The Evolutionary Battle of Natural Chemicals: From Toxins to Therapies

The Evolutionary Battle of Natural Chemicals From Toxins to Therapies

Exploring the origins and functions of natural chemicals and their potential as transformative therapies

Humans have long relied on a variety of natural chemicals for different purposes, from spicing up our food to enduring pain. Recently, there has been a growing interest in psychedelics like psilocybin as potential treatments for mental health disorders. But why do plants, mushrooms, microbes, and even animals produce these chemicals with life-saving, life-enhancing, and even life-ending properties? As an evolutionary biologist, my research delves into the ancient battle between organisms and the chemicals they produce, shedding light on the potential risks and benefits of these compounds.

Unveiling the Chemical Arsenal

Examining five examples, we find that many natural chemicals with diverse uses have their origins in the ancient “war of nature.” Botulinum toxin, known as one of the deadliest natural toxins, is also the active ingredient in the anti-wrinkle drug Botox. Penicillin, a wonder drug, is derived from a chemical used by bread mold to fend off competing bacteria. Caffeine, the world’s most widely used psychoactive drug, is a potent insecticide produced by distantly related plants. Taxol, a poison made by yew trees to deter caterpillars, is a powerful anti-cancer drug. The venom of cone snails contains a painkiller called ziconotide.

Unintended Beneficiaries and Victims

Humans have unwittingly benefited from these chemical battles, but we have also fallen victim to them. The death of the author’s father from alcohol use disorder highlights the destructive power of ethanol, a toxin produced by brewer’s yeast. Similarly, monarch butterflies consume milkweed plants to acquire cardiac glycoside heart poisons, which they repurpose as a chemical shield against predators. These examples demonstrate how organisms use chemicals to protect themselves, sometimes at the expense of others.

The Rise of Psychedelics

Natural psychedelics, such as psilocybin, DMT, mescaline, and ergot alkaloids, have evolved independently in various organisms. Indigenous peoples around the world have long used these substances for medicinal and spiritual purposes. Recent studies are showing promising results in using psychedelics as transformative therapies for mental health disorders. However, understanding their origins and functions is crucial, as their evolution predates human existence.

Psychedelics as Chemical Weapons

Like other natural chemicals, psychedelics may serve as chemical weapons against enemies. Their bitterness acts as a defense mechanism, deterring animals from consuming them. For example, grasses in the genus Phalaris produce 5-Meo-DMT and DMT, which are unpalatable to grazing herbivores. Magic mushrooms produce high levels of psilocybin, which may disrupt the digestive tract and deter predators. While these chemicals have unintended effects in humans, their natural functions are critical to study.

Assessing the Potential of Psychedelics

To fully understand the safety and efficacy of psychedelics, rigorous clinical trials are necessary. While their potential as therapies is promising, the risks and unknown effects must be carefully considered, particularly for vulnerable populations. Lessons from nature remind us that natural does not always equate to safe or beneficial. As we explore the origins and functions of natural psychedelics, we must prioritize both basic research and clinical trials to maximize their potential benefits while minimizing harm.


The evolutionary battle between organisms and the chemicals they produce offers valuable insights into the potential risks and benefits of natural compounds. From toxins to transformative therapies, these chemicals have shaped the course of life on Earth. As we navigate our relationship with psychedelics, it is essential to approach them with scientific rigor and an understanding of their natural functions. By doing so, we can harness their potential as therapies while ensuring the safety and well-being of those who use them.