Vipera berus: Difference between revisions

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{{subpages}}
{{Taxobox
{{Taxobox
| color = pink
| color = pink
| name = ''Vipera berus''
| name = ''Vipera berus''
| image = Vipera berus (Marek Szczepanek).jpg
| regnum = Animalia
| image_width = 250px
| phylum = Chordata
| regnum = [[Animal]]ia
| subphylum = Vertebrata
| phylum = [[Chordata]]
| classis = Reptilia
| subphylum = [[Vertebrate|Vertebrata]]
| ordo = Squamata
| classis = [[Reptile|Reptilia]]
| subordo = [[Snake (animal)|Serpentes]]
| ordo = [[Squamata]]
| familia = Viperidae
| subordo = [[Snake|Serpentes]]
| familia = [[Viperidae]]
| subfamilia = [[Viperinae]]
| subfamilia = [[Viperinae]]
| genus = ''[[Vipera]]''
| genus = ''[[Vipera]]''
| species = '''''V. berus'''''
| species = '''''V. berus'''''
| binomial = ''Vipera berus''
| binomial = ''Vipera berus''
| binomial_authority = ([[Carolus Linnaeus|Linnaeus]], [[1758]])
| binomial_authority = (Linnaeus, 1758)
| synonyms = * [''Coluber''] ''berus'' - Linnaeus, 1758
| synonyms = * [''Coluber''] ''berus'' - Linnaeus, 1758
* [''Coluber''] ''Chersea'' - Linnaeus, 1758
* [''Coluber''] ''Chersea'' - Linnaeus, 1758
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'''Common names:''' common European adder,<ref name="Mal03">Mallow D, Ludwig D, Nilson G. 2003. True Vipers: Natural History and Toxinology of Old World Vipers. Krieger Publishing Company, Malabar, Florida. 359 pp. ISBN 0-89464-877-2.</ref> common European viper,<ref name="Sti74">Stidworthy J. 1974. Snakes of the World. Grosset & Dunlap Inc. 160 pp. ISBN 0-448-11856-4.</ref> European viper,<ref name="USN91">U.S. Navy. 1991. Poisonous Snakes of the World. US Govt. New York: Dover Publications Inc. 203 pp. ISBN 0-486-26629-X.</ref> [[Vipera berus#Common names|more]].
'''Common names:''' common European adder,<ref name="Mal03">Mallow D, Ludwig D, Nilson G. 2003. True Vipers: Natural History and Toxinology of Old World Vipers. Krieger Publishing Company, Malabar, Florida. 359 pp. ISBN 0-89464-877-2.</ref> common European viper,<ref name="Sti74">Stidworthy J. 1974. Snakes of the World. Grosset & Dunlap Inc. 160 pp. ISBN 0-448-11856-4.</ref> European viper,<ref name="USN91">U.S. Navy. 1991. Poisonous Snakes of the World. US Govt. New York: Dover Publications Inc. 203 pp. ISBN 0-486-26629-X.</ref> [[Vipera berus#Common names|more]].
&nbsp;<br/>
&nbsp;<br/>
'''''Vipera berus''''' is a venomous [[Viperinae|viper]] species that is extremely widespread and can be found throughout most of Western Europe and Great Britain and all the way to Far East Asia.<ref name="McD99"/> Three subspecies are recognized, including the typical form described here.<ref name="ITIS">[http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=634988 ''Vipera berus'' (TSN 634988)] at [http://www.itis.gov/index.html Integrated Taxonomic Information System]. Accessed 25 March 2007.</ref>


==Description==
The body is relatively short and thick-set, with the males are usually shorter and slimmer than the females. Adults grow to 60 cm in length with an average of 55 cm. Maximum size varies per region. The largest -- over 90 cm -- are found in Sweden; specimens of 104 cm have been observed there on two occasions. In France and Great Britain, the maximum size is 80-87 cm.<ref name="Mal03"/> It would seem likely that largest sizes mentioned were indeed attained by female specimens, but this is not mentioned specifically in the literature.


'''''Vipera berus''''' is a [[venomous snake|venomous]] [[Viperinae|viper]] [[species]] that is extremely widespread and can be found throughout most of [[western Europe]] and [[Great Britain]] and all the way to [[Far East Asia]].<ref name="McD99"/> Three subspecies are recognized, including the typical form described here.<ref name="ITIS">{{ITIS|ID=634988|taxon=Vipera berus|year=2006|date=15 August}}</ref>
The head is distinct, the sides of which are almost flat and vertical. The edge of the the snout is usually raised into a low ridge. Seen from above, the [[rostral scale]] is not visible, or only just. Immediately behind the rostral, there are 2 (rarely 1) small scales. Dorsally, there are usually 5 large plates: a squarish [[Frontal scale|frontal]] (longer than wide, sometimes rectangular), 2 [[Parietal scales|parietals]] (sometimes with a tiny scale between the frontal and the parietals), and 2 long and narrow [[supraoculars]]. The latter are large and distinct, each separated from the frontal by 1-4 small scales. The nostril is situated in a shallow depression within a large [[nasal scale]]. The eye is relatively large -- equal in size or slightly larger than the nasal scale -- but often smaller in females. Below the supraoculars there are 6-13 (usually 8-10) small [[circumorbital scales]]. The [[temporal scales]] are smooth (rarely weakly keeled). There are 10-12 [[sublabials]] and 6-10 (usually 8-9) [[supralabials]]. Of the latter, the numbers 3 and 4 are the largest, while 4 and 5 (rarely 3 and 4) are separated from the eye by a single row of small scales (sometimes 2 rows in alpine specimens).<ref name="Mal03"/>
 
==Description==
Relatively thick-bodied, adults grow to 60 cm in length with an average of 55 cm. Maximum size varies per region. The largest -- over 90 cm -- are found in Sweden; specimens of 104 cm have been observed there on two occasions. In France and Great Britain, the maximum size is 80-87 cm.<ref name="Mal03"/>
[[Image:Hugorme.jpg|right|left|thumb|250px|''V. berus'': normal and melanistic color patterns.]]
The head is fairly large and distinct, the sides of which are almost flat and vertical. The edge of the the snout is usually raised into a low ridge. Seen from above, the [[rostral scale]] is not visible, or only just. Immediately behind the rostral, there are 2 (rarely 1) small scales. Dorsally, there are usually 5 large plates: a squarish [[Frontal scale|frontal]] (longer than wide, sometimes rectangular), 2 [[Parietal scales|parietals]] (sometimes with a tiny scale between the frontal and the parietals), and 2 long and narrow [[supraoculars]]. The latter are large and distinct, each separated from the frontal by 1-4 small scales. The nostril is situated in a shallow depression within a large [[nasal scale]]. The eye is relatively large -- equal in size or slightly larger than the nasal scale -- but often smaller in females. Below the supraoculars there are 6-13 (usually 8-10) small [[circumorbital scales]]. The [[temporal scales]] are smooth (rarely weakly keeled). There are 10-12 [[sublabials]] and 6-10 (usually 8-9) [[supralabials]]. Of the latter, the numbers 3 and 4 are the largest, while 4 and 5 (rarely 3 and 4) are separated from the eye by a single row of small scales (sometimes 2 rows in alpine specimens).<ref name="Mal03"/>


Midbody there are 21 [[dorsal scales]] rows (rarely 19, 20, 22 or 23). These are strongly keeled, except for those bodering the [[ventral scales]]. These scales seem loosely attached to the skin and lower rows become increasingly wide; those closest to the ventral scales are twice as wide as the ones along the midline. The ventral scales number 132-150 in males and 132-158 in females. The [[anal plate]] is single. The [[Subcaudal scales|subcaudals]] are paired, numbering 32-46 in males and 23-38 in females.<ref name="Mal03"/>
Midbody there are 21 [[dorsal scales]] rows (rarely 19, 20, 22 or 23). These are strongly keeled, except for those bodering the [[ventral scales]]. These scales seem loosely attached to the skin and lower rows become increasingly wide; those closest to the ventral scales are twice as wide as the ones along the midline. The ventral scales number 132-150 in males and 132-158 in females. The [[anal plate]] is single. The [[Subcaudal scales|subcaudals]] are paired, numbering 32-46 in males and 23-38 in females.<ref name="Mal03"/>


The color pattern varies, ranging from very light-colored specimens with small incomplete dark dorsal crossbars to melanistic individuals that are entirely dark and lack any apparent dorsal pattern. However, most have some kind of zigzig dorsal pattern down the entire length of the body and tail. The head usually has a distinctive dark V or X on the back. A dark streak runs from the eye to the neck and continues as a longitudinal series of spots along the flanks.<ref name="Mal03"/>
{{Image|Whitehorse Hill (2)v3.jpg|right|350px|Adder (viper) on [[Dartmoor]]}}The color pattern varies, ranging from very light-colored specimens with small incomplete dark dorsal crossbars to melanistic individuals that are entirely dark and lack any apparent dorsal pattern. However, most have some kind of zigzig dorsal pattern down the entire length of the body and tail. The head usually has a distinctive dark V or X on the back. A dark streak runs from the eye to the neck and continues as a longitudinal series of spots along the flanks.<ref name="Mal03"/>


==Common names==
==Common names==
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==Geographic range==
==Geographic range==
From [[western Europe]] ([[Great Britain]], [[Scandinavia]], [[France]]) across [[Central Europe|central]] ([[Italy]], [[Albania]], [[Bulgaria]] and northern [[Greece]]) and [[eastern Europe]] to north of the [[Arctic Circle]], and [[Russia]] to the [[Pacific Ocean]], [[Sakhalin Island]], [[North Korea]], northern [[Mongolia]] and northern [[China]]. The [[Type locality (biology)|type locality]] is listed as "Europa." Mertens and Müller (1940) proposed restricting the type locality to "Upsala, Schweden" (Uppsala, Sweden).<ref name="McD99"/>
From Western Europe (Great Britain, Scandinavia, France) across Central Europe (Italy, Albania, Bulgaria and northern Greece) and Eastern Europe to north of the Arctic Circle, and Russia to the Pacific Ocean, Sakhalin Island, North Korea, northern Mongolia and northern China. The type locality is listed as "Europa." Mertens and Müller (1940) proposed restricting the type locality to "Upsala, Schweden" (Uppsala, Sweden).<ref name="McD99"/>


==Conservation status==
==Conservation status==
This species is listed as protected (Appendix III) under the [[Convention on the Conservation of European Wildlife and Natural Habitats|Berne Convention]].<ref name="COE">[http://conventions.coe.int/treaty/FR/Treaties/Html/104-3.htm Convention on the Conservation of European Wildlife and Natural Habitats, Appendix III] at [http://conventions.coe.int/ Council of Europe]. Accessed 9 October 2006.</ref>
This species is listed as protected (Appendix III) under the Berne Convention (Convention on the Conservation of European Wildlife and Natural Habitats).<ref name="COE">[http://conventions.coe.int/treaty/FR/Treaties/Html/104-3.htm Convention on the Conservation of European Wildlife and Natural Habitats, Appendix III] at [http://conventions.coe.int/ Council of Europe]. Accessed 9 October 2006.</ref>


==Habitat==
==Habitat==
[[Image:Viperaberus2.jpg|right|left|thumb|250px|''V. berus'']]Sufficient habitat complexity is a crucial requirement for the presence of this species, in order to support their various behaviors -- basking, foraging and hibernation -- as well as to offer some protection from predators and human harassment.<ref name="Mal03"/> It is found in variety of habitats, including: chalky downs, rocky hillsides, moors, sandy heaths, meadows, rough commons, edges of woods, sunny glades and clearings, bushy slopes and hedgerows, dumps, coastal dunes and stone quarries. If dry ground is locally available, they will not avoid wetlands. Therefore, they may be found on the banks of streams, lakes and ponds.<ref name="Str79">Street D. 1979. The Reptiles of Northern and Central Europe. London: B.T. Batsford Ltd. ISBN 0-7134-1374-3.</ref>
Sufficient habitat complexity is a crucial requirement for the presence of this species, in order to support their various behaviors -- basking, foraging and hibernation -- as well as to offer some protection from predators and human harassment.<ref name="Mal03"/> It is found in variety of habitats, including: chalky downs, rocky hillsides, moors, sandy heaths, meadows, rough commons, edges of woods, sunny glades and clearings, bushy slopes and hedgerows, dumps, coastal dunes and stone quarries. If dry ground is locally available, they will not avoid wetlands. Therefore, they may be found on the banks of streams, lakes and ponds.<ref name="Str79">Street D. 1979. The Reptiles of Northern and Central Europe. London: B.T. Batsford Ltd. ISBN 0-7134-1374-3.</ref>


In much of [[southern Europe]], such as southern [[France]] and northern [[Italy]], it is found in either low lying wetlands or at high altitudes. In the [[Swiss Alps]], it may ascend to about 3000 m. In [[Hungary]] and [[Russia]], it avoids open steppeland; a habitat in which ''[[Vipera ursinii|V. ursinii]]'' is more likely to occur. In Russia, however, it does occur in the forest steppe zone.<ref name="Str79"/>
In much of southern Europe, such as southern France and northern Italy, it is found in either low lying wetlands or at high altitudes. In the Swiss Alps, it may ascend to about 3000 m. In Hungary and Russia, it avoids open steppeland; a habitat in which ''[[Vipera ursinii|V. ursinii]]'' is more likely to occur. In Russia, however, it does occur in the forest steppe zone.<ref name="Str79"/>


==Behavior==
==Behavior==
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Generally speaking, this is not an aggressive species, tending to be rather timid and biting only when cornered or alarmed. Many people are only bitten after stepping on them. They will usually disappear into the undergrowth at a hint of any danger, but will return once all is quiet, often to the same spot. Occasionally, individuals will reveal their presence with a loud and sustained hissing, hoping to warn off potential aggressors. Often, these turn out to be pregnant females. When threatened, the front part of the body is drawn into a S-shape to prepare for a strike.<ref name="Str79"/>
Generally speaking, this is not an aggressive species, tending to be rather timid and biting only when cornered or alarmed. Many people are only bitten after stepping on them. They will usually disappear into the undergrowth at a hint of any danger, but will return once all is quiet, often to the same spot. Occasionally, individuals will reveal their presence with a loud and sustained hissing, hoping to warn off potential aggressors. Often, these turn out to be pregnant females. When threatened, the front part of the body is drawn into a S-shape to prepare for a strike.<ref name="Str79"/>


This is a cold-adapted species that hibernates in the winter. In [[Great Britain]], males and females hibernate for about 150 and 180 days respectively. However, in northern [[Sweden]] hibernation lasts 8-9 months. On mild winter days, they may emerge to bask where the snow has melted and will often travel across snow. Nevertheless, about 15% of adults and 30-40% of juveniles die during hibernation.<ref name="Mal03"/>
This is a cold-adapted species that hibernates in the winter. In Great Britain, males and females hibernate for about 150 and 180 days respectively. However, in northern Sweden hibernation lasts 8-9 months. On mild winter days, they may emerge to bask where the snow has melted and will often travel across snow. Nevertheless, about 15% of adults and 30-40% of juveniles die during hibernation.<ref name="Mal03"/>


==Feeding==
==Feeding==
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==Reproduction==
==Reproduction==
In [[Hungary]], mating takes place in the last week of April, while in the north it happens later in the second week of May. Matings have also been observed in June and even early October, but it is not known if the autumn matings result in any young.<ref name="Mal03"/> Females often breed once every two years,<ref name="Str79"/> or even once every three years if the seasons are short and the climate is severe.<ref name="Mal03"/>
In Hungary, mating takes place in the last week of April, while in the north it happens later in the second week of May. Matings have also been observed in June and even early October, but it is not known if the autumn matings result in any young.<ref name="Mal03"/> Females often breed once every two years,<ref name="Str79"/> or even once every three years if the seasons are short and the climate is severe.<ref name="Mal03"/>
[[Image:Viperaberus1.jpg|right|left|thumb|250px|''V. berus'']]
 
Males find females by following their scent trails, sometimes tracking them for hundreds of meters a day. If a female is found and flees, the male follows. Courtship involves side-by-side parallel "flowing" behavior, tongue flicking along the back and excited lashing of the tail. Pairs stay together for one or two days after mating. Males chase away their rivals and engage in combat. Often, this also starts with the aforementioned flowing behavior before culminating in the dramatic "adder dance."<ref name="Mal03"/> In this act, the males confront each other, raise up the front part of the body vertically, make swaying movements and attempt to push each other to the ground. This is repeated until one of the two becomes exhausted and crawls off to find another mate. Interestingly, Appleby (1971) notes that he has never seen an intruder win one of these contests, as if the frustrated defender is so aroused by courtship that he refuses to loose his chance to mate. There are no records of any biting taking place during these bouts.<ref name="Str79"/>
Males find females by following their scent trails, sometimes tracking them for hundreds of meters a day. If a female is found and flees, the male follows. Courtship involves side-by-side parallel "flowing" behavior, tongue flicking along the back and excited lashing of the tail. Pairs stay together for one or two days after mating. Males chase away their rivals and engage in combat. Often, this also starts with the aforementioned flowing behavior before culminating in the dramatic "adder dance."<ref name="Mal03"/> In this act, the males confront each other, raise up the front part of the body vertically, make swaying movements and attempt to push each other to the ground. This is repeated until one of the two becomes exhausted and crawls off to find another mate. Interestingly, Appleby (1971) notes that he has never seen an intruder win one of these contests, as if the frustrated defender is so aroused by courtship that he refuses to loose his chance to mate. There are no records of any biting taking place during these bouts.<ref name="Str79"/>


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==Venom==
==Venom==
Because of the rapid rate of human expansion throughout the range of this species, bites are relatively common. Domestic animals and livestock are frequent victims. In [[Great Britain]], most instances occur in March-October. In [[Sweden]], there are about 1300 bites a year, with an estimated 12% that require hospitalization.<ref name="Mal03"/>
Because of the rapid rate of human expansion throughout the range of this species, bites are relatively common. Domestic animals and livestock are frequent victims. In Great Britain, most instances occur in March-October. In Sweden, there are about 1,300 bites a year, with an estimated 12% that require hospitalization.<ref name="Mal03"/>
 
Mallow et al. (2003) describe the venom toxicity as being relatively low compared to other viper species. They cite Minton (1974) who reported the LD<font size="-1"><sup>50</sup></font> values for mice to be 0.55 mg/kg IV, 0.80 mg/kg IP and 6.45 mg/kg SC. As a comparison, in one test the minimum lethal dose of for a guinea pig was 40-67 mg, but only 1.7 mg was necessary when ''[[Daboia|D. russelii]]'' venom was used. Brown (1973) gives a higher subcutaneous LD<font size="-1"><sup>50</sup></font> range of 1.0-4.0 mg/kg.<ref name="Bro73">Brown JH. 1973. Toxicoloy and Pharmacology of Venoms from Poisonous Snakes. Springfield, Illinois: Charles C. Thomas. LCCCN 73-229. ISBN 0-398-02808-7.</ref> All agree that the venom yield is low: Minton (1974) mentions 10-18 mg for specimens 48-62 cm in length,<ref name="Mal03"/> while Brown (1973) lists only 6 mg.<ref name="Bro73"/>


The venom has [[hemotoxic]] and [[cytotoxic]] effects, though its potency is relatively low compared to other species of viper. Minton (1974) reported the subcutaneous [[LD50|LD<font size ="-1"><sub>50</sub></font>]] to be 6.45 mg/kg. As a comparison, in one test the minimum lethal dose of for a guinea pig was 40-67 mg, but only 1.7 mg was necessary when ''[[Daboia|D. russelii]]'' venom was used. The venom yield is also low: Minton (1974) mentions 10-18 mg for specimens 48-62 cm in length.<ref name="Mal03"/> Brown (1973) lists a yield of only 6 mg.<ref name="Bro73">Brown JH. 1973. Toxicoloy and Pharmacology of Venoms from Poisonous Snakes. Springfield, Illinois: Charles C. Thomas. LCCCN 73-229. ISBN 0-398-02808-7.</ref>
[[Image:Vipera berus.jpg|right|thumb|250px|''V. berus'']]
Relatively speaking, bites from this species are not highly dangerous.<ref name="Mal03"/> There have been only 14 known fatalities since 1876; the last a 5 year old child in 1975. Even so, professional medical help should always be contacted as soon as possible after any bite. Very occasionally bites can be life threatening, particularly in small children, while adults may experience discomfort and disability long after the bite.<ref name="War05">Warrell DA. 2005. Treatment of bites by adders and exotic venomous snakes. British Medical Journal 331:1244-7. [http://bmj.bmjjournals.com/cgi/reprint/331/7527/1244.pdf PDF] at [http://bmj.bmjjournals.com/ bmj.com]. Accessed 15 September 2006.</ref> The length of recovery varies, but may take up to a year.<ref name="Mal03"/>
Relatively speaking, bites from this species are not highly dangerous.<ref name="Mal03"/> There have been only 14 known fatalities since 1876; the last a 5 year old child in 1975. Even so, professional medical help should always be contacted as soon as possible after any bite. Very occasionally bites can be life threatening, particularly in small children, while adults may experience discomfort and disability long after the bite.<ref name="War05">Warrell DA. 2005. Treatment of bites by adders and exotic venomous snakes. British Medical Journal 331:1244-7. [http://bmj.bmjjournals.com/cgi/reprint/331/7527/1244.pdf PDF] at [http://bmj.bmjjournals.com/ bmj.com]. Accessed 15 September 2006.</ref> The length of recovery varies, but may take up to a year.<ref name="Mal03"/>


Local symptoms include immediate and intense pain, followed after a few minutes (but perhaps by as much as 30 minutes) by swelling and a tingling sensation. Blisters containing blood are not common. The pain may spread within a few hours, along with tenderness and inflammation. Reddish lymphangitic lines and bruising may appear, and the whole limb can become swollen and bruised within 24 hours. Swelling may also spread to the trunk, and with children, throughout the entire body. Necrosis and intracompartmental syndromes are very rare.<ref name="War05"/>
Local symptoms include immediate and intense pain, followed after a few minutes (but perhaps by as much as 30 minutes) by swelling and a tingling sensation. Blisters containing blood are not common. The pain may spread within a few hours, along with tenderness and inflammation. Reddish lymphangitic lines and bruising may appear, and the whole limb can become swollen and bruised within 24 hours. Swelling may also spread to the trunk, and with children, throughout the entire body. Necrosis and intracompartmental syndromes are very rare.<ref name="War05"/>


Systemic symptoms resulting from [[anaphylaxis]] can be dramatic. These may appear within 5 minutes post bite, or can be delayed for many hours. Such symptoms include nausea, retching and vomiting, abdominal colic and diarrhoea, incontinence of urine and faeces, sweating, fever, [[vasoconstriction]], [[tachycardia]], lightheadedness, loss of consciousness, [[shock]], [[angioedema]] of the face, lips, gums, tongue, throat and [[epiglotis]], [[urticaria]] and bronchospam. If left untreated, these symptoms may persist or fluctuate for up to 48 hours.<ref name="War05"/> In severe cases, cardiovascular failure may occur.<ref name="Mal03"/>
Systemic symptoms resulting from anaphylaxis can be dramatic. These may appear within 5 minutes post bite, or can be delayed for many hours. Such symptoms include nausea, retching and vomiting, abdominal colic and diarrhoea, incontinence of urine and faeces, sweating, fever, vasoconstriction, tachycardia, lightheadedness, loss of consciousness, shock, angioedema of the face, lips, gums, tongue, throat and epiglotis, urticaria and bronchospam. If left untreated, these symptoms may persist or fluctuate for up to 48 hours.<ref name="War05"/> In severe cases, cardiovascular failure may occur.<ref name="Mal03"/>


At least eight different antivenins are available against bites from this species.<ref name="MAVIN">[http://www.toxinfo.org/antivenoms/indication/VIPERA_BERUS.html ''Vipera berus'' antivenoms] at [http://www.toxinfo.org/antivenoms/ Munich Antivenom Index]. Accessed 15 September 2006.</ref>
At least eight different antivenins are available against bites from this species.<ref name="MAVIN">[http://www.toxinfo.org/antivenoms/indication/VIPERA_BERUS.html ''Vipera berus'' antivenoms] at [http://www.toxinfo.org/antivenoms/ Munich Antivenom Index]. Accessed 15 September 2006.</ref>
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|-
|-
|''V. b. berus''
|''V. b. berus''
|([[Carolus Linnaeus|Linnaeus]], [[1758]])
|(Linnaeus, 1758)
|style="width:60%"|[[Norway]], [[Sweden]], [[Finland]], [[Estonia]], [[France]], [[Denmark]], [[Germany]], [[Austria]], [[Switzerland]], Northern [[Italy]], [[Belgium]], [[Netherlands]], [[Great Britain]], [[Poland]], [[Czech Republic]], [[Slovakia]], [[Hungary]], [[Romania]], [[Russia]], [[Mongolia]], north-west [[China]] (north [[Xinjiang]])  
|style="width:60%"|Norway, Sweden, Finland, Estonia, France, Denmark, Germany, Austria, Switzerland, Northern Italy, Belgium, Netherlands, Great Britain, Poland, Czech Republic, Slovakia, Hungary, Romania, Russia, Mongolia, north-west China (northern Xinjiang).
|-
|-
|''[[Vipera berus bosniensis|V. b. bosniensis]]''
|''[[Vipera berus bosniensis|V. b. bosniensis]]''
|[[Johann Friedrich Böttger|Boettger]], [[1889]]
|Boettger, 1889
|[[Balkan Peninsula]]
|Balkan Peninsula
|-
|-
|''[[Vipera berus sachalinensis|V. b. sachalinensis]]''
|''[[Vipera berus sachalinensis|V. b. sachalinensis]]''
|Zarevskij, [[1917]]
|Zarevskij, 1917
|Russian Far East (Amur Oblast, Primorskye Kray, Khabarovsk Kray, Sakhalin Island), [[North Korea]], north-east China ([[Jilin]])
|Russian Far East (Amur Oblast, Primorskye Kray, Khabarovsk Kray, Sakhalin Island), North Korea, north-east China (Jilin).
|-
|-
|}
|}
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* [[List of viperine species and subspecies]].
* [[List of viperine species and subspecies]].
* [[:Category:True vipers - Common names|True vipers - Common names]].
* [[:Category:True vipers - Common names|True vipers - Common names]].
* [[Snakebite]].
* [[:Category:True vipers - Synonymy|True vipers - Synonymy]].
* [[Snake (animal)bite]].


==Cited references==
==Cited references==
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* Joger U, Lenk P, Baran I, Böme W, Ziegler T, Heidrich P, Wink M. 1997. The phylogenetic position of ''Vipera barani'' and of ''Vipera nikolskii'' within the ''Vipera berus'' complex.
* Joger U, Lenk P, Baran I, Böme W, Ziegler T, Heidrich P, Wink M. 1997. The phylogenetic position of ''Vipera barani'' and of ''Vipera nikolskii'' within the ''Vipera berus'' complex.
* Minton SA Jr. 1974. Venom Diseases. Springfield (IL): CC Thomas Publ. 386 pp.
* Minton SA Jr. 1974. Venom Diseases. Springfield (IL): CC Thomas Publ. 386 pp.
* Wüster W, Allum CSE, Bjargardottir IB, Bailey KL, Dawson KJ, Guenioui J, Lewis J, McGurk J, Moore AG, Niskanen M, Pollard CP. 2004. Do aposematism and Batesian mimicry require bright colours? A test, using European viper markings. Proceedings of the Royal Society of London. B 271 pp 2495-2499. [http://biology.bangor.ac.uk/~bss166/Publications/2004_Viper_Aposematism_online.pdf PDF] at [http://biology.bangor.ac.uk/~bss166/ Wolfgang Wüster, School of Biological Sciences, University of Wales, Bangor]. Accessed on [[15 August]] [[2006]].
* Wüster W, Allum CSE, Bjargardottir IB, Bailey KL, Dawson KJ, Guenioui J, Lewis J, McGurk J, Moore AG, Niskanen M, Pollard CP. 2004. Do aposematism and Batesian mimicry require bright colours? A test, using European viper markings. Proceedings of the Royal Society of London. B 271 pp 2495-2499. [http://biology.bangor.ac.uk/~bss166/Publications/2004_Viper_Aposematism_online.pdf PDF] at [http://biology.bangor.ac.uk/~bss166/ Wolfgang Wüster, School of Biological Sciences, University of Wales, Bangor]. Accessed on 15 August 2006.
</div>
</div>


==External links==
[[Category:Suggestion Bot Tag]]
{{Commons|Vipera berus}}
* [http://www.herp.it/SpeciesPages/ViperBerus.htm ''Vipera berus''] at [http://www.herp.it/ Amphibians and Reptiles of Europe]. Accessed on [[16 August]] [[2006]].
* [http://www.arkive.org/species/ARK/reptiles/Vipera_berus/ Adder (''Vipera berus'')] at [http://www.arkive.org/ ARKive]. Accessed [[9 October]] [[2006]].
* [http://www.herpetofauna.co.uk/adder.htm Adder or Viper - ''Vipera berus''] at [http://www.herpetofauna.co.uk/ Reptiles and Amphibians of the UK]. Accessed [[9 October]] [[2006]].
* [http://www.club100.net/species/V_berus/V_berus.html ''Vipera berus''] at [http://www.club100.net/ Club100]. Accessed [[9 October]] [[2006]].
* [http://www.first-nature.com/reptiles/vipera_berus.htm ''Viper berus'' - Adder] at [http://www.first-nature.com/ First Nature]. Accessed [[9 October]] [[2006]].
* [http://www.wartsoc.co.uk/vb.html Adder (''Vipera berus'')] at [http://www.wartsoc.co.uk/ Warwickshire Amphibian and Reptile Team]. Accessed [[9 October]] [[2006]].
* [http://www.swedishorphan.com/templates/SWORP/Normal.asp?id=3679 Vipera Berus bite] at [http://www.swedishorphan.com/ Swedish Orphan International]. Accessed [[9 October]] [[2006]].
* [http://www.reptilia-amphibia.net/index.html?en/snake/berus.html~mainFrame Adder, ''Vipera berus''] at [http://www.reptilia-amphibia.net/ Reptiles & Amphibians of France]. Accessed [[30 October]] [[2006]].
 
[[Category:True vipers]]
[[Category:CZ Live]]

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Vipera berus
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Class: Reptilia
Order: Squamata
Suborder: Serpentes
Family: Viperidae
Subfamily: Viperinae
Genus: Vipera
Species: V. berus
Binomial name
Vipera berus
(Linnaeus, 1758)
Synonyms
  • [Coluber] berus - Linnaeus, 1758
  • [Coluber] Chersea - Linnaeus, 1758
  • Coluber prester - Linnaeus, 1761
  • Coluber vipera Anglorum - Laurenti, 1768
  • Coluber Melanis - Pallas, 1771
  • Coluber Scytha - Pallas, 1773
  • C[oluber]. Scytha - Bonnaterre, 1790
  • Vipera melanis - Sonnini & Latreille, 1801
  • Vipera berus - Daudin, 1803
  • Vipera chersea - Daudin, 1803
  • Vipera prester - Daudin, 1803
  • [Coluber] Caeruleus - Sheppard, 1804
  • Vipera communis - Leach, 1817
  • Coluber chersea var. marasso - Pollini, 1818
  • [Pelias] berus - Merrem, 1820
  • [Vipera] marasso - Sette, 1821
  • Vipera limnaea - Bendiscioli, 1826
  • Vipera trilamina - Millet, 1828
  • [Pelias] Chersea - Wagler, 1830
  • Vipera torva - Lenz, 1832
  • Pelias dorsalis - Gray, 1842
  • V[ipera]. Prester var. gagatina - Freyer, 1842
  • Echidnoides trilamina - Mauduyt, 1844
  • Vipera Pelias - Soubeiran, 1855
  • Pelias berus var. Prester - Günther, 1858
  • Pelias berus var. Chersea - Günther, 1858
  • V[ipera]. (Pelias) berus var. prester - Jan, 1863
  • V[ipera]. (Pelias) berus var. lymnaea - Jan, 1863
  • Pelias Chersea - Erber, 1863
  • Pelias berus - Erber, 1863
  • P[elias berus]. Var. dorsalis - Cope, 1860
  • P[elias berus]. Var. niger - Cope, 1860
  • Vipera berus var. prester - Jan & Sordelli, 1874
  • Vipera berus [berus] - Boettger, 1889
  • [Vipera berus] var. montana - Méhely, 1893
  • Vipera berus - Boulenger, 1896
  • Pelias berus lugubris - Kashehenko, 1902
  • Vipera berus pelias - Chabanaud, 1923
  • [Vipera (Pelias) berus] forma brunneomarcata - Reuss, 1923
  • [Vipera (Pelias) berus] forma luteoalba - Reuss, 1923
  • [Vipera (Pelias) berus] forma ochracea asymmetrica - Reuss, 1923
  • [Vipera (Pelias) berus] rudolphi-marchica - Reuss, 1924
  • [Vipera (Pelias) berus] forma bilineata - Reuss, 1924
  • Vipera (Pelias) berus forma chersea-splendens - Reuss, 1925
  • Vipera (Pelias) berus forma ochracea-splendens - Reuss, 1925
  • Vipera (Pelias) berus forma rutila - Reuss, 1925
  • Vipera (Pelias) berus forma punctata - Reuss, 1925
  • Coluber sachalinensis continentalis - Nikolski, 1927
  • P[elias]. sudetica - Reuss, 1927 (nomen nudum)
  • V[ipera]. berus marchici - Reuss, 1927
  • Vipera berus rudolphi - Reuss, 1927 (nomen nudum)
  • Vipera berus berus - Mertens & Müller, 1928
  • [Pelias] elberfeldi - Reuss, 1929
  • Pelias rudolphi - Reuss, 1930
  • Pelias schöttleri - Reuss, 1930
  • P[elias]. tyrolensis - Reuss, 1930
  • Pelias schreiberi - Reuss, 1930
  • Pelias flavescens - Reuss, 1930 (nomen nudum)
  • Pelias subalpina - Reuss, 1930 (nomen nudum)
  • Pelias neglecta - Reuss, 1932
  • Vipera berus sphagnosa - Krassawzef, 1932
  • Pelias occidentalis - Reuss, 1933
  • Pelias occidentalis oldesloensis - Reuss, 1933 (nomen nudum)
  • Pelias occidentalis orbensis - Reuss, 1933 (nomen nudum)
  • Pelias sudetica forma steinii - Reuss, 1935 (nomen nudum)
  • Vipera marchici - Reuss, 1935
  • Pelias sudetica steinii forma emarcata - Reuss, 1937 (nomen illegitimum)
  • Vipera (Vipera) berus berus - Obst, 1983
  • Vipera berus forma brunneomarcata - Golay et al., 1993
  • Vipera berus forma ochracea-asymmetrica - Golay et al., 1993
  • Vipera berus forma luteoalba - Golay et al., 1993
  • Pelias schoettleri - Golay et al., 1993
  • Coluber coeruleus - Golay et al., 1993
  • Vipera berus - Golay et al., 1993[1]

Common names: common European adder,[2] common European viper,[3] European viper,[4] more.  
 
Vipera berus is a venomous viper species that is extremely widespread and can be found throughout most of Western Europe and Great Britain and all the way to Far East Asia.[1] Three subspecies are recognized, including the typical form described here.[5]

Description

The body is relatively short and thick-set, with the males are usually shorter and slimmer than the females. Adults grow to 60 cm in length with an average of 55 cm. Maximum size varies per region. The largest -- over 90 cm -- are found in Sweden; specimens of 104 cm have been observed there on two occasions. In France and Great Britain, the maximum size is 80-87 cm.[2] It would seem likely that largest sizes mentioned were indeed attained by female specimens, but this is not mentioned specifically in the literature.

The head is distinct, the sides of which are almost flat and vertical. The edge of the the snout is usually raised into a low ridge. Seen from above, the rostral scale is not visible, or only just. Immediately behind the rostral, there are 2 (rarely 1) small scales. Dorsally, there are usually 5 large plates: a squarish frontal (longer than wide, sometimes rectangular), 2 parietals (sometimes with a tiny scale between the frontal and the parietals), and 2 long and narrow supraoculars. The latter are large and distinct, each separated from the frontal by 1-4 small scales. The nostril is situated in a shallow depression within a large nasal scale. The eye is relatively large -- equal in size or slightly larger than the nasal scale -- but often smaller in females. Below the supraoculars there are 6-13 (usually 8-10) small circumorbital scales. The temporal scales are smooth (rarely weakly keeled). There are 10-12 sublabials and 6-10 (usually 8-9) supralabials. Of the latter, the numbers 3 and 4 are the largest, while 4 and 5 (rarely 3 and 4) are separated from the eye by a single row of small scales (sometimes 2 rows in alpine specimens).[2]

Midbody there are 21 dorsal scales rows (rarely 19, 20, 22 or 23). These are strongly keeled, except for those bodering the ventral scales. These scales seem loosely attached to the skin and lower rows become increasingly wide; those closest to the ventral scales are twice as wide as the ones along the midline. The ventral scales number 132-150 in males and 132-158 in females. The anal plate is single. The subcaudals are paired, numbering 32-46 in males and 23-38 in females.[2]

(CC) Photo: Martin Wyatt
Adder (viper) on Dartmoor

The color pattern varies, ranging from very light-colored specimens with small incomplete dark dorsal crossbars to melanistic individuals that are entirely dark and lack any apparent dorsal pattern. However, most have some kind of zigzig dorsal pattern down the entire length of the body and tail. The head usually has a distinctive dark V or X on the back. A dark streak runs from the eye to the neck and continues as a longitudinal series of spots along the flanks.[2]

Common names

Common European adder,[2] common European viper,[3] European viper,[4] northern viper,[6] adder, crossed viper.[7]

Geographic range

From Western Europe (Great Britain, Scandinavia, France) across Central Europe (Italy, Albania, Bulgaria and northern Greece) and Eastern Europe to north of the Arctic Circle, and Russia to the Pacific Ocean, Sakhalin Island, North Korea, northern Mongolia and northern China. The type locality is listed as "Europa." Mertens and Müller (1940) proposed restricting the type locality to "Upsala, Schweden" (Uppsala, Sweden).[1]

Conservation status

This species is listed as protected (Appendix III) under the Berne Convention (Convention on the Conservation of European Wildlife and Natural Habitats).[8]

Habitat

Sufficient habitat complexity is a crucial requirement for the presence of this species, in order to support their various behaviors -- basking, foraging and hibernation -- as well as to offer some protection from predators and human harassment.[2] It is found in variety of habitats, including: chalky downs, rocky hillsides, moors, sandy heaths, meadows, rough commons, edges of woods, sunny glades and clearings, bushy slopes and hedgerows, dumps, coastal dunes and stone quarries. If dry ground is locally available, they will not avoid wetlands. Therefore, they may be found on the banks of streams, lakes and ponds.[9]

In much of southern Europe, such as southern France and northern Italy, it is found in either low lying wetlands or at high altitudes. In the Swiss Alps, it may ascend to about 3000 m. In Hungary and Russia, it avoids open steppeland; a habitat in which V. ursinii is more likely to occur. In Russia, however, it does occur in the forest steppe zone.[9]

Behavior

This is mainly a diurnal species, especially in the north of its range. Further south it is said to be active in the evening, and it may even be active at night during the summer months. It is predominantly a terrestrial species, although it has been known climb up banks and into low bushes in order to bask or search for prey.[9]

Generally speaking, this is not an aggressive species, tending to be rather timid and biting only when cornered or alarmed. Many people are only bitten after stepping on them. They will usually disappear into the undergrowth at a hint of any danger, but will return once all is quiet, often to the same spot. Occasionally, individuals will reveal their presence with a loud and sustained hissing, hoping to warn off potential aggressors. Often, these turn out to be pregnant females. When threatened, the front part of the body is drawn into a S-shape to prepare for a strike.[9]

This is a cold-adapted species that hibernates in the winter. In Great Britain, males and females hibernate for about 150 and 180 days respectively. However, in northern Sweden hibernation lasts 8-9 months. On mild winter days, they may emerge to bask where the snow has melted and will often travel across snow. Nevertheless, about 15% of adults and 30-40% of juveniles die during hibernation.[2]

Feeding

Diet consists mainly of small mammals, such as mice, voles and shrews, as well as lizards. Sometimes, slow worms are taken, and even weasels and moles. They feed on amphibians, such as frogs newts and salamanders. Birds are also reported to be on the menu, especially nestlings and even eggs, for which they they will climb into shrubbery and bushes. Generally, diet varies depending on locality.[9]

Juveniles will eat nestling mammals, small lizards and frogs, as well as insects, worms and spiders. Once they reach about 30 cm in length, their diet begins to resemble that of the adults.[2]

Reproduction

In Hungary, mating takes place in the last week of April, while in the north it happens later in the second week of May. Matings have also been observed in June and even early October, but it is not known if the autumn matings result in any young.[2] Females often breed once every two years,[9] or even once every three years if the seasons are short and the climate is severe.[2]

Males find females by following their scent trails, sometimes tracking them for hundreds of meters a day. If a female is found and flees, the male follows. Courtship involves side-by-side parallel "flowing" behavior, tongue flicking along the back and excited lashing of the tail. Pairs stay together for one or two days after mating. Males chase away their rivals and engage in combat. Often, this also starts with the aforementioned flowing behavior before culminating in the dramatic "adder dance."[2] In this act, the males confront each other, raise up the front part of the body vertically, make swaying movements and attempt to push each other to the ground. This is repeated until one of the two becomes exhausted and crawls off to find another mate. Interestingly, Appleby (1971) notes that he has never seen an intruder win one of these contests, as if the frustrated defender is so aroused by courtship that he refuses to loose his chance to mate. There are no records of any biting taking place during these bouts.[9]

Females usually give birth in August-September, but sometimes as early as July, or as late as early October. Litters range in size from 3 to 20. The young are usually born encased in a transparent sac from which they must free themselves. Sometimes, they succeed in freeing themselves from this membrane while still inside the female. The neonates, measuring 14 to 23 cm (average of 17 cm), are born with a fully functional venom apparatus and a reserve supply of yolk within their bodies. They shed their skins for the first time within a day or two. Females do not appear to take much interest in their offspring, but the young have been observed to remain near their mothers for several days after birth.[9]

Venom

Because of the rapid rate of human expansion throughout the range of this species, bites are relatively common. Domestic animals and livestock are frequent victims. In Great Britain, most instances occur in March-October. In Sweden, there are about 1,300 bites a year, with an estimated 12% that require hospitalization.[2]

Mallow et al. (2003) describe the venom toxicity as being relatively low compared to other viper species. They cite Minton (1974) who reported the LD50 values for mice to be 0.55 mg/kg IV, 0.80 mg/kg IP and 6.45 mg/kg SC. As a comparison, in one test the minimum lethal dose of for a guinea pig was 40-67 mg, but only 1.7 mg was necessary when D. russelii venom was used. Brown (1973) gives a higher subcutaneous LD50 range of 1.0-4.0 mg/kg.[10] All agree that the venom yield is low: Minton (1974) mentions 10-18 mg for specimens 48-62 cm in length,[2] while Brown (1973) lists only 6 mg.[10]

Relatively speaking, bites from this species are not highly dangerous.[2] There have been only 14 known fatalities since 1876; the last a 5 year old child in 1975. Even so, professional medical help should always be contacted as soon as possible after any bite. Very occasionally bites can be life threatening, particularly in small children, while adults may experience discomfort and disability long after the bite.[11] The length of recovery varies, but may take up to a year.[2]

Local symptoms include immediate and intense pain, followed after a few minutes (but perhaps by as much as 30 minutes) by swelling and a tingling sensation. Blisters containing blood are not common. The pain may spread within a few hours, along with tenderness and inflammation. Reddish lymphangitic lines and bruising may appear, and the whole limb can become swollen and bruised within 24 hours. Swelling may also spread to the trunk, and with children, throughout the entire body. Necrosis and intracompartmental syndromes are very rare.[11]

Systemic symptoms resulting from anaphylaxis can be dramatic. These may appear within 5 minutes post bite, or can be delayed for many hours. Such symptoms include nausea, retching and vomiting, abdominal colic and diarrhoea, incontinence of urine and faeces, sweating, fever, vasoconstriction, tachycardia, lightheadedness, loss of consciousness, shock, angioedema of the face, lips, gums, tongue, throat and epiglotis, urticaria and bronchospam. If left untreated, these symptoms may persist or fluctuate for up to 48 hours.[11] In severe cases, cardiovascular failure may occur.[2]

At least eight different antivenins are available against bites from this species.[12]

Subspecies

Subspecies Authority Geographic range
V. b. berus (Linnaeus, 1758) Norway, Sweden, Finland, Estonia, France, Denmark, Germany, Austria, Switzerland, Northern Italy, Belgium, Netherlands, Great Britain, Poland, Czech Republic, Slovakia, Hungary, Romania, Russia, Mongolia, north-west China (northern Xinjiang).
V. b. bosniensis Boettger, 1889 Balkan Peninsula
V. b. sachalinensis Zarevskij, 1917 Russian Far East (Amur Oblast, Primorskye Kray, Khabarovsk Kray, Sakhalin Island), North Korea, north-east China (Jilin).

Taxonomy

The subspecies V. b. bosniensis and V. b. sachalinensis have been regarded as full species in some recent publications.[2]

See also

Cited references

  1. ↑ 1.0 1.1 1.2 McDiarmid RW, Campbell JA, Touré T. 1999. Snake Species of the World: A Taxonomic and Geographic Reference, vol. 1. Herpetologists' League. 511 pp. ISBN 1-893777-00-6 (series). ISBN 1-893777-01-4 (volume).
  2. ↑ 2.00 2.01 2.02 2.03 2.04 2.05 2.06 2.07 2.08 2.09 2.10 2.11 2.12 2.13 2.14 2.15 2.16 2.17 Mallow D, Ludwig D, Nilson G. 2003. True Vipers: Natural History and Toxinology of Old World Vipers. Krieger Publishing Company, Malabar, Florida. 359 pp. ISBN 0-89464-877-2.
  3. ↑ 3.0 3.1 Stidworthy J. 1974. Snakes of the World. Grosset & Dunlap Inc. 160 pp. ISBN 0-448-11856-4.
  4. ↑ 4.0 4.1 U.S. Navy. 1991. Poisonous Snakes of the World. US Govt. New York: Dover Publications Inc. 203 pp. ISBN 0-486-26629-X.
  5. ↑ Vipera berus (TSN 634988) at Integrated Taxonomic Information System. Accessed 25 March 2007.
  6. ↑ Species Vipera berus at the Species2000 Database
  7. ↑ Mehrtens JM. 1987. Living Snakes of the World in Color. New York: Sterling Publishers. 480 pp. ISBN 0-8069-6460-X.
  8. ↑ Convention on the Conservation of European Wildlife and Natural Habitats, Appendix III at Council of Europe. Accessed 9 October 2006.
  9. ↑ 9.0 9.1 9.2 9.3 9.4 9.5 9.6 9.7 Street D. 1979. The Reptiles of Northern and Central Europe. London: B.T. Batsford Ltd. ISBN 0-7134-1374-3.
  10. ↑ 10.0 10.1 Brown JH. 1973. Toxicoloy and Pharmacology of Venoms from Poisonous Snakes. Springfield, Illinois: Charles C. Thomas. LCCCN 73-229. ISBN 0-398-02808-7.
  11. ↑ 11.0 11.1 11.2 Warrell DA. 2005. Treatment of bites by adders and exotic venomous snakes. British Medical Journal 331:1244-7. PDF at bmj.com. Accessed 15 September 2006.
  12. ↑ Vipera berus antivenoms at Munich Antivenom Index. Accessed 15 September 2006.

Other references

  • Ananjeva NB, Borkin LJ, Darevsky IS, Orlov NL. 1998. Amphibiand and Reptiles. Encyclopedia of Nature of Russia. ABF Moscow (in Russian). 574 pp.
  • Appleby LG. 1971. British Snakes. London: J. Baker. 201 pp. ISBN 0-212-98393-8.
  • Joger U, Lenk P, Baran I, Böme W, Ziegler T, Heidrich P, Wink M. 1997. The phylogenetic position of Vipera barani and of Vipera nikolskii within the Vipera berus complex.
  • Minton SA Jr. 1974. Venom Diseases. Springfield (IL): CC Thomas Publ. 386 pp.
  • Wüster W, Allum CSE, Bjargardottir IB, Bailey KL, Dawson KJ, Guenioui J, Lewis J, McGurk J, Moore AG, Niskanen M, Pollard CP. 2004. Do aposematism and Batesian mimicry require bright colours? A test, using European viper markings. Proceedings of the Royal Society of London. B 271 pp 2495-2499. PDF at Wolfgang Wüster, School of Biological Sciences, University of Wales, Bangor. Accessed on 15 August 2006.
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