Environmental (Commonwealth Union)_ From rainforests to coral reefs, from mountains to deserts, life on our planet can appear to be splashed haphazardly across its great and varied landscapes. Yet a groundbreaking paper in Nature Ecology & Evolution discloses a shocking fact: global diversity is governed by a unified spatial principle, determining where species, trees, and turtles alike disperse.
Based on data from over 30,000 species across seven major groups of biology, including amphibians, dragonflies, birds, mammals, reptiles, rays, and trees, scientists at Sweden’s Umeå University, Spain’s Rey Juan Carlos University, and several UK organizations uncovered a pattern that appears to hold true throughout ecosystems and continents.
In every bioregion, there is always a core where the majority of the species are found,” explains Rubén Bernardo-Madrid, lead author of the paper. “Species radiate outward from the core to adjacent areas, but only some persist.”
A Core Rule of Life
The research found that each type of habitat—forest, ocean, savanna, or wetland—possesses a central “core” area where biodiversity is greatest. It is present as the center, enjoying optimal conditions for species to thrive, evolve, and diversify.
As species migrate away from these hubs into transition areas, only a fraction can endure the altered conditions of the environment. These zone areas, marked by more severe climates, changed soils, or competition from other species, sort out all but the most resilient forms of life.
This pattern wasn’t the exception. It did this again and again across continents, climates, and forms of species, demonstrating that life isn’t randomly scattered; it’s reading a more primary ecological script.
The Science Behind the Structure
To search for this covert pattern, scientists analyzed four major components of biodiversity:
- Species richness: The variety of species present within an area
- Range size: How far and wide those species are dispersed
- Endemicity: Whether or not the species are endemic to the area
- Biota overlap: To what extent they overlap with adjacent areas
Using this knowledge, researchers categorized each area into seven types of regions, ranging from species-rich centers to edge zones of biodiversity where species from multiple regions intermingle. The result? The system is nested, extending from the center to the periphery, resembling a set of concentric rings encircling a central point.
The underlying principle of this spatial thinking is a process known as environmental filtering, the idea that only those species well-suited to the conditions can survive there.
“These environmental filters are like invisible gates,” says co-author Joaquín Calatayud. “In the center, conditions are ideal, so many species can succeed. At the periphery, only a few species pass the test.”
Implications for a Changing World
While the study is a fascinating look at the way life organizes itself, the real strength lies in what it can tell us about conservation. If biodiversity is condensed into small core areas, then preserving these is of utmost importance.
“These core areas are like biodiversity engines,” Bernardo-Madrid explains. “If we lose them, we risk shutting down the system.”
As climate change, pollution, and habitat destruction continue to spread, knowing where life clusters can help us better predict how ecosystems will shift. If a core area becomes uninhabitable, entire species networks could collapse.
Moreover, the findings of the study oppose the premise that biodiversity is all a matter of coincidence. Rather, it suggests that life consistently responds to its environment—a finding that can serve to guide future endeavors in reforestation, habitat restoration, and species relocation.
One Earth, One Pattern
One of the surprises of this discovery is how universal it is. From tropical dragonflies to Nordic forests, from African snakes to deep-sea rays, the researchers discovered the same center-outward pattern.
The discovery suggests that Earth’s diversity is following a global playbook, a script written not in one language of genes or species but in the collective wisdom of ecological adaptation.
In an era in which nature frequently seems to be under attack, this finding brings hope. If we can figure out the organization of life, we can learn how to sustain, restore, and defend it as well.
As the world marks World Environment Day by calling to save nature’s balance, this research is a poignant reminder: Life isn’t cast about with no pattern; it’s shaped by patterns. And having those patterns in one’s hands is the secret to keeping Earth alive.
