Rare species group together to survive in nature 

Corals are among the species studied, where rare types group together to survive. Keystone

Rare plant and animal species cluster together to help each other, which in turn helps maintain biodiversity, according to new Swiss and Swedish research. 

The study by scientists at the University of Geneva (UNIGE) and Umeå University in Sweden “demonstrates that animal and plant communities are organized into ethnic neighbourhoods, where species in low abundance come together to strengthen their persistence against more competitive species”, according to a UNIGE statement.External link  

Scientists analysed more than 300 communities of mosses, plants, insects and corals in various regions of the world. By combining network theory and numerical simulations, they detected “ghettos” and explored the mechanisms behind their functioning. 

And the results, published in the journal Nature Ecology & EvolutionExternal link, show that the spatial clustering of rare species helps their survival.  

One example is the coral reefs of Tykus island in Indonesia.  

“On this island, Montipora digitata, a species of cnidaria, is the most dominant and abundant species on the coral reef,” explains Jaime Madrigal-Gonzalez, a researcher at UNIGE. “It is accompanied by rare species, such as the branched fire coral or the coral-mushroom shield. To avoid being eliminated by the dominant species, these rare corals form small associations and tend to grow one beside the other.” 

According to Darwin’s theory of evolution, rare species should be excluded by more efficient species in highly competitive environments, but it is known that ecological communities are formed by many rare species. This study thus offers a “first explanation capable of solving this major Gordian knot of current ecological sciences”, says UNIGE.