Carnivorous Plants - The Royal and Linnean Societies

Hey everyone, I'm John! With my trip to London and Cambridge officially underway, I’ll be visiting a few sites related to the scientific study of carnivorous plants, and examining their place in plant conservation and the public imagination. There are roughly 1,000 plant species spread across every continent except Antarctica able to attract, capture, and digest animal prey; a suite of adaptations that have evolved independently at least seven times. Carnivorous plants are by no standard the most important or impactful organisms on the planet, but within the plant kingdom, I believe they represent Darwinian principles taken to their most elegant extremes.

Disclaimer: I took WAY too many pics
of plants on this trip.

On a physical and chemical level, they are uniquely beautiful and offer insights into how the way we understand the natural world has changed over the past several hundred years. Evolutionarily, these plants have partnered with us mammals (from shrews to bats) in a number of complex symbiotic relationships, the dangerous simplicity of their traps has attracted the attention of modern engineers, and their biochemistry has opened new windows of understanding into our own evolution as mammals. Over the course of my trip, I hope to piece together a more complete picture of how plant carnivory has been studied and what exactly about these plants has secured their position as organisms of timeless fascination for the botanically inclined.

I hit the ground running after my morning red-eye landed in Heathrow (from Vietnam -- the jet lag was real) by checking into my hostel and heading over to my first archive visit at the Royal Society. It’s about 40 minutes away from my hostel on foot, but I was happy to cross paths with several London landmarks on my way there. From Westminster Abbey and Big Ben (sadly under renovation) to Buckingham Palace and St. James’s Park, I was able to cross quite a few sights off my bucket list. Unfortunately, the first few days of my trip I was getting over some food poisoning, so most of my time outside of archives was spent in bed.

Buckingham Palace!

The exterior of the building was a bit more modest than I had expected, but after checking in and receiving my reader's pass, I was eager to check out the portraits of famous fellows and the unique letters and books on display outside of the small reading room. Of the materials I looked at during the visit most were responses to work on carnivorous plants submitted for publication by the society. Of these, nothing yielded anything super surprising. However, I was happy to find two artifacts related to Darwin. The first was a certificate of candidacy for election to the society, noting the achievements of Darwin’s son Francis in studying several species of carnivorous plants (largely building on his father's work), signed by his father and many reputable members of the society. The second object was an early mint of the Darwin Medal, awarded by the Royal Society on alternate years since 1890 when it was given to Alfred Russel Wallace. The medal prominently features many plants Darwin worked with later in his life, with a Venus fly-trap at its center. It was cool to explore a place connected to so many legendary men and women of science, but I felt my trip to the Linnean Society the following day was more successful.

There were plenty of priceless books laying around the Royal Society,
but Newton's heavily annotated De occulta philosphia was my personal favorite.

The Linnean staff was incredibly kind and helpful, and I actually ended up looking at a lot more than I had intended to that day. I was especially excited to find a lot of material on pre-Darwinian ideas about plant carnivory. The correspondence of John Ellis, who was the first European botanist to study and illustrate the Venus Fly Trap (Dionaea muscipula) in any sort of depth, was particularly insightful. I was given two huge volumes of undigitized letters, drawings, and miscellaneous manuscripts chronicling Ellis’ interactions with a diverse cast of friends and colleagues. From the intimate letters of a sister, Martha, fretting over her brother’s travels in America to lively discussions with Benjamin Franklin on the history of coffee, I spent some time trying to understand what this man’s life was like. A 1768 letter I found from David Skine to Ellis includes a critical observation about the nature of these trapping mechanisms.

One of the first recorded mentions of the Venus Fly-Trap!

Skine claims that they are directly useful to the plant in extracting nutrients from animal life; essentially in the same way that us animals do to plants. We now know that plants consume other living things for very different reasons (for mineral vs caloric nutrition). Presumably, this correspondence also pertained to Ellis’ 1769 letter to Linneaus describing these plants and their carnivorous habits. Skine seems to warn about Linneaus’ potential stubbornness on the matter of plant carnivory. Just a few years after Ellis described the properties of Dionaea to Linnaeus, the father of modern taxonomy issued a statement thoroughly denying any possibility of plant carnivory. This is just one of many examples of scientists exploring the notion of plant carnivory, but following Linnaeus’ public opposition few paid much attention to these claims until Darwin decided to devote himself to the subject. It was fascinating to read a first-hand reaction to a plant that so fundamentally violated what was known about the natural world at this time.

Later that evening I attended a public lecture held at the society. As an official meeting, I got to observe some of the formalities and even saw two new fellows sworn in! Then, Dr. Victoria Johnson of Columbia University discussed her book “American Eden: David Hosack, Botany, and Medicine in the Garden of the Early Republic.” It serves as a culmination of her many years researching the man who founded the first public botanical garden in America. The trusted doctor and friend of both Alexander Hamilton and William Burr, you may recognize his name from the infamous dueling scene between the two in the musical Hamilton. Otherwise, this visionary botanist and surgeon has been mostly lost in the backdrop of early American history, and the world-class Elgin Botanic Garden he founded in New York in 1810 is now buried beneath present-day Rockefeller Center. While not directly related to carnivorous plants, the talk definitely helped me understand the bigger picture of botany in America during the time that Ellis would have been traveling and studying the plants of the "early republic." At the wine reception held afterward, I ended up discussing my Rosenkrantz trip with several of the fellows who have an interest in botany. I was honestly ecstatic to find people as enamored by carnivorous plants as I am and left the society that evening with a now growing list of book recommendations and contacts eager to help me in my research. Easily the highlight of the trip so far!

The Linnean Society -- Exterior and interior.