NEBRASKAland Magazine is dedicated to outstanding photography and informative writing with an engaging mix of articles and photos highlighting Nebraska’s outdoor activities, parklands, wildlife, history and people.
Issue link: http://mag.outdoornebraska.gov/i/946863
44 NEBRASKAland • MARCH 2018 Snake Venom: Friend or Foe? A chemical cocktail of many uses. By Dan Fogell, Herpetologist T oxic, poisonous or venomous? Which word best describes those snakes which pass a nasty cocktail through hollow fangs? Toxins are substances produced by one organism that have deleterious effects on other organisms, so I guess snakes can be toxic. But nobody uses that word to describe snakes, so let's move on. Poisons are substances that can cause death or serious organ and tissue damage. Some snakes are definitely deadly, so poisonous is probably an acceptable word. But the question asked which word best describes those snakes. Venom is a toxin delivered by way of a biting or stinging apparatus. Fangs are biting tools for delivering a toxin. So if you chose venomous, you chose correctly. Honestly I've grown tired over the years of correcting people when they call snakes poisonous but they really mean venomous, so I no longer correct them (unless they are herpetologists who should know better). I can live with calling them poisonous, but if you really want to understand the difference, here's an easy way: poisons are ingested, venoms are injected. Mushrooms are poisonous. Bees and spiders are venomous ... and snakes ... well, some snakes are. So technically you'd have to eat a snake and experience harmful effects for that snake to be poisonous. Now that the terminology is out of the way, let's take a closer look at venom. Venom is a complex cocktail of chemicals, not all of which are toxins. Most of the chemicals are proteins, specifically enzymes. Many people classify venoms as either hemotoxic or neurotoxic. In general, hemotoxic venoms work by destroying blood cells and upsetting blood's ability to clot, and neurotoxic venoms negatively affect nervous system function in some way. There are also two other types of venom toxins: cytotoxins, which damage cellular structures, and cardiotoxins, which disrupt heart function. Any given venom can have one or all of these chemicals in varying proportions, but in most cases one toxin is dominant. Contrary to what you might think, venomous snakes do not produce venom just to kill humans. For the snake it has three potential functions, though not all venomous snakes take advantage of all three. First, it is a successful way to immobilize prey. This is the job of the toxins. Prey items differ depending on the snake species, so a snake's venom will contain the proper toxins for immobilizing its preferred prey. In fact, venoms can differ within the same species from different geographic areas, and even in Venom from this timber rattlesnake can be deadly if you are bitten, but it may also one day be used in medicine to treat human diseases and disorders. This drop of venom from a copperhead contains the enzyme contortrostatin, which can help prevent cancer cells from spreading throughout the body.