Although often overlooked, rare species play a more unique role in ecosystems than previously assumed.

In a paper published last month, researchers proposed a guideline for better understanding how rare species benefit the ecosystems on which people depend. The research, conducted by University of Minnesota researchers and others, could also help inform global policy initiatives responding to the world’s acute biodiversity crisis, according to researchers on the study.

Most studies do not focus on rare species and, in many cases, rare species are assumed to contribute little to ecosystems, according to the paper. 

“I think identifying ways rare species can make contributions to people could be a key link between protecting biodiversity and also promoting human well-being,” said Laura Dee, lead author and assistant professor of conservation science at the University.

Rare species contribute to their ecosystems and support human life in a variety of unique and often unconventional ways, according to the research. 

“We point out the ways that local populations in one area might contribute to ecosystem services globally,” said Stephanie Pau, co-author and assistant professor at Florida State University.

For example, the giant sequoia, a tree species that lives in Northern California, has a limited geographic range. It only occurs in one place and is not widespread, she said.

“But the role it plays in carbon storage is a global benefit, and so that’s one way of thinking about how land managers, policymakers in there, in California, can help manage that population, but the effects of it are global,” Pau said.

While their impact is wide-reaching, the paper claims that the number of rare species may be declining with changes in global land use and climate. Understanding their unique traits and how they contribute to ecosystem services may change as a result, Pau said.

In a recent report, the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services showed deep concern about the effects this decline may have on people.

“I think it also identifies opportunities for cost-effective conservation, that potentially the information could be used by nonprofit or governmental organizations that are interested in achieving multiple objectives for conservation,” Dee said.

In the report, researchers pointed out that both biodiversity and ecosystem services do not always align with each other. But considering rare species helps think about consistent strategies that protect both biodiversity and ecosystem services, they said.

“This research delineates all the ways that rare species may be important for us now and in the future, and is an important tool or consideration for how to find areas of alignment for current conservation goals,” Jane Cowles, a co-author and postdoctoral associate at the University, said in an email.

The next step of the research is trying to understand the unique functional role of rare species, and how that might change with global change.

“We’re sort of providing this framework for thinking about the problem,” Pau said.