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Probably the most dangerous snakes we work with are the African mambas, truly "death on speed". I consider the black mamba (Dendroaspis polylepis), together with the Australian coastal taipan (Oxyuranus scutellatus), the most dangerous snakes in the world. The black mamba has a reputation for being furious and fast, and does not like to be toyed with. This is the fastest snake in the world. On a hot day, a black mamba can reach 13 miles per hour (13 feet per second). That is scarily fast. Above all, they have a very toxic venom and can bite multiple times in the blink of an eye. It is not unusual for somebody to get bitten two or three times before they have even noticed. There is no doubt that a black mamba bite can put a human's life at risk within minutes. The head of a black mamba is narrow, and has a black interior.
There is a famous saying about black mambas: "Why is the head of a black mamba shaped like a coffin? Because it can put you into one!". Nonetheless, these animals are fascinating. They are large, growing up to 4.5 meters in length, although their average size is below 3 meters. This makes the black mamba the second longest venomous snake in the world, after the king cobra. They have a slender and agile body, and, uniquely among the five species of mamba, they live on the ground most of their lives. These animals rule over the grasslands of Africa, which I have not yet had the pleasure to visit. I hope to go to Africa soon.
I used to keep a breeding pair of Western green mambas (Dendroaspis viridis) at home. They were one of my favorite snakes to keep, although they did require a large enclosure because of their size. Catching mambas requires even more focus and concentration than catching king cobras. Whereas king cobra behavior can be easily predicted, mambas are unpredictable. After they have been taken out of their cages, they can remain still for minutes, like a statue. But, appearances can be deceptive, once they are touched they can turn into Mr. Hyde as fast as a Lamborghini Diablo. Handling mambas in small rooms is never a good idea, because they are known to come close on purpose if they feel threatened. This has been interpreted as 'chasing' by many people, but I believe it is 'scarring off', not chasing. Stories of people 'chased' by mambas can be explained by the fact that mambas perhaps have adopted a defensive behavior that requires coming close to the threat quickly, which may have benefited mambas in their natural habitat, since their natural enemies include birds of prey.
Mamba venom is famous for containing dendrotoxins, 59 amino acid neurotoxins that block very specific subtypes of potassium channels in nerve membranes and thus facilitate neurotransmitter release. Interestingly, because of their potency and specificity for certain subtypes of the receptors, these toxins have been used as pharmacological tools to elaborate the structure-function of the channel proteins. This demonstrates that snake venom is not only useful for the pharmaceutical industry, but also for investigating the structure and function properties of general physiology. The venoms also contain fasciculin toxins (of the 'three-finger snake toxins' family), also unique to mamba venoms, that inhibit the workings of acetylcholinesterase, thus enhancing the effects of the neurotransmitter cholinesterase causing generalized muscle fasciculation ('muscle twitch').
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