Interesting Facts About Snake Venom
Snake venom is a complex mixture of various toxins. You cannot really group snake venom into the commonly used three classification of: Cytotoxic, Neurotoxic and Hemotoxic, as most snakes have a combination of the three as well as additional types of toxins not included in the commonly used terminology. Some toxins not mentioned very often are Nephrotoxins which effect kidney function, cardiotoxin which inhibits heart function to name a few. A few vipers venom can result in an immediate drop in blood pressure causing the patient to pass out, this does not go in line with the common types of venom we all grew up learning. An important factor to consider is that our bodies and the bodies of other animals have evolved defenses against the effects of venom. One of these defenses is to flush the site of the bite with lymphatic fluid in order to dilute the amount of venom in the limb that was bitten. This happens with any venomous bite from any venomous animal and is the reason you swell up after being stung by a wasp or bee for example. With back fanged snakes such as the Western Hog Nose Snake which is a popular pet, bites from this snake can cause a lot of swelling this does not mean this species of snake is dangerous to people. In general the venomous snakes that are most dangerous to us eat rodents as main source of their diet. There are exceptions to this. The reason for this is that venomous snakes began eating rodents and small mammals millions of years ago when snakes first appeared on the planet. As we are mammals the effects of venom and our defenses against it carried over to us from these early mammals. Snake venom has clever ways of increasing it’s effects. One of these is that certain snake venom increases blood pressure in order to allow the toxins to spread through the body quicker. A strange fact after all this talk about venom is that constriction is a much more effective way of killing prey. Animals that are constricted die much quicker than prey which is envenomated and does not require the extra energy to produce venom. A lot of snakes that eat fish, small frogs and tiny lizards are what I like to call “Gobbel and Go” predators these species simply grab their food and eat it while it is still wriggling, these snakes eat prey that cannot cause them harm and are not strong enough to escape. I breed North American Garter Snakes which are a prime example of this behavior.
Sometimes snake venom has different symptoms and effects on people than usual. For example a Black Mamba Bite causing localised swelling. One of the common ideas for this is due to the snake eating different prey in a specific area, thus causing symptoms which are different from the norm. New research suggests that this phenomenon is actually due to the a variations in a person’s immune system and how it reacts to the venom. This research suggests that the immune system plays a huge part in the treatment of venomous snake bites.
An interesting biological phenomenon is why venomous snakes have venom that is far more toxic than is required to kill their prey. The main function of snake venom is to kill prey, with a secondary function of defense. Maybe defending themselves is a huge part of the toxicity of a snakes venom and maybe more important than we think. Snakes can go months without eating and have no effects on their health, however the snake will not pass on it’s genes to the next generation if it is killed by predators Spitting cobras evolved at the exact time when early humans developed stone tools which they could throw. These cobras evolved this defense against humans who could kill them from a distance by being able to spit venom directly into the eyes of our ancestors which causes immediate pain in the eyes.