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Wednesday
Mar142012

Secret Venoms: Did You Know They Had it in Them? 

We're looking at evolution this week on Into the Wild. Ask someone to name a venomous animal and they'll probably say some kind of snake or frog. But there are a whole host of creatures which have seemingly kept their use of venoms and poisons quiet. So who are these secret assasins?

The Cuttlefish

Photo courtesy of Raw Processor

Now the cuttlefish may look harmless enough but this sea dwelling creature uses its beak to inject fast acting venom that attacks its victim’s nervous system. Fortunately for us the cuttlefish’s venom is not poisonous to humans.  

Centipede

The large claws on the head of these creepy crawlies carry venom glands which then transfer the venom to their victims. Centipedes are very common in the US and for the most part they are not fatal to humans. However, some of the large or giant species can be very dangerous to children. The Giant Redheaded Centipede is amongst one of the fiercest centipedes on the planet – sometimes growing up to 8 inches long. This species is fast moving and very aggressive and is definitely one to watch out for if you’re in the US.

Duck-Billed Platypus

This semi aquatic mammal, endemic to Australia and Tasmania is one of the few species of mammal that lays eggs rather than giving birth to live young and also one of the few to use venom. Mature male duck-billed platypuses are equipped with a horny spur at the rear of their ankles which is connected to a venom gland. No one is quite sure why the male platypus developed its venom and who the intended victim is. But fear not, scientists know that the venom is defiantly not deadly to humans. There is a theory that the venom may be used against competing males during the mating season as this is when the venom is at its most potent.

Millipedes

Closely related to centipedes – some species are known to emit poisonous liquid secretions or in some cases even cyanide gas through microscopic pores on their body. In some cases these substances can burn the exoskeleton of ants and other insect predators and can also damage the skin and eyes of other larger predators. However, these chemical secretions are fairly harmless to humans. At most they may cause a little pain, itching or cracked skin.

Gila Monster

Living in the USA and Mexico this guy’s claim to fame is that he is one of only two known venomous lizards in the world. The Gila Monster's teeth have grooves that conduct the poison, though strangely the venom is not transferred to the victim by an injecting bite but through chewing. The venomous bite of the Gila monster is used as a defensive measure rather than to attack prey and if threatened, these lizards will back away hissing with their mouth open, and if provoked they attack surprisingly quickly. Luckily the Gila Monster is rarely fatal to humans, although the bite can be extremely painful.

The Hooded Pitohui

Photo courtesy of markaharper1

Found in New Guinea, the Hooded Pitohui is no ordinary song bird. In fact the bird’s skin and feathers both contain a very powerful poison homobatrachotoxin which is the same poison found in South American dart frogs, though the birds are significantly less toxic. The birds, like the dart frogs, do not produce the poison but instead acquire it through their diet of choresine beetles. The poison is transferred to humans by merely touching or handling the bird and causes tingling and numbness but to cause any real harm one would have to eat a whole Hooded Pitohui.

Cone Snail

This snail has evolved a highly effective method of transferring venom into its victims. The cone snail is armed with a hollow, barbed harpoon loaded with venom which is a modification of the radula, an organ that acts as both the snail’s tongue and teeth. When the snail detects a prey animal nearby it is thought to release a paralysing chemical which allows it to engulf its victim with no struggle. It then contracts its muscles and fires its harpoon into the prey. This is one scary snail with larger species known to be responsible for 30 cases of human deaths.

Slow Loris

Image courtesy of snowflakegirl

The slow loris certainly doesn’t scream danger with that cute little face, but this little guy is actually the only mammal in the world that is both venomous and poisonous at the same time. The Slow Loris produces a toxin on the inside of its elbows which it then smears on its young to prevent them from being eaten. Not only this, but the slow loris will lick its elbows so that the poison is then in its mouth so it can deliver a venomous bite in self defence – what a clever fella. But watch out because people who have been bitten by the slow loris have reported it to be particularly painful with anaphylactic shock occurring in some cases.

By Hannah Jones

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