(CN) — Humans have had a long and often fraught history in changing the planet and the environments we inhabit. Now, new research shows that we’re not just changing the world around us — we’re also changing the natural process of evolution as we know it.
Not unlike virtually every living thing on the planet, humans are a product of millions of years of evolution. This process allowed us to grow from a collection of single-celled organisms to the most influential species on Earth and has been propelling our progression through nature ever since.
But as much as we have been shaped by evolution, questions linger on how that relationship might work going in the other direction. How the process of evolution, despite predating humankind by countless years, has changed with the growing rise of human influence over nature. Now, groundbreaking research reveals just how far that change has gone.
In a study published Thursday in the journal Science, nearly 300 scientists spanning across dozens of counties and 160 different cities reveal they’ve collected the most definitive evidence to date that humans — and specifically the larger cities we’ve constructed — have become the newest dominating force behind evolution. And they proved it by looking at one of the most common plants on Earth.
“We’ve long known that we’ve changed cities in pretty profound ways and we’ve dramatically altered the environment and ecosystems,” James Santangelo, UTM biology PhD student and study co-lead, said with the release of the study. “But we just showed this happens, often in similar ways, on a global scale.”
The study details how the Global Urban Evolution Project (GLUE) analyzed data from common white clovers found in cities all across the world. After collecting data from nearly 200 cities, they found that white clovers have been adapting and evolving directly to these urban sprawls in ways completely different to how they would be evolving in more rural spots.
Because larger cities tend to be more similar to each other than they are different, experts found that city-based white clovers will be far more similar to each other than their rural counterparts — even if those cities are on the other side of the globe. For example, a white clover in Tokyo, Japan will have much more in common with a white clover in Toronto, Canada than it would with a white clover in a nearby forest.
Experts were even able to hone-in on how this was taking place. White clover produces hydrogen cyanide to help ward off hungry herbivores and to increase its water stress tolerance, and experts found that clovers in the city were producing far less of this when compared to their rural siblings.
This evolution didn’t even discriminate based on geography. Despite a massive dataset that encompassed an environmentally diverse collection of cities, experts discovered their findings held up across cities of all temperatures and climates.
Experts warn not to be fooled by the modesty of the simple clover. While the white clover was chosen for this project because of its abundance across nearly every major city on Earth, Thursday’s findings could change the fundamental way we look at evolution in nature at large.
“This study is a model to understand how humans change the evolution of life around us,” said Rob Ness, an assistant professor of biology at UTM who co-led the project. “Cities are where people live, and this is the most compelling evidence we have that we are altering the evolution of life in them. Beyond ecologists and evolutionary biologists, this is going to be important for society.”
Of course, Thursday’s reveal is only the beginning. On top of being what could be a new standard for inclusivity in science — the team that worked on the project was equally split between women and men and included both official researchers and students of all stations — it sequenced more than 2,500 clover genomes, providing future experts with data that can be studied for years.
It will also help outfit conservationists with new strategies to help protect rare or endangered species, particularly as we try to help them adjust to more urban locales. And through these efforts, researchers are hopeful we can learn even more on how human hands have come to influence the very same evolutionary process that brought us all here in the first place.
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