Stephen Hubbell, a distinguished professor of ecology and evolutionary biology at UCLA, is the 2016 laureate of the International Prize for Biology for his outstanding contributions to biology research, Japan’s Society for the Promotion of Science announced Friday. The International Prize for Biology as one of the highest scientific honors bestowed by Japan.

Hubbell, a faculty member in the UCLA Life Sciences Division of the UCLA College, is renowned as an international leader in advancing our scientific understanding of complex tropical forests, essential data for their successful conservation and management. He has published four books — including “The Unified Neutral Theory of Biodiversity and Biogeography,” which has been cited more than 5,800 times — and authored more than 220 scientific papers on tropical plant ecology, theoretical ecology, plant-animal interactions and animal behavior.

His unified neutral theory of biodiversity and biogeography is a mathematical theory that offers a nontraditional explanation for the diversity and relative abundance of species in ecological communities. The traditional explanation invokes niche differences to explain the coexistence of species in ecological communities. Hubbell’s theory has engendered a sustained global debate about the mechanisms of assembly of species into ecological communities, and it has raised questions about the stability of such assemblages.

Hubbell and his colleagues have been testing his theory and alternative theories to explain the high tree species diversity in tropical rain forests in a global network of large-scale permanent forest plots, all following the research protocols designed by Hubbell when he established the first of these plots in 1980 on Barro Colorado Island, Panama.

Hubbell is co-founder of the Center for Tropical Forest Science at the Smithsonian Institution, which manages this plot network, a network that now spans 25 countries and collectively contains more than 6 million living specimens of more than 10,000 tree species — about one-fifth of all tree species in the world. Standardized data on forests available from the plot network enable scientists to determine which features of tropical forests are universal and true of all forests, and which are specific to particular forests. The data also enable scientists to evaluate how global climate charge is affecting forest health and biodiversity around the world.

Hubbell is the recipient of many awards and honors for his research, including a Scientific Achievement Award by the International Union of Forest Research Organizations in 2014, an award no American had won in more than 40 years, as well as a Lifetime Achievement Award from the British Ecological Society in 2013. He is a fellow of the American Academy of Arts and Sciences and of the American Association for the Advance­ment of Science, and he received a Guggenheim fellowship in 1983. He joined the UCLA faculty in 2007.

He is also founding chairman of the National Council for Science and the Environment (NCSE), a nongovernmental organization in Washington, D.C., whose mission is to improve the scientific basis of environmental decision-making. NCSE addresses many environmental science policy issues, including biodiversity, conservation and the extinction crisis.

“We need much better data on the distribution of life on Earth,” Hubbell said in a 2011 interview. “We need to rapidly increase our understanding of where species are on the planet. We need citizens to record their local biodiversity. There are not enough scientists to gather the information. We also need much deeper thought about how we can estimate the extinction rate properly to improve the science behind conservation planning. If you don't know what you have, it is hard to conserve it.”

Hubbell has long encouraged the public to spend more time enjoying nature. “If we don’t take steps to preserve animals and plants that we care about, they are going to be gone.

“When I was a kid, I spent a lot of time doing non-macho things like collecting butterflies and turning over rocks,” he said. “The only way we’re going to save nature is by making sure future generations experience nature. People who have never seen wild nature don’t miss it and don’t realize how impoverished their lives have become due to its loss. I worry about the loss of a conservation ethic among the public. Go to the tropics. Experience a rain forest — while you still can.”