Plant Science

The Ecosystem of Humanity


In 2017, I was a fledgling PhD student, just finding my feet. Towards the end of the year, I was invited back to my secondary school as guest speaker, for the fifth anniversary of their diversity and inclusivity event. It was an incredible honour to even be considered, but also completely terrifying. “A professional plant scientist”: the title held up to me that I felt totally undeserving of. I had all of the same love and passion for plant science as I do now, but didn’t feel I had the credentials to be considered a professional in the field. Over the last three years, I’ve come to realise that it isn’t the credentials or years in service that determine your title, it’s your passion, determination and commitment to that field.

Looking back at my speech brings me overwhelming nostalgia; to a Bethany who lacked confidence but held those three principle characteristics. This speech is a milestone in my career as a plant scientist, and I’d love to share it with you today. In it, I describe the importance of biodiversity in ecology and how this importance is translated into diversity within the human race. One aspect that I highlight seems particular apt for 2020, which is why I’m revisiting this now: diversity in the face of natural disasters. Diversity is important in the face of  change, and nature has shown, time and time again, that by working together, communities bounce back stronger than ever.

Old Man's Beard Lichen
Old Man’s Beard Lichen in a forest in New Zealand

When Mrs Elliot-Brown invited me back for the 5-year anniversary of STAGS in Colours, my answer was a resounding yes. I remember when she first spoke to me about the idea for this event 5 years ago. I thought, “what a wonderful way to celebrate not only the immense talent at this school, but also the cultural, religious, and individual diversity that walks these halls each day.” Then, when she invited me to be guest speaker, I was truly flattered. I am in the first year of what I hope will be a lifelong career in plant science and ecology. As of yet I don’t feel that I have the knowledge or experience to present at such an event, but I will do my best.

When I was at school, the image painted of ecologists was odd looking scientists, standing in fields throwing wooden squares or swishing nets through long grass. That is far from what I do. Currently, I spend my time at a desk analysing data and producing fancy looking graphs. However, this does have importance. As an ecologist, I am interested in the ecosystem and understanding ecosystem relationships. This can mean either relationships between living things (what we call organisms), or relationships between organisms and their environment. For me, I look at the relationship between plants and their environment. The question is, why?

Ivy-Leaved Toadflax
Ivy-Leaved Toadflax on a sea wall in Cornwall

Climate change is happening. It has been since the birth of our planet. Right now, global temperatures are fluctuating fairly erratically and that’s an issue if you are a plant, or anything really. But it’s especially bad if you rely on certain temperatures to grow and reproduce. The plant I’m currently studying (stonecress) lives on mountain slopes and has a lifespan of a year. Within that year, it only emerges for a few months. If the conditions aren’t right when it grows, that year’s population will fail and it will be up to the following year’s population to make up for the loss.

What I’m doing at the moment is trying to gauge how increasing numbers of bad years will affect the species. This will give me an idea of how well stonecress will survive in more extreme environmental conditions, should climate change get worse. This work focuses on only one species. So, how adaptable is the research for looking at other species? That remains to be seen. Because there is so much diversity in the environment, it is difficult to apply research completed on one species to another. One size does not fit all.

Graphs demonstrating the life of stonecress (Aethionema arabicum)
The life of stonecress (Aethionema arabicum)

This leads me onto one of the most important aspects of ecology: biodiversity. Researchers have estimated that there are between 3 and 30 million species on Earth. Obviously, there is some fine-tuning to do before we have a definitive answer. The biggest problem we face with getting that answer is the ocean. 70% of the Earth’s surface is covered in water and we have explored less than 5% of that. The ocean supports all living organisms and we barely understand it. A lot of money and research is being used to put humans on the surface of Mars, and yet we have not fully explored our own planet. I’ll leave you to ponder that. Biodiversity also boosts an ecosystem’s productivity, meaning how many useful resources it produces – such as clean air, fresh water, food, medicine, building materials and so on.

Biodiversity can be investigated at the largest scale (the entire planet), or on a very small scale (a particular habitat). Let’s, for example, take a look at Verulamium park. If we wanted to look at the biodiversity of Verulamium, we might start with the lawn. What is the most densely populated species of a lawn? Grass might be your answer, and you would almost be right. In a single lawn, there can actually be anywhere up to, and sometimes over, 100 different species of grass alone. Looking at a lawn you’d think it was all the same thing. In reality, it’s actually a very intricate web of many species, interacting with one another and their environment. Each with its own function and purpose. Could the lawn survive without one of those species? Maybe. Maybe not. Is it worth risking the health of the lawn to find out?

Yellowstone National Park

Biodiversity also allows an ecosystem to recover from natural disaster. A good example of this is Yellowstone National Park, in Wyoming USA. On August 20th 1988, a huge fire swept across the park, devouring everything across almost 1 million acres. From the ashes, it was difficult to see if anything would emerge. But where patches of forest once blocked out sunlight, it was now open and light. Small plants thrived where they were once shaded by the tall trees. And where plants thrive, insects are quick to follow. Beautiful, diverse meadows of wildflowers now grow in the place of the forest, revitalising it. If it were not for the incredible diversity in species of that region, perhaps nothing would have grown. Not without time or human assistance. Dr Seth Reice, a professor of Ecology, wrote a book called The Silver Lining in 2001, discussing the benefits of natural disasters. I will quote him here: “The nature of nature is change. And change cannot take place without diversity.”

Where am I going with all this? If within our definition of biodiversity, we replace the word ecosystem with community it is easy to understand why having diversity between people is beneficial to the survival of our species. Every species has its function, its niche, its place on Earth, no one more important than another. Every person has their place in our community, each just as unique, and as important as each other. And it is the diversity with our community that makes us resourceful, strong, connected and beautiful. Tonight, we are celebrating a few cultures, religions and languages within the ecosystem of humanity, and I am thankful to be a part of it.

I want to leave you with these words, from the Finnish metal band Nightwish:

“Follow the aeon path
Greet a blade of grass
Every endless form most beautiful
Alive, aware, in awe
Before the grandeur of it all
Our floating pale blue ark
Of endless forms most beautiful”


Image credits

Aethionema arabicum: Arshad, W., Sperber, K., Steinbrecher, T., Nichols, B., Jansen, V.A., Leubner‐Metzger, G. and Mummenhoff, K., 2019. Dispersal biophysics and adaptive significance of dimorphic diaspores in the annual Aethionema arabicum (Brassicaceae). The New phytologist221(3), p.1434. DOI: 10.1111/nph.15490.

Yellowstone National Park: Acroterionderivative work: Gaendalf / CC BY-SA.


2 thoughts on “The Ecosystem of Humanity”

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s