Animal tube | The deadliest natural weapon employed in the animal kingdom, venom has independently evolved in creatures as diverse as jellyfish, insects, snakes, and even mammals. Scientists from around the globe show how evolution adapted venom to fit the needs of the animals who wield it. Injecting venom into samples of his blood, the show demonstrates how the world’s deadliest snake, the inland taipan, has converted the building blocks of its body into lethal toxins. Host will introduce us to the cone snail, pound-for-pound the most toxic creature in the world, able to continually update its chemical cocktails with the help of the world’s fastest-evolving genes, guaranteeing the creatures stay one step ahead of their is the general term referring to any variety of toxins used by certain types of animals that inject it into their victims by the means of a bite, sting or other sharp body potency of different venoms varies; lethal venoms are often characterised by the median lethal dose (LD50, LD50, or LD-50), expressed in terms of mass fraction (, milligrams of toxin per kilogram of body mass), that will kill 50% of victims of a specified type (, laboratory mice).DiversityInvertebratesVenomous invertebrates include spiders, which use fangs – part of their chelicerae – to inject venom (see spider bite); and centipedes, which use forcipules – modified legs – to deliver venom; along with scorpions and stinging insects, which inject venom with a sting. In insects such as bees and wasps the stinger is a modified egg-laying device — the ovipositor. Many caterpillars have defensive venom glands associated with specialized bristles on the body, known as urticating hairs, which can be lethal to humans (, that of the Lonomia moth), although the venom’s strength varies depending on the synthesize and employ an acidic venom (apitoxin) to cause pain in those that they sting to defend their hives and food stores, whereas wasps use a chemically different venom designed to paralyze prey, so it can be stored alive in the food chambers of their young. The use of venom is much more widespread than just these examples. Other insects, such as true bugs and many ants, also produce venom. At least one ant species (Polyrhachis dives) has been shown to use venom topically for the sterilisation of are many other venomous invertebrates, including jellyfish and cone snails. The box jellyfish is the most venomous jellyfish in the can also be found in some fish, such as the cartilaginous fishes — stingrays, sharks, and chimaeras — and the teleost fishes including onejaws, catfishes, stonefishes and waspfishes, scorpionfishes and lionfishes, gurnards, rabbitfishes, dragonets, surgeonfishes, scats, stargazers, weever, and are only a few species of venomous amphibians; certain salamandrid salamanders can extrude sharp venom-tipped reptiles most known to use venom are snakes, some species of which inject venom into their prey via venom is produced by glands below the eye (the mandibular gland) and delivered to the victim through tubular or channeled fangs. Snake venoms contain a variety of peptide toxins, including proteases, which hydrolyze protein peptide bonds, nucleases, which hydrolyze the phosphodiester bonds of DNA, and neurotoxins, which disable signalling in the nervous system. Snakes use their venom principally for hunting, though they do not hesitate to employ it defensively. Venomous snake bites may cause a variety of symptoms, including pain, swelling, tissue necrosis, low blood pressure, convulsions, hemorrhage (varying by species of snake), respiratory paralysis, kidney failure, coma and reptilesAside from snakes, venom is found in a few other reptiles such as the Mexican beaded lizard and gila monster, and may be present in a few species of monitor such reptile that was previously thought of as being nonvenomous is the Komodo dragon, Varanus komodoensis. It was then demonstrated through magnetic resonance imaging that the Komodo dragon possesses a mandibular gland with a major posterior compartment and five smaller anterior compartments. The scientists used mass spectrometry to show that the mixture of proteins present in the venom was as complex as the proteins found in snake to these recent studies investigating venom glands in squamates, lizards that were previously thought of as being nonvenomous are now being classified by some scientists as venomous because they possess a venom gland. This hypothetical clade, Toxicofera, includes all venomous squamates: the suborders Serpentes and Iguania and the families Varanidae, Anguidae, and mammals are also venomous, including solenodons, shrews, the slow loris, and the male platypus. | Video tube
Animal tube | Trace the Evolution of the Deadliest Natural Weapon in the Animal Kingdom [FULL DOCUMENTARY] | Video tube
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