“When you go out into the woods, and you look at trees, you see all these different trees. And some of them are bent, and some of them are straight, and some of them are evergreens, and some of them are whatever. And you look at the tree and you allow it. You see why it is the way it is. You sort of understand that it didn’t get enough light, and so it turned that way. And you don’t get all emotional about it. You just allow it. You appreciate the tree.
The minute you get near humans, you lose all that. And you are constantly saying ‘You are too this, or I’m too this.’ That judgment mind comes in. And so I practice turning people into trees. Which means appreciating them just the way they are.”
- Ram Dass
1. On Ethnobotany
Mark J. Plotkin is an environmentalist, conservationist, scientist, and Amazonian explorer. As a world-famous enthnobotanist, he’s done Ayahuasca over 80 times because, as he likes to casually say, “It’s my job.”
Ethnobotany is the scientific study of the relationship between people and plants, usually referring to how and why a certain group of people use local or native plants for different purposes (medical, religious, etc). In the 1980s, Mark Plotkin got an opportunity, while taking night classes at Harvard, to accompany a grad student on an expedition to the north-east Amazon in search of the “man-eating” Black Caiman crocodile. He’s been studying the traditional indigenous plant use of Central and South American ever since.
My first introduction to his work was through his first book, Tales of a Shaman's Apprentice: An Ethnobotanist Searches for New Medicines in the Amazon Rain Forest. Visiting the Amazon rainforest 4 times in 5 years for a total of over 100 days, Plotkin lived with various tribes in order to understand and document their traditional uses of native plants. With humility and genuine curiosity, he creates trust and friendship among the people he encounters and finds his way into the private world of the healers and Shamans.
Plotkin was a guest on The Tim Ferriss Show last week. He discussed his relationship with psychedelics, the instances where traditional medicine has worked better than Western medicine, his work for and knowledge of rainforest conservation, and his new book The Amazon: What Everyone Needs to Know. It's such a good listen for so many reasons.
You can also check out Mark’s TED Talk on some of these same topics:
If enthnobotanical adventures get you as jazzed as they do me, here are two more entertaining, albeit fictitious, stories of scientists risking their lives in the pursuit of the botanical secrets of the Amazon:
The 1993 movie Medicine Man was a great find - Sean Connery is an enthnobotanist living with an indigenous Amazonian tribe in search of the cure for cancer. Lorraine Bracco is a loud, stubborn corporate scientist from the Bronx, sent down to check on what Connery’s character has been up to and why he’s stopped writing letters to his sponsors. Without being preachy, the film hits on deforestation and the white man’s responsibility when working with indigenous communities. Plus it's set exclusively in lush green rainforest, so this film was highly enjoyable for the anthropologist and conservationist in me. An underrated film in my opinion.
State of Wonder by Ann Patchett is a 2011 novel about American scientists deep in the Amazon rainforest, all in search of answers to different personal questions. The book is a page-turning adventure tale, one of life-saving plants and deadly natural threats, taking care to address the moral and ethical dilemmas that arise when people from the western world insert themselves into the lands and communities of indigenous people.
Another enthnobotanical non-fiction was written in 1996 by Wade Davis, titled One River: Explorations and Discoveries in the Amazon Rain Forest. I haven’t cracked open this 500+ pager yet, but I bought it because the author shared a mentor with Mark Plotkins - the one and only Richard Evan Schultz:
The man is so legendary that Plotkin's team created an interactive map of all his crazy botanically-focused adventures. More to come on this dreamboat in the future.
2. Trees - Living fast, Dying young, Threatening humans
A recent study from the University of Leeds confirms that across almost all tree species, fast growing trees have shorter lifespans.
This isn’t new information for specific species - Bristlecone Pine (Pinus longaeva) grow 1.8 inches in height each year and 1 inch in diameter per century and can live for over 4,000 years. Compare this to a Weeping Willow (Salix babylonica), which grows 5-8 feet per year but may only live 30-40 years.
Why do humans care?
Trees remove carbon from the atmosphere during the process of photosynthesis. Less carbon in the air means less heat-trapping greenhouse gases. While important in certain amounts, too much carbon in the atmosphere creates a warming of the globe. Living trees sequester carbon from the atmosphere and transform it into biomass (leaves, stems, flowers, etc.). Forests are considered carbon sinks if they sequester more carbon than they emit. Forests release more carbon then they absorb when they decay after dying (as a result of old age, fire, insect attack or other disturbance).
The current carbon cycle of the world’s forests results in a net uptake of carbon. Interestingly, this is thought to be a result of climate change - increases in carbon and temperature in cold regions around the world are thought to be the cause of stimulated tree growth. More trees growing than trees dying results in more uptake of carbon than release of carbon. Our society benefits from this unbalanced store of carbon as it reduces accumulations of carbon in our atmosphere, effectively curbing or steadying the rate of global warming.
What does this study reveal?
According to ScienceDaily, “most earth system models predict that this growth stimulation will continue to cause a net carbon uptake of forests this century.” The new Leeds study suggests that carbon uptake rates of forests are likely to decrease in the future. The forests around the world are not just growing faster in organism numbers, individual organisms within these forests are each growing faster than they used to. This accelerated growth in individual trees is now confirmed to result in shorter tree lifespans. Shorter lifespans means less time sequestering the carbon. The study basically posits that the current increases in forest carbon stocks may be short lived.
The take-away?
Right now, as a global community, trees are sequestering more carbon than they are releasing, because they are growing at a faster rate than they are dying. In the future, they may start dying at a faster rate then they are growing, which would result in a net-neutral scenario (best case) or net-release of carbon (worst case). In order to keep the tree carbon cycle at net-neutral or net-uptake, we need to limit deforestation. The deforestation rates aren’t necessarily incorporating this future mortality of all these fast-growing forests. Carbon release is about to compound. We better start thinking of ways to combat this compounding.
3. What a Plant Sees
The language I’m using is anthropomorphizing, but only to bring the plant world closer to our human field of awareness.
How do humans see?
Human sight works like this: Light bounces off an object and those refracted rays of light make contact with the retina, a light-sensitive layer of tissue lining the back of the eye. Special cells called photoreceptors turn the light into electrical signals that travel through the optic nerve and into the brain. The brain interprets these signals and an image is created in your mind. In human sight, there is a light sensing receptor, and transmission and interpretation of that information, and finally a reaction to that information.
How do plants see?
If we understand sight to be the interpretation of and reaction to light rays, then the organ needed to “see” doesn’t necessarily need to be an eye. While Plants may not have eyes and optic nerves, they do have specialized organs that register light and turn that light into information that is sent throughout the plant.
Whereas humans’ eyes are in the front of the head, high on the body, and near the brain, plants’ “eyes” are all over their bodies. Human evolution favored the top & front positioning of our eyes because it gives us a good view, focus, and wide visual field as we move around our environment. Plants evolved a bit differently than humans due to their sessile nature. One of the main evolutionary differences is the dispersed consciousness of plants. “Plant organisms have evolved so as to avoid concentrating their functions in a single area of the body, and thus circumvent the risk that being a snack for an herbivore will end tragically for the plant.”writes Stefano Mancuso in Brilliant Green. A plant’s “eyes” or photoreceptors are found in the highest numbers in the leaves, but these photoreceptors exist in the stem, shoots, roots, and even bark or wood too.
What do plants see?
In phototropism, a plant orientates itself in response to light either toward the source of light (positive phototropism) or away from it (negative phototropism). The tip of the plant contains photoreceptors that perceive light rays. This perception is transduced to other parts of the plant, causing a reaction to the light, either bending towards or away from the source.
Here’s a movie of bean seedlings moving in response to a change in light source. Every 12 hours the light is being moved from one side to the other:
In photoperiodism, plants respond to the seasonal change in day length. This means they not only perceive and react to the source of the light but also to the change in the length of exposure each day over time. This is confirmed by the flowering cadences of certain species. For example, soy beans only flower when they perceive (or “see”) that the days are getting shorter and irises only flower when they perceive that the days are getting longer.
More academic explanation from Khan Academy:
But plants aren’t seeing just light vs dark. They see in color too.
Red, far red, blue, and ultraviolet wavelengths are distinguished by different plant photoreceptors. Mancuso explains that “these are the most important wavelengths for the plant since they regulate many aspects of its development, from germination to growth to flowering.” We know that plants distinguish between red and blue light thanks to different experiments done in the mid 1900 century. These studies are further explained in this video from the great Coursera class called What A Plant Knows:
Plants have many more photoreceptors than humans, and are able to see more of the light spectrum. It is easy to understand why plants have evolved more sensitivity to light than humans when we consider what light to a plant. Light is food. Light rays provide the source of energy that plants require to make sugars. So, because plants are sessile beings, stuck in one place, they’ve developed the ability to detect the direction, the intensity, and the type of light rays they are exposed to and the ability to react to this information in a way that benefits them. Plants can see.
But wait, here’s the craziest part: We now think some plants not only see light and color but shapes too. We think this because a common woody vine growing all over the temperate forests of Chile and Argentina can change the shape, size, and color of its leaves to match whatever leaves are growing nearby. The Boquila trifoliolata is a master in mimicry. This plant can regulate the features of its own leaves with incredible flexibility; one plant has even been documented changing its leaves so that they are confused with two or three different species growing nearby. This means the Boquila is able to detect the various qualities of its neighbor’s form and then modulate the expression of its genes to match what it is perceiving. This is f****** incredible.
The visual capacity of plants has largely been considered too eccentric an idea for the scientific community to get behind. But Stefano Mancuso, in The Revolutionary Genius of Plants, explains that as early as 1905 there were supporters of the idea that plants are able to perceive images due to the cells of their epidermis.”The epidermis of a plant is convex like a lens and could conceivably convey the images of surrounding plants to the underlying cellular layer.” Recent discoveries confirming the visual capacity for unicellular organisms has brought the theories around plant vision back into favor. I, for one, am eagerly awaiting more news on this research.
4. Trees in Art
The Brazilian artist Henrique Oliveira builds trees that explode through gallery walls, stretch up into ceilings, and crack open the museum floors. Like the great roots of any too-contained sidewalk tree, his work reminds me of the true strength and force of nature and the ways in which human constructions always eventual fail to contain it.
5. Botany Basics: Leaves
I recently learned that Elon Musk uses tree imagery to explain his approach to learning.
“One bit of advice: it is important to view knowledge as sort of a semantic tree — make sure you understand the fundamental principles, i.e. the trunk and big branches, before you get into the leaves/details or there is nothing for them to hang on to.” - Elon Musk
He is one of many thought leaders who emphasizes the importance of mastering foundational knowledge. So let’s start with plant morphology (the study of the physical form and external structure of plants); let’s look at a leaf...
