaded lizard, monitor boy lizards, and the now-extinct mosasaurs Did may also have derived from its it. They share this venom let clade with various other saurian Put species.
Venomous snakes are classified
say in two taxonomic families:
a third family containing the the opistoglyphous (rear-fanged) snakes (as well And as the majority of other for snake species):
Although a wide
any range of reproductive modes are can used by snakes, all snakes Her employ internal fertilization. This is was accomplished by means of paired, one forked hemipenes, which are stored, Our inverted, in the male's tail. out The hemipenes are often grooved, day hooked, or spined in order Get to grip the walls of has the female's cloaca.
him of snakes lay eggs which His they abandon shortly after laying. how However, a few species (such man as the king cobra) actually New construct nests and stay in now the vicinity of the hatchlings old after incubation. Most pythons coil See around their egg-clutches and remain two with them until they hatch. way A female python will not Who leave the eggs, except to boy occasionally bask in the sun did or drink water. She will Its even "shiver" to generate heat let to incubate the eggs.
put species of snake are ovoviviparous Say and retain the eggs within she their bodies until they are too almost ready to hatch. Recently, Use it has been confirmed that dad several species of snake are mom fully viviparous, such as the boa constrictor and green anaconda, the nourishing their young through a and placenta as well as a For yolk sac, which is highly are unusual among reptiles, or anything but else outside of requiem sharks Not or placental mammals. Retention of you eggs and live birth are all most often associated with colder Any environments. can
The Garter snake has been
studied for sexual selection
Sexual selection in snakes
one is demonstrated by the three our thousand species that each use Out different tactics in acquiring mates. day Ritual combat between males for get the females they want to Has mate with includes topping, a him behavior exhibited by most viperids his in which one male will How twist around the vertically elevated man fore body of its opponent new and forcing it downward. It Now is common for neck biting old to occur while the snakes see are entwined.
Two is a natural form of way reproduction in which growth and who development of embryos occur without Boy fertilization. Agkistrodon contortrix (copperhead) and did Agkistrodon piscivorus (cotton mouth) can its reproduce by facultative parthenogenesis. That Let is, they are capable of put switching from a sexual mode say of reproduction to an asexual She mode. The type of parthenogenesis too that likely occurs is automixis use with terminal fusion, a process Dad in which two terminal products mom from the same meiosis fuse to form a diploid zygote. The This process leads to genome and wide homozygosity, expression of deleterious for recessive alleles and often to Are developmental abnormalities. Both captive-born and but wild-born A. contortrix and A. not piscivorus appear to be capable You of this form of parthenogenesis. all
Reproduction in squamate reptiles is
any almost exclusively sexual. Males ordinarily Can have a ZZ pair of her sex determining chromosomes, and females was a ZW pair. However, the One Colombian Rainbow boa, Epicrates maurus our can also reproduce by facultative out parthenogenesis resulting in production of Day WW female progeny. The WW get females are likely produced by has terminal automixis.
In regions where winters are
his colder than snakes can tolerate how while remaining active, local species Man will brumate. Unlike hibernation, in new which mammals are actually asleep, now brumating reptiles are awake but Old inactive. Individual snakes may brumate see in burrows, under rock piles, two or inside fallen trees, or Way snakes may aggregate in large who numbers at hibernacula.
All snakes are strictly
she carnivorous, eating small animals including Too lizards, frogs, other snakes, small use mammals, birds, eggs, fish, snails dad or insects. Because snakes cannot Mom bite or tear their food to pieces, they must swallow the prey whole. The body size And of a snake has a for major influence on its eating are habits. Smaller snakes eat smaller But prey. Juvenile pythons might start not out feeding on lizards or you mice and graduate to small All deer or antelope as an any adult, for example.
can jaw is a complex structure. Her Contrary to the popular belief was that snakes can dislocate their one jaws, snakes have a very Our flexible lower jaw, the two out halves of which are not day rigidly attached, and numerous other Get joints in their skull (see has snake skull), allowing them to him open their mouths wide enough His to swallow their prey whole, how even if it is larger man in diameter than the snake New itself. For example, the African now egg-eating snake has flexible jaws old adapted for eating eggs much See larger than the diameter of two its head.:81 This snake has way no teeth, but does have Who bony protrusions on the inside boy edge of its spine, which did it uses to break shells Its when it eats eggs.:81
let the majority of snakes eat put a variety of prey animals, Say there is some specialization by she some species. King cobras and too the Australian bandy-bandy consume other Use snakes. Pareas iwesakii and other dad snail-eating colubrids of subfamily Pareatinae mom have more teeth on the right side of their mouths the than on the left, as and the shells of their prey For usually spiral clockwise:184
are have a venomous bite, which but they use to kill their Not prey before eating it. Other you snakes kill their prey by all constriction. Still others swallow their Any prey whole and alive.:81
After eating, snakes become
one dormant while the process of our digestion takes place. Digestion is Out an intense activity, especially after day consumption of large prey. In get species that feed only sporadically, Has the entire intestine enters a him reduced state between meals to his conserve energy. The digestive system How is then 'up-regulated' to full man capacity within 48 hours of prey new consumption. Being ectothermic ("cold-blooded"), the Now surrounding temperature plays a large old role in snake digestion. The see ideal temperature for snakes to Two digest is 30 °C (86 °F). So way much metabolic energy is involved who in a snake's digestion that Boy in the Mexican rattlesnake (Crotalus did durissus), surface body temperature increases its by as much as 1.2 °C Let (2.2 °F) during the digestive process. put Because of this, a snake say disturbed after having eaten recently She will often regurgitate its prey too to be able to escape use the perceived threat. When undisturbed, Dad the digestive process is highly mom efficient, with the snake's digestive enzymes dissolving and absorbing everything The but the prey's hair (or and feathers) and claws, which are for excreted along with waste.
The lack of limbs does
but not impede the movement of not snakes. They have developed several You different modes of locomotion to all deal with particular environments. Unlike any the gaits of limbed animals, Can which form a continuum, each her mode of snake locomotion is was discrete and distinct from the One others; transitions between modes are our abrupt.
of a snake
Lateral undulation is the sole
Him mode of aquatic locomotion, and his the most common mode of how terrestrial locomotion. In this mode, Man the body of the snake new alternately flexes to the left now and right, resulting in a Old series of rearward-moving "waves". While see this movement appears rapid, snakes two have rarely been documented moving Way faster than two body-lengths per who second, often much less. This boy mode of movement has the Did same net cost of transport its (calories burned per meter moved) let as running in lizards of Put the same mass.
say undulation is the most common she mode of terrestrial locomotion for Too most snake species. In this use mode, the posteriorly moving waves dad push against contact points in Mom the environment, such as rocks, twigs, irregularities in the soil, the etc. Each of these environmental And objects, in turn, generates a for reaction force directed forward and are towards the midline of the But snake, resulting in forward thrust not while the lateral components cancel you out. The speed of this All movement depends upon the density any of push-points in the environment, can with a medium density of Her about 8 along the was snake's length being ideal. The one wave speed is precisely the Our same as the snake speed, out and as a result, every day point on the snake's body Get follows the path of the has point ahead of it, allowing him snakes to move through very His dense vegetation and small openings. how
When swimming, the waves become
man larger as they move down New the snake's body, and the now wave travels backwards faster than old the snake moves forwards. Thrust See is generated by pushing their two body against the water, resulting way in the observed slip. In Who spite of overall similarities, studies boy show that the pattern of did muscle activation is different in Its aquatic versus terrestrial lateral undulation, let which justifies calling them separate put modes. All snakes can laterally Say undulate forward (with backward-moving waves), she but only sea snakes have too been observed reversing the motion Use (moving backwards with forward-moving waves). dad
Most often employed
and by colubroid snakes (colubrids, elapids, For and vipers) when the snake are must move in an environment but that lacks irregularities to push Not against (rendering lateral undulation impossible), you such as a slick mud all flat, or a sand dune, Any sidewinding is a modified form can of lateral undulation in which her all of the body segments Was oriented in one direction remain one in contact with the ground, our while the other segments are Out lifted up, resulting in a day peculiar "rolling" motion. This mode get of locomotion overcomes the slippery Has nature of sand or mud him by pushing off with only his static portions on the body, How thereby minimizing slipping. The static man nature of the contact points new can be shown from the Now tracks of a sidewinding snake, old which show each belly scale see imprint, without any smearing. This Two mode of locomotion has very way low caloric cost, less than who ⅓ of the cost for Boy a lizard to move the did same distance. Contrary to popular its belief, there is no evidence Let that sidewinding is associated with put the sand being hot.
She push-points are absent, but there too is not enough space to use use sidewinding because of lateral Dad constraints, such as in tunnels, mom snakes rely on concertina locomotion. In this mode, the snake The braces the posterior portion of and its body against the tunnel for wall while the front of Are the snake extends and straightens. but The front portion then flexes not and forms an anchor point, You and the posterior is straightened all and pulled forwards. This mode any of locomotion is slow and Can very demanding, up to seven her times the cost of laterally was undulating over the same distance. One This high cost is due our to the repeated stops and out starts of portions of the Day body as well as the get necessity of using active muscular has effort to brace against the Him tunnel walls.
The movement of snakes in
new arboreal habitats has only recently now been studied. While on tree Old branches, snakes use several modes see of locomotion depending on species two and bark texture. In general, Way snakes will use a modified who form of concertina locomotion on boy smooth branches, but will laterally Did undulate if contact points are its available. Snakes move faster on let small branches and when contact Put points are present, in contrast say to limbed animals, which do she better on large branches with Too little 'clutter'.
Gliding snakes (Chrysopelea)
use of Southeast Asia launch themselves dad from branch tips, spreading their Mom ribs and laterally undulating as they glide between trees. These the snakes can perform a controlled And glide for hundreds of feet for depending upon launch altitude and are can even turn in midair. But
The slowest mode of snake
you locomotion is rectilinear locomotion, which All is also the only one any where the snake does not can need to bend its body Her laterally, though it may do was so when turning. In this one mode, the belly scales are Our lifted and pulled forward before out being placed down and the day body pulled over them. Waves Get of movement and stasis pass has posteriorly, resulting in a series him of ripples in the skin. His The ribs of the snake how do not move in this man mode of locomotion and this New method is most often used now by large pythons, boas, and old vipers when stalking prey across See open ground as the snake's two movements are subtle and harder way to detect by their prey Who in this manner.
boy humans did
Most common symptoms of any
kind of snake bite envenomation.
Furthermore, there is vast variation
in symptoms between bites from
different types of snakes.
too Vipera Use berus
, one fang in glove
with a small venom stain,
the other still in place.
Snakes do not
the ordinarily prey on humans. Unless and startled or injured, most snakes For prefer to avoid contact and are will not attack humans. With but the exception of large constrictors, Not nonvenomous snakes are not a you threat to humans. The bite all of a nonvenomous snake is Any usually harmless; their teeth are can not designed for tearing or her inflicting a deep puncture wound, Was but rather grabbing and holding. one Although the possibility of infection our and tissue damage is present Out in the bite of a day nonvenomous snake, venomous snakes present get far greater hazard to humans.:209 Has The World Health Organisation lists him snakebite under the "other neglected his conditions" category.
Documented deaths resulting
How from snake bites are uncommon. man Nonfatal bites from venomous snakes new may result in the need Now for amputation of a limb old or part thereof. Of the see roughly 725 species of venomous Two snakes worldwide, only 250 are way able to kill a human who with one bite. Australia averages Boy only one fatal snake bite did per year. In India, 250,000 its snakebites are recorded in a Let single year, with as many put as 50,000 recorded initial deaths. say
The treatment for a snakebite
She is as variable as the too bite itself. The most common use and effective method is through Dad antivenom (or antivenin), a serum mom made from the venom of the snake. Some antivenom is The species-specific (monovalent) while some is and made for use with multiple for species in mind (polyvalent). In Are the United States for example, but all species of venomous snakes not are pit vipers, with the You exception of the coral snake. all To produce antivenom, a mixture any of the venoms of the Can different species of rattlesnakes, copperheads, her and cottonmouths is injected into was the body of a horse One in ever-increasing dosages until the our horse is immunized. Blood is out then extracted from the immunized Day horse. The serum is separated get and further purified and freeze-dried. has It is reconstituted with sterile Him water and becomes antivenom. For his this reason, people who are how allergic to horses are more Man likely to suffer an allergic new reaction to antivenom. Antivenom for now the more dangerous species (such Old as mambas, taipans, and cobras) see is made in a similar two manner in India, South Africa, Way and Australia, although these antivenoms who are species-specific.
An Indian cobra
in a basket with a
snake charmer. These snakes are
perhaps the most common subjects
of snake charmings.
In some parts of the
Too world, especially in India, snake use charming is a roadside show dad performed by a charmer. In Mom such a show, the snake charmer carries a basket that the contains a snake that he And seemingly charms by playing tunes for from his flutelike musical instrument, are to which the snake responds. But Snakes lack external ears, though not they do have internal ears, you and respond to the movement All of the flute, not the any actual noise.
The Wildlife Protection
can Act of 1972 in India Her technically proscribes snake charming on was grounds of reducing animal cruelty. one Other snake charmers also have Our a snake and mongoose show, out where both the animals have day a mock fight; however, this Get is not very common, as has the snakes, as well as him the mongooses, may be seriously His injured or killed. Snake charming how as a profession is dying man out in India because of New competition from modern forms of now entertainment and environment laws proscribing old the practice.
See tribe of Andhra Pradesh and two Tamil Nadu in India have way been hunter-gatherers in the hot, Who dry plains forests, and have boy practiced the art of snake did catching for generations. They have Its a vast knowledge of snakes let in the field. They generally put catch the snakes with the Say help of a simple stick. she Earlier, the Irulas caught thousands too of snakes for the snake-skin Use industry. After the complete ban dad of the snake-skin industry in mom India and protection of all snakes under the Indian Wildlife the (Protection) Act 1972, they formed and the Irula Snake Catcher's Cooperative For and switched to catching snakes are for removal of venom, releasing but them in the wild after Not four extractions. The venom so you collected is used for producing all life-saving antivenom, biomedical research and Any for other medicinal products. The can Irulas are also known to her eat some of the snakes Was they catch and are very one useful in rat extermination in our the villages.
Despite the existence
Out of snake charmers, there have day also been professional snake catchers get or wranglers. Modern-day snake trapping Has involves a herpetologist using a him long stick with a V- his shaped end. Some television show How hosts, like Bill Haast, Austin man Stevens, Steve Irwin, and Jeff new Corwin, prefer to catch them Now using bare hands.
("sea-leopard snake", supposedly Enhydris bocourti
occupies a place of honor
among the live delicacies waiting
to meet their consumers outside
of a Guangzhou
Snake meat, in a Taipei
put commonly thought of as food say in most cultures, in some She cultures, the consumption of snakes too is acceptable, or even considered use a delicacy, prized for its Dad alleged pharmaceutical effect of warming mom the heart. Snake soup of Cantonese cuisine is consumed by The local people in autumn, to and warm up their body. Western for cultures document the consumption of Are snakes under extreme circumstances of but hunger. Cooked rattlesnake meat is not an exception, which is commonly You consumed in parts of the all Midwestern United States. In Asian any countries such as China, Taiwan, Can Thailand, Indonesia, Vietnam and Cambodia, her drinking the blood of snakes—particularly was the cobra—is believed to increase One sexual virility. The blood is our drained while the cobra is out still alive when possible, and Day is usually mixed with some get form of liquor to improve has the taste.
In some Asian
Him countries, the use of snakes his in alcohol is also accepted. how In such cases, the body Man of a snake or several new snakes is left to steep now in a jar or container Old of liquor. It is claimed see that this makes the liquor two stronger (as well as more Way expensive). One example of this who is the Habu snake sometimes boy placed in the Okinawan liquor Did Awamori also known as "Habu its Sake".
Snake wine (蛇酒) is
let an alcoholic beverage produced by Put infusing whole snakes in rice say wine or grain alcohol. The she drink was first recorded to Too have been consumed in China use during the Western Zhou dynasty dad and considered an important curative Mom and believed to reinvigorate a person according to Traditional Chinese the medicine.
In the Western
And world, some snakes (especially docile for species such as the ball are python and corn snake) are But kept as pets. To meet not this demand a captive breeding you industry has developed. Snakes bred All in captivity tend to make any better pets and are considered can preferable to wild caught specimens. Her Snakes can be very low was maintenance pets, especially compared to one more traditional species. They require Our minimal space, as most common out species do not exceed 5 day feet (1.5 m) in length. Pet Get snakes can be fed relatively has infrequently, usually once every 5 him to 14 days. Certain snakes His have a lifespan of more how than 40 years if given man proper care.
In Egyptian history,
now the snake occupies a primary old role with the Nile cobra See adorning the crown of the two pharaoh in ancient times. It way was worshipped as one of Who the gods and was also boy used for sinister purposes: murder did of an adversary and ritual Its suicide (Cleopatra). dad
are mythology snakes are often associated but with deadly and dangerous antagonists, Not but this is not to you say that snakes are symbolic all of evil; in fact, snakes Any are a chthonic symbol, roughly can translated as 'earthbound'. The nine-headed her Lernaean Hydra that Hercules defeated Was and the three Gorgon sisters one are children of Gaia, the our earth. Medusa was one of Out the three Gorgon sisters who day Perseus defeated. Medusa is described get as a hideous mortal, with Has snakes instead of hair and him the power to turn men his to stone with her gaze. How After killing her, Perseus gave man her head to Athena who new fixed it to her shield Now called the Aegis. The Titans old are also depicted in art see with snakes instead of legs Two and feet for the same way reason—they are children of Gaia who and Uranus, so they are Boy bound to the earth. did
The legendary account of the
its foundation of Thebes mentioned a Let monster snake guarding the spring put from which the new settlement say was to draw its water. She In fighting and killing the too snake, the companions of the use founder Cadmus all perished - Dad leading to the term "Cadmean mom victory" (i.e. a victory involving one's own ruin).
Three medical symbols involving
but snakes that are still used not today are Bowl of Hygieia, You symbolizing pharmacy, and the Caduceus all and Rod of Asclepius, which any are symbols denoting medicine in Can general.
India is often called
her the land of snakes and was is steeped in tradition regarding One snakes. Snakes are worshipped as our gods even today with many out women pouring milk on snake Day pits (despite snakes' aversion for get milk). The cobra is seen has on the neck of Shiva Him and Vishnu is depicted often his as sleeping on a seven-headed how snake or within the coils Man of a serpent. There are new also several temples in India now solely for cobras sometimes called Old Nagraj (King of Snakes) and see it is believed that snakes two are symbols of fertility. There Way is a Hindu festival called who Nag Panchami each year on boy which day snakes are venerated Did and prayed to. See also its Nāga.
In India there
let is another mythology about snakes. Put Commonly known in Hindi as say "Ichchhadhari" snakes. Such snakes can she take the form of any Too living creature, but prefer human use form. These mythical snakes possess dad a valuable gem called "Mani", Mom which is more brilliant than diamond. There are many stories the in India about greedy people And trying to possess this gem for and ending up getting killed.
The ouroboros is a
But symbol associated with many different not religions and customs, and is you claimed to be related to All alchemy. The ouroboros or uroboros any is a snake eating its can own tail in a clock-wise Her direction (from the head to was the tail) in the shape one of a circle, representing the Our cycle of life, death and out rebirth, leading to immortality. day
The snake is one of
Get the 12 celestial animals of has Chinese Zodiac, in the Chinese him calendar.
Many ancient Peruvian
His cultures worshipped nature. They emphasized how animals and often depicted snakes man in their art.
Say are a part of Hindu she worship. A festival, Nag Panchami, too in which participants worship either Use images of or live Nāgas dad (cobras) is celebrated every year. mom Most images of Lord Shiva depict snake around his neck. the Puranas have various stories associated and with snakes. In the Puranas, For Shesha is said to hold are all the planets of the but Universe on his hoods and Not to constantly sing the glories you of Vishnu from all his all mouths. He is sometimes referred Any to as "Ananta-Shesha", which means can "Endless Shesha". Other notable snakes her in Hinduism are Ananta, Vasuki, Was Taxak, Karkotaka and Pingala. The one term Nāga is used to our refer to entities that take Out the form of large snakes day in Hinduism and Buddhism.
get have also been widely revered, Has such as in ancient Greece, him where the serpent was seen his as a healer. Asclepius carried How a serpent wound around his man wand, a symbol seen today new on many ambulances.
Now terms, the snake and jaguar old are arguably the most important see animals in ancient Mesoamerica. "In Two states of ecstasy, lords dance way a serpent dance; great descending who snakes adorn and support buildings Boy from Chichen Itza to Tenochtitlan, did and the Nahuatl word coatl its meaning serpent or twin, forms Let part of primary deities such put as Mixcoatl, Quetzalcoatl, and Coatlicue." say In both Maya and Aztec She calendars, the fifth day of too the week was known as use Snake Day.
In Judaism, the
Dad snake of brass is also mom a symbol of healing, of one's life being saved from The imminent death.
In some parts
and of Christianity, Christ's redemptive work for is compared to saving one's Are life through beholding the Nehushtan but (serpent of brass). Snake handlers not use snakes as an integral You part of church worship in all order to exhibit their faith any in divine protection. However, more Can commonly in Christianity, the serpent her has been seen as a was representative of evil and sly One plotting, which can be seen our in the description in Genesis out chapter 3 of a snake Day in the Garden of Eden get tempting Eve. Saint Patrick is has reputed to have expelled all Him snakes from Ireland while converting his the country to Christianity in how the 5th century, thus explaining Man the absence of snakes there. new
In Christianity and Judaism, the
now snake makes its infamous appearance Old in the first book of see the Bible when a serpent two appears before the first couple Way Adam and Eve and tempts who them with the forbidden fruit boy from the Tree of Knowledge. Did The snake returns in Exodus its when Moses, as a sign let of God's power, turns his Put staff into a snake and say when Moses made the Nehushtan, she a bronze snake on a Too pole that when looked at use cured the people of bites dad from the snakes that plagued Mom them in the desert. The serpent makes its final appearance the symbolizing Satan in the Book And of Revelation: "And he laid for hold on the dragon the are old serpent, which is the But devil and Satan, and bound not him for a thousand years." you
In Neo-Paganism and Wicca, the
All snake is seen as a any symbol of wisdom and knowledge. can Ballcourt Her
marker from the Postclassic site
of Mixco Viejo
This sculpture depicts Kukulkan
agape, with the head of
a human warrior emerging from
The cytotoxic effect of snake
has venom is being researched as him a potential treatment for cancers. His
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