Life is found across the planet, including in some pretty inhospitable places. Plants and animals have adapted and thrive everywhere from icy Antarctica to the Sonoran desert; from deep-sea hydrothermal vents to freshwater lakes and temperate woodlands.
Some regions, known as biodiversity hotspots, support incredible numbers and varieties of living things. Tropical rain forests and coral reefs are among the most productive and diverse places for life on Earth, and yet face unprecedented threats to their survival.
But what factors make some places species-rich? What ecological influences are most critical to sustaining varied and abundant life? And how will the accelerating impacts of human-driven climate change affect species and the places that support them?
Scientists now have an answer — one that will help inform efforts to preserve biodiversity and protect critical habitats as climate change continues to disrupt ecosystems across the planet.
A unified map reveals Earth’s richness
Researchers from the Monterey Bay Aquarium, together with colleagues from the University of British Columbia, the National Oceanic and Atmospheric Administration (NOAA) and other institutions, have created the first unified global biodiversity map covering species both on land and in the ocean.
Their work documents more than 67,000 marine and terrestrial species to determine where the most species occur worldwide and to identify the environmental drivers that influence whether life will thrive or struggle.
By combining observational data with a new machine-learning approach that uses artificial neural networks, they’ve mapped and forecasted where species should occur based on primary food production from plants, temperature, elevation (on land), depth (in the ocean), precipitation (on land), and dissolved oxygen (in the ocean), among other factors.
The research documents which of these “environmental drivers” matters most for living species. This can inform resource managers as they work to protect critical habitats and species in a time of accelerating global change.
“Maps show us where we are,” said Dr. Kyle Van Houtan, chief scientist at Monterey Bay Aquarium and senior author for the paper published February 5 in PLOS ONE. “This study also shows us where we are going.”
Where land meets ocean
The ocean, global biodiversity and human society are all deeply interconnected. The ocean serves as the heart of our planet’s climate system, providing benefits like food, predictable weather patterns and a steady global average temperature. But some human activity, such as burning fossil fuels for energy, disrupts global biodiversity — not only driving climate change, but also impeding the ocean’s ability to buffer it.
Through this study, scientists have developed a better and more accurate understanding of biodiversity: the land and ocean areas that wildlife currently inhabit, where these species might end up moving, and how we can best protect them in a changing world.
Determining where species are most abundant, along with charting the patterns of their movements, represents one of the pillars of ecology. But for a long time, such studies have focused mostly on the terrestrial realm due to the greater accessibility and lower cost of sampling on land.
“We are terrestrial creatures, and so we have a natural bias favoring the land,” said Dr. Clinton Jenkins, a professor at the IPÊ – Institute for Ecological Research in São Paulo, Brazil. “However, much of the world’s diversity is aquatic, living in the 70 percent of the Earth’s surface that is ocean, lakes and rivers.”
In other words, this team of scientists sought to better understand the biosphere as a whole, not just the parts with which we are already most familiar, Clinton said.
“By gathering information on both the ocean and terrestrial realm, we were able to integrate the work of two scientific communities that have the same objectives, to provide a unified picture of life on Earth that has sustained humanity for centuries,” said Dr. Gabriel Reygondeau, co-author of the paper and a research associate at the University of British Columbia and Yale University.
“Studying the global patterns of diversity without regard to realm allows us to reevaluate our theoretical knowledge in the discipline,” he explained. “This will provide more efficient tools in the context of a biodiversity crisis, which is truly global.”
Charting a course for the future
The research will have practical applications for resource managers, said co-author Dr. Elliott Hazen, a research ecologist with NOAA’s Southwest Fisheries Science Center.
“This helps us document where climate change mechanisms may influence animals most and identify environmental conditions that have more or less biodiversity than we might expect,” he said.
“We need to understand the drivers of biodiversity to preserve species within ecosystems that are moving due to changing environmental conditions, and to allow us to take a more dynamic approach toward protecting them.”
Tyler Gagné, a data scientist and lead analyst of the study, developed the data analytics framework that underpins the global mapping while working at Monterey Bay Aquarium.
The data highlight places that are species-rich and species poor, as well as regions on land and in the ocean that support more, or fewer, species than the topography and environmental conditions predict.
“Current patterns of species richness are the result of ecological and evolutionary processes that unfolded over geological time scales — millions of years,” Kyle said. “We are now witnessing global change at a pace we have not experienced.”
The fixed limits of national parks and marine protected areas may be questioned as conditions change and species move in search of more favorable locations, he said.
“Protected areas on land and in the ocean were created to protect ecological communities in stable environments, but what do we do if protected species move beyond these boundaries?” Kyle asked.
Luckily, this science supports solutions.
“Our research has pinpointed the environmental factors that allow such an abundance of life to flourish on Earth and enables a flexible, data-driven approach to protect the biodiversity of our one wild and precious planet.”
— Ken Peterson