The Ancient Origin of Poisons
Source: https://www.britannica.com/topic/herbal and https://www.pbs.org/newshour/science/how-humans-learned-to-self-medicate-with-certain-plants-by-observing-animals
Knowledge of plant usage beyond food is a very ancient line of knowledge. Knowing which plants can reduce pain and fever, treat cough and congestion, or soothe nausea or diarrhea was critical to the survival of humans. Knowing which plants caused death or illness was also critical to the survival of humankind as well.
Source: https://archaeology.org/issues/january-february-2013/collection/top-10-2012-border-cave-beeswax-poison/top-10-discoveries-of-2012/
Direct evidence of poison is difficult to find since many of them are organic and tend to degrade over time. Evidence of complex poisons are even more ephemeral. Despite this, we can trace the use of poison in hunting as far back as 60,000-70,000 years ago, with evidence of ricinoleic acid found on a wooden applicator from 24,000 years ago, indicating the likely use of ricin.
By HediBougghanmi2014 - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=26602020
Ricin is a product of castor beans and is highly toxic in very small doses, though it can take hours to days to work because it prevents cells from making necessary proteins. The muscles near an injection site fail, eventually, the liver, kidneys, and spleen will cease functioning.
Source: https://www.cell.com/iscience/fulltext/S2589-0042(24)02663-4
Combining poisons to make one that would be more quickly effective, though, came much later. A 7,000 artifact that was excavated in South Africa in 1983 and studied in 2022 showed a combination of three plant-based poisons on arrowheads that were embedded into a femur bone of a bovine. The poison contained ricinoleic acid, probably indicating the presence of ricin, digitoxin from foxglove, and strophanthidin from the Strophanthus genus. Of these, only the Strophanthus plants grow near South Africa, though it is more prevalent in the rain forest regions of Africa. Foxglove is found around the Mediterranean, and castor oil plants are found around the Mediterranean and into India. This shows that there was also a robust trade network for these plants at the time, as well as the psychological development for complex understanding of the effects of plants and how they work together as poisons and likely as medicines.
By Kurt Stüber [1] - caliban.mpiz-koeln.mpg.de/mavica/index.html part of www.biolib.de, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=6516 and By SAplants - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=73677161
Digitoxin and Strophanthidin are both cardiac glycosides and interrupt the normal function of the electrical signals across the heart, leading to arrhythmias and death.
