UC professor Santa Barbara, Dr. David Tilman, has spent his life learning that, above all, the biodiversity of the earth is vital. But when he presented the idea for the first time, his ecologist colleagues were not convinced.
Quick advance of 30 years, and Tilman was one of the recipients of the Biden Administration of the National Science Medal of 2025 – The highest scientific honor in America – for its work. “It’s special,” said the 49 -year -old professor. “It is my government who tells me that they appreciate how I spent my life.”
Thanks to his research, Tilman discovered that the number of species in an ecosystem is “the most important factor” for the health of this ecosystem. This idea intrigued her, he said, more than the study of a singular plant or an animal species, like others in his field.
Tilman asked an important question: For what Has the earth become so diverse?
To find an answer, he studied herbs in American meadows to learn more about the effects of competition. When the plants clashed, they have become more specialized as a kind of “compromise”. Specializations allow plants to coexist, even if they compete, he explained.
He compared an ecosystem to an economic system in this way, with many professions fulfilled by people who have perfected their profession. This diversity, he said, makes a system more productive and stable.
He first presented these important results in 1994. However, most environmentalists at the time did not believe that diversity counted. If anything, they thought it made a ecosystem more unstable. If the plumbers suddenly disappeared from Santa Barbara, for example, the consequences would be devastating. Lawyers could not suddenly intervene to fill the void. No law school could teach you to repair a leak. In this way, specializations would not allow an essential overlap to fill potential gaps in the environment, thought environmentalists.
But ecological diversity is not so simple. The diversity of nature leads to “functional overlap”, allowing organisms to take up certain parts of the roles of other species if this species disappears, said Tilman. (Without a doubt, some lawyers know how to repair a pipe.)
In his studies of meadows, for example, Tilman noted that the plots with more species were more resilient to drought than those who had less.
A loss of diversity, on the other hand, leads to ecosystems less capable of providing the company with goods and services – such as drinking water, air and housing. At present, we are in the midst of a historical loss of this precious diversity, with humanity as a driver. Companies such as agriculture and the combustion of fossil fuels have led to the degradation of housing and the sixth mass extinction of the earth, known as Anthropocene.
Tilman, in response, has turned his attention to the way in which human impacts on nature come back to affect us and how biodiversity can be part of the solution. His work includes Research on the diversification of cultures, and healthy and lasting changes to the modern regimeAccording to UCSB The current.
After coming to Santa Barbara as a guest teacher, Tilman was attracted to the UCSB Bren School of Environmental Science and Management. “Unlike a traditional ecology program,” he said, “the Bren school is dedicated to resolving major environmental problems, focusing on long-term problems for humanity.”
Tilman now teaches the UCSB every quarter of winter. Otherwise, he worked in his role as professor of regents at the College of Biological Sciences at the University of Minnesota.
“When I look at my students, to tackle these big problems, I say to myself:” WOW, what a big group of researchers “, he smiles.
While reflecting on the teaching of the next generation of ecologists, he said that he had never imagined that there would be a “rapid” societal response to environmental problems.
Our total impact is now 100 times worse than 100 years ago, he said. The rules and regulations have not followed this pace of this impact.
“Each nation must be involved in the climate solution, as each nation must be involved in the prevention of extinction,” he said. “If we continue to do what we do, what kind of people do we create?” We are the dominant force on earth – we have to ask ourselves these questions. »»
However, Tilman said he was optimistic about the future. It is “discouraged that we cause problems that do not need to be here”, but we will have to “turn the turn” and possibly approach our actions. “I hope earlier than late, because it will save a lot of difficulties and pain,” he continued, giving the example of recent Los Angeles fires. “And personally, I don’t think these problems have something to do with a political party. It has to do with logic. »»
Tilman, 76, said that he was going to continue looking for solutions that can be achieved to these problems. He always does research and writing articles. He has “health and enthusiasm” to continue.
“Right now, I can’t imagine why I would retire. I haven’t saved the world yet, ”he gleams.