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==Geographical range, habitat, and status==
==Geographical range, habitat, and status==
Although a large, diurnal, and "notorious" snake, the distribution of the black mamba is the subject of much confusion in research literature, indicating the poor status of African [[herpetology|herpetological]] zoogeography.<ref name='JSTOR'>{{cite journal |authors= Håkansson, Thomas; Madsen, Thomas |title=On the Distribution of the Black Mamba (''Dendroaspis polylepis'') in West Africa |volume=17 |issue=2 |pages=186-187 |month=June |year=1983 |journal=Journal of Herpetology}}</ref> However, the distribution of the black mamba in [[East Africa|eastern Africa]] and [[southern Africa]] is well documented. Pitman (1974) gives the following range for the species' total distribution in Africa: northeast [[Democratic Republic of the Congo]], southwestern [[Sudan]] to [[Ethiopia]], [[Eritrea]], [[Somalia]], [[Kenya]], eastern [[Uganda]], [[Tanzania]], southwards to [[Mozambique]], [[Swaziland]], [[Malawi]], [[Zambia]], [[Zimbabwe]] and [[Botswana]] to [[KwaZulu-Natal]] in South Africa, and [[Namibia]]; then northeasterly through [[Angola]] to the southeastern part of the Democratic Republic of Congo.<ref name='JSTOR'/><ref name=SUBM>[http://www.snakes-uncovered.com/Black_Mamba.html Snakes Uncovered (''D. polylepis'' Information)]</ref> According to [[CITES]], the species is also found in [[Lesotho]], [[Rwanda]], and [[Djibouti]].<ref>[http://www.cites.org/eng/resources/species.html CITES species finder - Black Mamba]</ref> The black mamba is not commonly found above altitudes of {{convert|1000|m|ft}}, although the distribution of black mamba does reach {{convert|1800|m|ft}} in Kenya and {{convert|1650|m|ft}} in Zambia (Spawls, 1978).<ref name='JSTOR'/> The black mamba was also recorded in 1954 in West Africa in the [[Dakar]] region of [[Senegal]].<ref name='JSTOR'/> However, this observation, and a subsequent observation that identified a second specimen in the region in 1956, have not been confirmed and thus the species' distribution in [[West Africa]] is inconclusive.<ref name='JSTOR'/> The black mamba's western distribution contains gaps within the [[Central African Republic]], [[Chad]], [[Nigeria]] and [[Mali]]. These gaps may lead physicians to misidentify the black mamba and administer an ineffective antivenom.<ref name='JSTOR'/>
Although a large, diurnal, and "notorious" snake, the distribution of the black mamba (''D. polylepis polylepis'') is the subject of much confusion in research literature, indicating the poor status of African [[herpetology|herpetological]] zoogeography.<ref name='JSTOR'>{{cite journal |authors= Håkansson, Thomas; Madsen, Thomas |title=On the Distribution of the Black Mamba (''Dendroaspis polylepis'') in West Africa |volume=17 |issue=2 |pages=186-187 |month=June |year=1983 |journal=Journal of Herpetology}}</ref> However, the distribution of the black mamba in [[East Africa|eastern Africa]] and [[southern Africa]] is well documented. Pitman (1974) gives the following range for the species' total distribution in Africa: northeast [[Democratic Republic of the Congo]], southwestern [[Sudan]] to [[Ethiopia]], [[Eritrea]], [[Somalia]], [[Kenya]], eastern [[Uganda]], [[Tanzania]], southwards to [[Mozambique]], [[Swaziland]], [[Malawi]], [[Zambia]], [[Zimbabwe]] and [[Botswana]] to [[KwaZulu-Natal]] in South Africa, and [[Namibia]]; then northeasterly through [[Angola]] to the southeastern part of the Democratic Republic of Congo.<ref name='JSTOR'/><ref name=SUBM>[http://www.snakes-uncovered.com/Black_Mamba.html Snakes Uncovered (''D. polylepis'' Information)]</ref> According to [[CITES]], the species is also found in [[Lesotho]], [[Rwanda]], and [[Djibouti]].<ref>[http://www.cites.org/eng/resources/species.html CITES species finder - Black Mamba]</ref> The black mamba is not commonly found above altitudes of {{convert|1000|m|ft}}, although the distribution of black mamba does reach {{convert|1800|m|ft}} in Kenya and {{convert|1650|m|ft}} in Zambia (Spawls, 1978).<ref name='JSTOR'/> The black mamba was also recorded in 1954 in West Africa in the [[Dakar]] region of [[Senegal]].<ref name='JSTOR'/> However, this observation, and a subsequent observation that identified a second specimen in the region in 1956, have not been confirmed and thus the species' distribution in [[West Africa]] is inconclusive.<ref name='JSTOR'/> The black mamba's western distribution contains gaps within the [[Central African Republic]], [[Chad]], [[Nigeria]] and [[Mali]]. These gaps may lead physicians to misidentify the black mamba and administer an ineffective antivenom.<ref name='JSTOR'/> Antinorii's black mamba occurs only in eastern Africa and is found in Somalia, Ethiopia, Eritrea, northern Kenya, and northeastern Uganda.<ref name='Database'/>


===Habitat===
===Habitat===
The black mamba has adapted to a variety of climates ranging from [[savanna]], [[woodland]]s, farmlands, rocky slopes, dense forests and even humid [[swamps]].<ref name='JSTOR'/> The [[grassland]] and savanna woodland/shrubs that extend all the way from southern and eastern Africa to central and western Africa, eastern and southern Africa are the black mamba's typical habitat.<ref name='JSTOR'/> The black mamba prefers more arid environments such as semi-arid dry bush country, light woodland, and rocky outcrops (Pitman, 1974).<ref name='JSTOR'/> This species likes areas with a lot of hills as well as riverine forests. Black mamba's also often make use of abandoned [[Termite mound#Mounds|termite mounds]] and hollow trees for shelter (Pitman, 1974). The abandoned termite mounds are especially used when the snake is looking for somewhere to cool off as the mounds are sort of a "natural air-conditioning" system. The structure of these mounds is very complex and elaborate. They have a network of holes, ducts, and chimneys that allow air to circulate freely, drawing heat away from the nest during the day - though without taking too much valuable moisture - while preventing the nest cooling too much at night.<ref name=SUBM/> However, as a territorial species the black mamba and so will always return to their territory.
Both subspecies of the black mamba have adapted to a variety of climates ranging from [[savanna]], [[woodland]]s, farmlands, rocky slopes, dense forests and even humid [[swamps]].<ref name='JSTOR'/> The [[grassland]] and savanna woodland/shrubs that extend all the way from southern and eastern Africa to central and western Africa, eastern and southern Africa are the black mamba's typical habitat.<ref name='JSTOR'/> The black mamba prefers more arid environments such as semi-arid dry bush country, light woodland, and rocky outcrops (Pitman, 1974).<ref name='JSTOR'/> This species likes areas with a lot of hills as well as riverine forests. Black mamba's also often make use of abandoned [[Termite mound#Mounds|termite mounds]] and hollow trees for shelter (Pitman, 1974). The abandoned termite mounds are especially used when the snake is looking for somewhere to cool off as the mounds are sort of a "natural air-conditioning" system. The structure of these mounds is very complex and elaborate. They have a network of holes, ducts, and chimneys that allow air to circulate freely, drawing heat away from the nest during the day - though without taking too much valuable moisture - while preventing the nest cooling too much at night.<ref name=SUBM/> However, as a territorial species the black mamba and so will always return to their territory.


===Environmental encroachment===
===Environmental encroachment===

Revision as of 18:29, 3 November 2011

For other uses, see Black mamba (disambiguation).

Black mamba
Scientific classification
Kingdom:
Animalia
Phylum:
Chordata
Subphylum:
Vertebrata
Class:
Reptilia
Order:
Squamata
Suborder:
Serpentes
Family:
Elapidae
Genus:
Dendroaspis
Species:
D. polylepis
Binomial name
Dendroaspis polylepis
Range of the Black Mamba

The black mamba (Dendroaspis polylepis), or black-mouthed mamba,[3] is the longest venomous snake in Africa, averaging around 2.5 meters (8.2 ft) in length, and sometimes growing up to 4.3 meters (14 ft). Its name is derived from the black colouration inside the mouth rather than the actual colour of its scales which varies from dull yellowish-green to a gun-metal grey. It is the fastest snake in the world, capable of moving at 4.32 to 5.4 metres per second (16–20 km/h, 10–12 mph).[1] It's also a very "notorious" snake that's feared throughout the world and it generally has a very bad reputation for being very aggressive, highly venomous, and is often cited as the world's deadliest species by many, both laymen and experts (B. Johnson, July 13, 2000; Hunter, 1998). One expert even calls this species "death incarnate".[4] There are many myths, legends, and stories about this species.[5]

Taxonomy

The Black mamba was first described by Albert Günther, a German-born British zoologist, ichthyologist, and herpetologist. Not much longer, the species was found to have a subspecies Dendroaspis polylepis antinorii (Peters, 1873).[6] So now there was the nominate subspecies Dendroaspis polylepis polylepis (Black mamba) and a second subspecies Dendroaspis polylepis antinorii (Antinori's black mamba).[7] However, in 1896 Boulenger combined the species (Dendroaspis polylepis) as a whole with the eastern green mamba, Dendroaspis angusticeps, and they were considered a single species from 1896[8] until 1946, when Dr. Vivian FitzSimons split them into separate species again.[9][10]

Etymology

The snake's scientific name is Dendroaspis polylepis: Dendroaspis meaning "tree asp", and polylepis meaning "many scaled." The name "black mamba" is given to the snake not because of its body colour but because of its ink-black mouth.[1] It displays this physical attribute when threatened.[1]

Physical description

The adult black mamba's back skin colour is olive, brownish, gray, or sometimes khaki in colour. Young snakes are lighter in colour, appearing gray or olive green, but are not light enough to be confused with green mambas (D. angusticeps). Their underbody is cream-coloured, sometimes blended with green or yellow.[11] Dark spots or blotches may speckle the back half of the body and some individuals have alternating dark and light scales near the posterior, giving the impression of lateral bars (Spawls and Branch, 1995). The inside of the mouth is a dark blue to “inky” black in colour. The head is big but narrow and elongated, with a distinct shape of a "coffin".[12] It is a proteroglyphous snake, meaning it has non-movable, fixed fangs at the front of the maxilla. The eyes are dark brown to black, with a silvery-white to yellow edge on the pupils.[12] These snakes are strong but slender in body, adult specimens are 2.5 to 3 meters (8.2 to 9.8 ft) in length on average,[13][1] though some specimens have reached lengths of 4.3 to 4.5 meters (14 to 15 ft).[13][12] Black mambas weigh about 1.6 kilograms (3.5 lb) on average, though they can weigh up to 3.5 kilograms (7.7 lb).[1][14] The species is the second longest venomous snake in the world, exceeded in length only by the King cobra.[12] The snake has an average life span of 11 years in the wild.[1] Their smooth scales are at mid-body, in 23 to 25 (in some cases 21) rows (Branch, 1988; FitzSimons, 1970; Marais, 1985; Spawls and Branch, 1995).

Geographical range, habitat, and status

Although a large, diurnal, and "notorious" snake, the distribution of the black mamba (D. polylepis polylepis) is the subject of much confusion in research literature, indicating the poor status of African herpetological zoogeography.[15] However, the distribution of the black mamba in eastern Africa and southern Africa is well documented. Pitman (1974) gives the following range for the species' total distribution in Africa: northeast Democratic Republic of the Congo, southwestern Sudan to Ethiopia, Eritrea, Somalia, Kenya, eastern Uganda, Tanzania, southwards to Mozambique, Swaziland, Malawi, Zambia, Zimbabwe and Botswana to KwaZulu-Natal in South Africa, and Namibia; then northeasterly through Angola to the southeastern part of the Democratic Republic of Congo.[15][16] According to CITES, the species is also found in Lesotho, Rwanda, and Djibouti.[17] The black mamba is not commonly found above altitudes of 1,000 metres (3,300 ft), although the distribution of black mamba does reach 1,800 metres (5,900 ft) in Kenya and 1,650 metres (5,410 ft) in Zambia (Spawls, 1978).[15] The black mamba was also recorded in 1954 in West Africa in the Dakar region of Senegal.[15] However, this observation, and a subsequent observation that identified a second specimen in the region in 1956, have not been confirmed and thus the species' distribution in West Africa is inconclusive.[15] The black mamba's western distribution contains gaps within the Central African Republic, Chad, Nigeria and Mali. These gaps may lead physicians to misidentify the black mamba and administer an ineffective antivenom.[15] Antinorii's black mamba occurs only in eastern Africa and is found in Somalia, Ethiopia, Eritrea, northern Kenya, and northeastern Uganda.[6]

Habitat

Both subspecies of the black mamba have adapted to a variety of climates ranging from savanna, woodlands, farmlands, rocky slopes, dense forests and even humid swamps.[15] The grassland and savanna woodland/shrubs that extend all the way from southern and eastern Africa to central and western Africa, eastern and southern Africa are the black mamba's typical habitat.[15] The black mamba prefers more arid environments such as semi-arid dry bush country, light woodland, and rocky outcrops (Pitman, 1974).[15] This species likes areas with a lot of hills as well as riverine forests. Black mamba's also often make use of abandoned termite mounds and hollow trees for shelter (Pitman, 1974). The abandoned termite mounds are especially used when the snake is looking for somewhere to cool off as the mounds are sort of a "natural air-conditioning" system. The structure of these mounds is very complex and elaborate. They have a network of holes, ducts, and chimneys that allow air to circulate freely, drawing heat away from the nest during the day - though without taking too much valuable moisture - while preventing the nest cooling too much at night.[16] However, as a territorial species the black mamba and so will always return to their territory.

Environmental encroachment

The sugarcane fields that dominate the habitat of the black mamba.

Although the black mamba is not an endangered or threatened species by any means, its environment is rapidly diminishing in some parts of its range in Africa. In Swaziland alone, 75% of the population is employed by subsistence farming.[18] Because of agricultural encroachment on the black mamba's habitat, the snake is commonly found in sugarcane fields. The black mamba will climb to the top of the sugarcane to bask in the sun and possibly wait for prey. The majority of human attacks occur in the sugarcane fields of east and southern Africa in which are employed thousands of workers for manual labour, as cane growing is not a highly mechanised industry. This encroachment on the snake's territory contributes to potentially dangerous human contact with these highly venomous snakes.[1]

Fear, myths, and killings of black mambas

Another problem which this species faces is human persecution as it is feared throughout the continent of Africa. Although it would much rather avoid confrontation and flee from any perceived threat, the black mamba can be extremely aggressive and if badgered long and hard enough or if cornered with no escape, it will stand its ground and display fearsome viciousness and unparalleled aggression - aggression and ferocity unseen in any other snake. No other snake in the continent is as loathed, and yet respected and feared at the same time. For this reason, many black mamba's are killed right where they are spotted by villagers.[19][20] It usually requires a group of people to kill it as it is very fast and agile, striking in all directions while a third of its body is 3-4 feet above the ground. Villagers will use rocks, big knifes, saws, or big pieces of wood to either chop the snake, crush it, or kill it in some fashion. The black mamba will sometimes bite one or two of the villagers before being killed itself (in Swaziland, seven men were bitten by a single black mamba they were attempting to kill and all seven men died, the last one to die died ~90 minutes post-envenomation).[21] This is common in some parts of its geographical range. The deep fear of this snake stems not only from its reputation for aggression, speed, and venom toxicity, but it also stems from stories and legends that have been passed down from one generation to the next.[20] It's claimed that the mere mention of its name can cause fear, anxiety, or panic attacks in some people. The indigenous people of Africa that live in the black mamba's range share stories of how this snake has been seen chasing away herds of Cape buffalos, wildebeests, and even chasing away humans. Magical abilities have even been attributed to it, which has added to the myth, mystery, and fear of the black mamba. Other stories include black mamba's biting and killing full grown bull elephants, which are unverified. However, there is a scientifically verified record of a fully grown adult female elephant that died due to black mamba envenomation in 2006.[22] Many other legendary stories have been attributed to this species, most are myths, some are unconfirmed and only a very few of them are said to be "possible" based upon what we know of this species' behavior.[23]

Behaviour

A black mamba climbing a branch, in London Zoo.

The black mamba uses its speed to escape threats, not to hunt prey.[1] It is known to be capable of reaching speeds of around 20 kilometers per hour (12 mph), traveling with up to a third of its body raised off the ground.[1] Over long distances the black mamba can travel 11 to 19 kilometers per hour (6.8 to 11.8 mph), but in short bursts it can reach a speed of 16 to 20 kilometers per hour (9.9 to 12.4 mph), and it's even been recorded at speeds of 23 kilometers per hour (14 mph) [24] making it the fastest land snake in the world.[25] The black mamba is a territorial snake, having a favoured home usually in an abandoned termite mound, a hollow tree, a hollow log, or a rock crevice. It will actively defend its territory very aggressively.[26][27] It is a shy and secretive snake in general; it always seeks to escape when a confrontation occurs, unless cornered in which case the black mamba can put up a fearsome display of defense and aggression.[1] When cornered it mimics a cobra by spreading a neck-flap, exposing its black mouth, it lifts a third of its body up off the ground, and hisses.[1] If this endeavor to scare away the attacker fails, the black mamba will strike repeatedly.[1] The black mamba will readily attack. In fact, many snake experts have cited the black mamba as the world's most aggressive snake, noting tendency to actively attack without provocation (B. Johnson, July 13, 2000; Hunter, 1998).[28]

The black mamba is a diurnal snake. Although its scientific name seems to be indicative of tree climbing, the black mamba is rarely an arboreal snake.[25] These snakes retreat when threatened by predators, but they will defend their territory and aggressively try to ward of any predator which corners it, including humans.[27][24]

Hunting and prey

As stated, the black mamba is diurnal. It is an ambush predator that will wait for prey to get close.[24] If the prey attempts to escape, the black mamba will follow up its initial bite with a series of strikes.[24] When hunting, the black mamba has been known to raise a large portion of its body off the ground and slither quickly through their habitat in search of prey.[24] The black mamba will release larger prey after biting it, but smaller prey, such as birds or rats, are held onto until the prey's muscles stop moving.[24] They have been known to prey on bushbabies, bats, and small chickens.[9] The black mamba feeds almost solely on warm-blooded animals, such as birds and small mammals including hyraxes and various rodents. They have also been occasionally seen preying on other snakes like the puff adder and Cape cobra.[29] After ingestion, powerful acids digest the prey, sometimes within 8 to 10 hours (Branch, 1988; FitzSimons, 1970).[11]

Communication and Perception

Black mamba's shows little deviation from the common methods of communication and perception found in snakes. They use their eyesight mainly for detection of motion, and sudden movements will cause them to strike. The tongue is extended from the mouth to collect particles of air, which are then deposited in the vomeronasal organ on the roof of the mouth, which acts as a chemosensory organ. They have no external ears, but are quite adept at detecting vibrations from the ground. Like many snakes, when threatened, they will display aggression with a set of signals warning of the possibility of attack.[11]

Venom

Although the venom of the black mamba consists mainly of potent neurotoxins,[30] it also contains cardiotoxins.[27][31][32] With a LD50 range of 0.05 mg/kg—0.32 mg/kg ( Ernst and Zug et al. 1996), the black mamba's venom's average LD50 is 0.185 mg/kg ( Ernst and Zug et al. 1996), making it virulently toxic and one of the most venomous land snakes in the world.[33][34] Based on LD50 toxicology studies, this species is the seventh most venomous land snake in the world.[35][36][33] The venom is so virulently toxic and rapid-acting, even the largest land mammal can't live through a bite from this species. In 2006, a fully grown adult female elephant named Eleanor, who was a matriarch of an entire herd and was between 40 and 48 years of age[37] and weighed over 7,500 pounds, was bitten and subsequently killed by a black mamba at Samburu National Reserve in Kenya.[22] Scientists in the field shot footage of Eleanor's herd calling out in distress and making desperate attempts to get the dying elephant back onto her feet, but Eleanor succumbed to the venom and died. To date, this is the only known case in which a snake bit and killed an adult elephant.[22] For photos and more info on the life of Eleanor the elephant go here.

Although only 10 to 15 mg[38] is deadly to a human adult, its bite delivers about 100–120 mg of venom on average[38], but they can deliver up to 400 mg of venom in a single bite[38]. It is reported that before the antivenom was widely available, the mortality rate from a bite was 100%.[27][39][40][41][42][1][34] Black mamba bites can potentially kill a human within 20 minutes or less[43][44][38][45] depending on the nature of the bite and the area bitten, but death usually occurs after 30–60 minutes on average, sometimes even taking up to three hours. British wildlife enthusiast Nathan Layton was bitten in Hoedspruit, a small city near Kruger National Park, by a juvenile black mamba and died in less than 30 minutes after being bitten. Nearby ambulance personnel were called to the scene, but Mr. Layton was already dead by the time they had arrived.[46] The fatality duration and rate depend on various factors, such as the health, size, age, psychological state of the human, the penetration of one or both fangs from the snake, amount of venom injected, location of the bite, and proximity to major blood vessels.[1] The health of the snake and the interval since it last used its venom mechanism is also important. Presently, there is a polyvalent antivenom produced by South African Institute for Medical Research (SAIMR) to treat all black mamba bites from different localities.[34]

If bitten, neurological, respiratory, and cardiovascular symptoms rapidly begin to manifest, usually within five minutes or less. Common symptoms for which to watch are rapid onset of dizziness, drowsiness, coughing or difficulty breathing, and erratic heartbeat.[34] Other common symptoms which come on rapidly include neuromuscular symptoms, shock, loss of consciousness, hypotension, pallor, ataxia, excessive salivation (oral secretions may become profuse and thick), limb paralysis, nausea and vomiting, ptosis, fever, and very severe abdominal pain. Local tissue damage appears to be relatively infrequent and of minor severity in most cases of black mamba envenomation. Edema is typically minimal.[34] In cases where the victim has received larger amounts of venom than average (over 200 mg +) or the venom was delivered right into a vein, death can result within as little as 10 minutes[1][45] from respiratory or cardiac arrest.[34] This is also true if the victim is bitten in the face or chest area, as a black mamba can rear up around one-third of its body from the ground which puts it at about four feet high. When warding off a threat, the black mamba delivers multiple strikes, injecting large amounts of virulently toxic venom with each strike, often landing bites on the body or head, unlike other snakes. The venom of this species has also been known to cause permanent paralysis if treatment with antivenom was delayed.[34] Death is due to suffocation resulting from paralysis of the respiratory muscles.[34]

Many herpetologists, including South African-born herpetologist Austin Stevens, regard the black mamba as one of, if not the deadliest and most feared snake in the world[47] due to various factors including the toxicity and high yield of its venom, the fact that untreated bites have a mortality rate of 100%, its high level of aggression, its speed, agility, size, and other factors.[48][45] Nevertheless, attacks on humans by black mambas are rare, as the snakes usually avoid confrontation with humans and their occurrence in highly-populated areas is not as common compared to many other African species of venomous snakes.

Toxins

Mamba venom is made up mostly of dendrotoxins (dendrotoxin-k - "Toxin K"[49], dendrotoxin-1 - "Toxin 1"[50], dendrotoxin-3 - "Toxin 3"[51], dendrotoxin-7 - "Toxin 7"[51], among others), fasciculins, and calciseptine[52]. The dendrotoxins disrupt the exogenous process of muscle contraction by means of the sodium potassium pump. Toxin K is a selective blocker of voltage-gated potassium channels[53], Toxin 1 inhibits the K+ channels at the pre and post-synaptic level in the intestinal smooth muscle. It also inhibits Ca2+-sensitive K+ channels from rat skeletal muscle‚ incorporated into planar bilayers (Kd = 90 nM in 50 mM KCl)[54], Toxin 3 inhibits M4 receptors, while Toxin 7 inhibits M1 receptors.[51] The calciseptine is a 60 amino acid peptide which acts as a smooth muscle relaxant and an inhibitor of cardiac contractions. It blocks K+ induced contraction in aortic smooth muscle and it blocks spontaneous contraction of uterine muscle and portal vein.[55][38] The venom is highly specific and virulently toxic. In an experiment, the death time of a mouse after subcutaneous injection of some toxins studied is around 7 minutes. However, a black mamba venom can kill a mouse after 4.5 minutes.[45]

Predators

The Yellow mongoose is the major predator of young mambas and eggs

The black mamba has few natural predators[9] and the main threat is humans and birds of prey.[9][14] Another noticeable snake hunter is the mongoose. Mongoose have resistance which is caused by mutations in their nicotinic acetylcholine receptor to many snake toxins, such as alpha-bungarotoxin and alpha-cobratoxin as their alpha-subunits do not bind with these toxins very well, unlike other animals.[56] So they can survive bites even when the venom dosage which is fatal to other animals is injected into them.[56] But a study suggested that dendrotoxins which is the main component of mambas' venom can bind to the alpha subunits more effectively.[57] However, mongooses do occasionally prey on mambas but they as other predators mainly look for young snakes since they can be killed with ease. Cape file snakes have also been observed predating on young black mambas.[9] In addition, a 1.9 meter black mamba was found to be swallowed by a brindle bass.[9]

Gallery

  • Black mamba at Wilmington's Serpentarium
    Black mamba at Wilmington's Serpentarium
  • Close-up of a black mamba's head
    Close-up of a black mamba's head
  • A black mamba at the St Louis zoo
    A black mamba at the St Louis zoo

References

  1. ^ a b c d e f g h i j k l m n o p "Black mamba". National Geographic Society. Retrieved 2010-03-12.
  2. ^ The Reptile Database. www.reptile-database.org.
  3. ^ Dendroaspis polylepis (black mamba)
  4. ^ Reputation of the Black Mamba
  5. ^ Myths surrounding the Black Mamba
  6. ^ a b genus=Dendroaspis&species=polylepis&search_param=%28%28taxon%3D%27Elapidae%27%29%29 Reptile Database (Dendroaspis polylepis)
  7. ^ IMMEDIATE FIRST AID - Antinorii's Black Mamba
  8. ^ Boulenger, G.A. 1896. Catalogue of the Snakes in the British Museum (Natural History), Volume III. London. p. 437.
  9. ^ a b c d e f Haagner, G.V; Dr. Morgan (1993). "The maintenance and propagation of the Black mamba Dendroaspis polylepis at the Manyeleti Reptile Centre, Eastern Transvaal" (PDF). International Zoo Yearbook. Zoological Society of London. Retrieved 2010-05-19.{{cite web}}: CS1 maint: multiple names: authors list (link)
  10. ^ Günther, A. (1864). Report on a Collection of Reptiles and Fishes made by Dr. Kirk in the Zambesi and Nyassa Regions. Vol. 1864. London, England: Proc. Zool. Soc. London. pp. 303–314.
  11. ^ a b c Marais, Johan. Snake versus man: A guide to dangerous and common harmless snakes of southern Africa. Braamfontein, Johannesburg (South Africa): Macmillan South Africa. ISBN 0869542672. {{cite book}}: Unknown parameter |Year= ignored (|year= suggested) (help)
  12. ^ a b c d Mattison, Chris (1987-01-01). Snakes of the World. New York: Facts on File, Inc. p. 164.
  13. ^ a b Devenomized - Black Mamba
  14. ^ a b Hallowell, Edward (1844). Description of new species of African reptiles. Vol. 2. Philadelphia, USA: Proceedings of the National Academy of Sciences (Stanford University's Highwire Press). pp. 169–172.
  15. ^ a b c d e f g h i "On the Distribution of the Black Mamba (Dendroaspis polylepis) in West Africa". Journal of Herpetology. 17 (2): 186–187. 1983. {{cite journal}}: Cite uses deprecated parameter |authors= (help); Unknown parameter |month= ignored (help)
  16. ^ a b Snakes Uncovered (D. polylepis Information)
  17. ^ CITES species finder - Black Mamba
  18. ^ "UNDP: Human development indices – Table 3: Human and income poverty (Population living below national poverty line (2000-2007))" (PDF). United Nations Development Programme. 28 November 2008. Retrieved 29 December 2009.
  19. ^ BBC Knowledge (Black Mamba)
  20. ^ a b Kruger National Park - Black Mamba
  21. ^ All Black Mamba Info
  22. ^ a b c Daily Mail - Snake kills Elephant
  23. ^ Black Mamba myths Debunked
  24. ^ a b c d e f Richardson, Adele (2004). Mambas. Mankato, Minnesota: Capstone Press. p. 25. Retrieved 2010-05-19.
  25. ^ a b Maina, J.N (1989-12). "The morphology of the lung of the black mamba Dendroaspis polylepis". The Journal of Anatomy. PMC 1256818. {{cite journal}}: Check date values in: |date= (help)
  26. ^ Botswana Black Mamba's
  27. ^ a b c d Mitchell, Deborah (September 2009). The Encyclopedia of Poisons and Antidotes. New York, USA: Facts on File, Inc. p. 324. ISBN 0816064016.
  28. ^ Venomous Snakes and Snakebites
  29. ^ Burton, Robert (2002). International Wildlife Encyclopedia: Leopard - marten. USA: Marshall Cavendish. p. 3168. ISBN 0761472770.
  30. ^ [cogs.csustan.edu/~tom/bioinfo/groupwork/cobra/cobra-venom.ppt Neurotoxins in Snake Venom]
  31. ^ "Putative cardiotoxicity of the venoms of three mamba species". Journal of Wilderness and Environmental Medicine. 7 (2). May 1996. PMID 11990104. {{cite journal}}: Cite uses deprecated parameter |authors= (help)
  32. ^ Toxipedia (Black Mamba)
  33. ^ a b LD50 Menu
  34. ^ a b c d e f g h Davidson, Terence. "IMMEDIATE FIRST AID". University of California, San Diego. Retrieved 2010-05-12.
  35. ^ Zug, George R. (1996). Snakes in Question: The Smithsonian Answer Book. Washington D.C., USA: Smithsonian Institution Scholarly Press. ISBN 1560986484.
  36. ^ "LD50 Menu". Retrieved 2010-04-21.
  37. ^ Life of Eleanor the Elephant
  38. ^ a b c d e "Black Mamba Biology". Retrieved 13/09/2011. {{cite web}}: Check date values in: |accessdate= (help)
  39. ^ National Geographic - Black Mamba
  40. ^ Mortality rate 100%
  41. ^ Nature-Black Mamba
  42. ^ Black Mamba Intro
  43. ^ National Geographic - Black Mamba
  44. ^ Death of Nathan Layton
  45. ^ a b c d Strydom, Daniel (1971-11-12). "Snake Venom Toxins" (PDF). The Journal of Biological Chemistry. Retrieved 2010-04-24.
  46. ^ British wildlife student dies in front of girlfriend minutes after being bitten by black mamba snake - Mail Online
  47. ^ Manbir Online - Snakes
  48. ^ Austin Steven's Official Website
  49. ^ "[Nuclear magnetic resonance solution structure of dendrotoxin K from the venom of Dendroaspis polylepis polylepis.]". Journal of Molecular Biology. 234 (3): 735–50. 1993. PMID 8254670. {{cite journal}}: Cite uses deprecated parameter |authors= (help); Unknown parameter |month= ignored (help)
  50. ^ "[Potassium channels and epilepsy: evidence that the epileptogenic toxin, dendrotoxin, binds to potassium channel proteins.]". Epilepsy Research Supplement. 4: 263-73. 1991. PMID 1815606. {{cite journal}}: Cite uses deprecated parameter |authors= (help)
  51. ^ a b c Rang, H. P. (2003). Pharamacology. Edinburgh: Churchill Livingstone. p. 139. ISBN 0-443-07145-4.
  52. ^ "[Calciseptine, a peptide isolated from black mamba venom, is a specific blocker of the L-type calcium channel.]". Proceedings of the National Academy of Science of the United States of America. 88 (6): 2437–2440. 15 March. {{cite journal}}: Check date values in: |date= and |year= / |date= mismatch (help); Cite uses deprecated parameter |authors= (help); Unknown parameter |PMCID= ignored (|pmc= suggested) (help)
  53. ^ "[Nuclear magnetic resonance solution structure of dendrotoxin K from the venom of Dendroaspis polylepis polylepis.]". Journal of Molecular Biology. 234 (3): 735–50. 1993. PMID 8254670. {{cite journal}}: Cite uses deprecated parameter |authors= (help); Unknown parameter |month= ignored (help)
  54. ^ "[Potassium channels and epilepsy: evidence that the epileptogenic toxin, dendrotoxin, binds to potassium channel proteins.]". Epilepsy Research Supplement. 4: 263-73. 1991. PMID 1815606. {{cite journal}}: Cite uses deprecated parameter |authors= (help)
  55. ^ Calciseptine study
  56. ^ a b Mongoose Venom Resistance
  57. ^ Conti-Tronconi BM, Raftery MA. "Nicotinic acetylcholine receptor contains multiple binding sites: evidence from binding of alpha-dendrotoxin". 83 (17): 6646-50. PMID 3462717. {{cite journal}}: Cite journal requires |journal= (help)

External links

Media related to Dendroaspis polylepis at Wikimedia Commons

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