Are snakes poisonous or venomous?

In an article published on November 13, 2023, titled ‘Nigeria’s Most Potent Snakes: An In-depth Introduction’ on this website, a particular statement—’…So, snakes are venomous, not poisonous’—stirred confusion among readers. This led to a common question: ‘Are snakes poisonous or venomous?’ This article aims to provide a comprehensive answer to this query, delving into the distinctions between poison and venom.

To correct the misconception and provide a thorough understanding of the difference between poison and venom, it’s essential to understand how toxins are delivered in organisms. Poisonous organisms, such as certain amphibians like poison dart frogs, release toxins when touched or ingested. On the other hand, venomous creatures inject venom via specialized structures like fangs or stingers. Therefore, when discussing snakes, it’s more accurate to describe them as venomous rather than poisonous.

Snakes, by and large, are not poisonous but venomous. Poison and venom differ mainly in how they are delivered into the body.

• Poison, typically ingested, inhaled, or absorbed through the skin, has small chemical molecules that can easily pass through the skin. Poisonous snakes primarily use toxins for defensive purposes.
• Venom: Injected into the body mechanically, often through fangs, as venom molecules are too large to be absorbed. Venomous snakes deploy venom for both hunting and defence.

In everyday language, venom is sometimes referred to as poison, and animals that possess venom are sometimes described as poisonous. For instance, venomous snakes are often called poisonous. However, if an organism bites a person and the person dies, then the organism is considered venomous. On the other hand, if a person bites an organism and dies, then the organism is considered poisonous. While the majority of snakes fall under the venomous category, some exceptions blur the distinction between poison and venom. Certain species, such as the keelback and garter snakes, display characteristics of both venomous and poisonous organisms. Keelback snakes, for example, obtain toxins from their prey, while common garter snakes retain toxins in their bodies from consuming specific prey items.

Venom

Snake venom is a complex mixture of proteins and enzymes produced by specialized glands. It varies among species and is tailored to suit different purposes, such as hunting or defence. The composition of snake venom can include several types of toxins, each with distinct effects:

1. Hemotoxins: These toxins target the blood and circulatory system, causing symptoms such as bleeding, organ damage, and tissue destruction. They lead to conditions like haemorrhage, where blood escapes from blood vessels into surrounding tissues, potentially causing severe internal bleeding.
2. Neurotoxins: These toxins affect the nervous system, interfering with the transmission of nerve signals. Symptoms include paralysis, muscle weakness, and respiratory failure. In severe cases, neurotoxins can lead to complete paralysis, potentially causing death due to respiratory arrest.
3. Cytotoxins: These toxins damage or kill cells, disrupting cellular structures and functions. Symptoms may include inflammation, tissue necrosis, and organ dysfunction. Cytotoxins cause damage at the cellular level, contributing to the overall toxicity of snake venom.
4. Myotoxins: These toxins target muscle tissue, causing muscle degeneration, pain, swelling, and weakness. They impair muscle function and mobility, potentially leading to rhabdomyolysis, a condition where damaged muscle cells release toxic substances into the bloodstream, potentially causing kidney damage or failure.

Understanding these different types of toxins found in snake venom provides insight into how snakes employ a variety of strategies to immobilize and incapacitate their prey or defend themselves against predators.

Recognizing the importance of snakes in ecosystems highlights their ecological significance. Venomous snakes contribute to controlling populations of rodents and other small animals, thus maintaining the balance of local ecosystems and influencing biodiversity. It’s crucial to clarify the distinction between poisonous and venomous organisms, as well as to appreciate the anatomy and function of snake venom. This knowledge not only corrects misconceptions but also fosters a deeper understanding of the ecological roles of these fascinating creatures.