Ecologists involved in mapping all life on Earth have now taken the next step: predicting where the life we don’t know about is waiting to be discovered. As a first pass, they have created an interactive map showing diversity hot spots with the richest potential for new mammal, bird, reptile, and amphibian species. They describe their results today in Nature Ecology & Evolution.
“Unknown species are usually left out of conservation planning, management, and decision-making,” says co-author Mario Moura, an ecologist at the Federal University of Paraíba. “If we want to improve biodiversity conservation worldwide, we need to better know its species.”
It never sat well with Moura that an estimated 85% of Earth’s species are still undescribed. So, in 2018, this newly minted Ph.D. in ecology teamed up with ecologist Walter Jetz at Yale University to come up with a way to better predict where those unknowns are. “The chances of being discovered and described early are not equal among species,” Moura explains. For example, large mammals living near people are much more likely to have been documented by scientists than tiny frogs living in a remote jungle.
Over 2 years, Moura and Jetz compiled data on size, habitat, and nine other attributes—including how many taxonomists study them—for all of the known 32,000 vertebrates. Using a computer model, they determined the probability of when an organism with different combinations of these attributes would have been—or will be—discovered and where. “Our approach uses known species to predict unknown ones,” Moura says.
They predict that some places, such as the Guinean forests of West Africa and many Southeast Asian islands, are likely to be rich in undescribed organisms because they have high densities of species but are relatively inaccessible. More than 10% of the world’s undiscovered land vertebrates are in Brazil; Madagascar, Colombia, and Indonesia account for 5% each, Moura and Jetz conclude. Overall, such discovery hot spots account for just 10% of the Earth’s land surface but hold almost 70% of the projected future discoveries of new species, they note.
Many of those discoveries will be in tropical forests and will uncover lots of frogs, geckos, and other amphibians and reptiles, which represent three-quarters of what’s still unknown, the researchers report. Among mammals, they expect more rodents, bats, and primates to be uncovered; among birds, perhaps just a few songbirds.
Their new map of “species discovery potential” can help guide conservation planning, Jetz says. “I see tremendous opportunity for the findings to help more efficiently deploy the limited resources and time for discovery work.” Researchers could use the maps, for instance, to target areas expected to be hit hard by climate change, in order to better understand the impacts.
In the meantime, the mapmakers say they are not done. Next, they hope to develop similar maps that could help scientists find and describe thousands of species of invertebrates and plants.