Hanson, Thor. The Triumph of Seeds: How Grains, Nuts, Kernels, Pulses, and Pips Conquered the Plant Kingdom and Shaped Human History. (2015) ISBN 9780465055999 pg xii-18, 161-177
As I read this deadly chapter by Thor Hansen on a dreary Vancouver-like morning, eating my smoothie riddled with berry seeds; I am amazed such tiny ‘seemingly’ harmless part of a plant could be a cold stone assassin.
I love the way Hansen starts off the chapter with a quote from Lewis Carroll’s Alice’s Adventures in Wonderland, “If you drink much from a bottle marked ‘poison’, it is almost certain to disagree with you sooner or later.”(Pg 161) He relates to this quote later on when he talks about the philosopher Nietzsche, “What does not kill me, makes me stronger.” (Pg 168) Some of the most poisonous seeds in small doses can be used for the treatment of diseases such as cancer, “The challenge, of course is twofold: finding the right dosage, and making sure the poisons don’t diffuse to other parts of the body.”(Pg 169) It’s pretty incredible that something so harmful can also be medicine.
I loved this reading from Hansen as he provides me with another conversation starter: the great umbrella assassination of the Cold War. He describes the mystery of what exactly killed Georgi Markov, who was poked with an umbrella on the fateful day of his death, “Only one group of poisons could have caused Markov’s deadly combination of symptoms so quickly: the poisons found in seeds.”(Pg 165) I thought this was a powerful sentence, the only poison strong enough to kill someone so quickly in such a small dose is not synthetic but from nature! It was discovered to be one of the most deadly seeds, the castor bean which is often used in the oil industry, it contains ricin, “Dispersed through the bloodstream, ricin sets off a wave of cell death so unstoppable that even scientific journals describe it with something like awe: ‘one of the most lethal substances known,’ ‘one of the most fascinating poisons,’ or simply ‘exquisitely toxic.'” (Pg 166) I have never even heard of this compound before, and as Hansen describes how easily it is obtained, it is a little unsettling. “People still grow them, [castor plants] for their oil and as an ornamental, and the plant has become a common roadside weed throughout the tropics.” (Pg 168) It’s even more disturbing how easy it is to extract the deadly ricin, with just an everyday coffee grinder.
Hansen guides us through his task of learning more about these dangerous seeds, talking to experts such as Dave Newman, Derek Bewley and Noelle Machnicki. We learn more about Hansen’s personal life when his close friend and coauthor dies from cancer, “In the end, no prescription was enough-Steve died a few short weeks before I defended my dissertation.” (Pg 172) He describes the irony of seed toxins being used for cancer treatment in the form of Warfarin.
Finally, Hansen discusses the question of how plants get their seeds dispersed if they are toxic to any seed dispersing animals, “After all, what better way to protect your seeds than to kill anything that tries to eat them?” (Pg 173) It’s great that the seeds are protected but how do they get dispersed? “…no matter how toxic they may have become, the plant must have also invented some way to disperse them.” (Pg 174) So most of these toxic seed bearing plants have special mechanisms to disperse them, such as the castor bean pods that pop open and seeds are flung into new spaces. Overall, I learned a lot from this chapter and I thoroughly enjoyed reading about the great mysteries of toxic seeds.