The lost of biodiversity from birds and mammals caused a 60% decrease in the spread of seeds on a global scale and prevents plants from adapting to climate change, according to a study published in the journal Science.
The research, focused on fleshy-fruited plant species and the frugivorous animals that spread them, demonstrated the direct impact that plant species suffer from not spreading their seeds far enough.
“Extinction and habitat loss damage complex ecological networks. This study shows that animal declines can disrupt ecological networks in ways that compromise the climate resilience of entire ecosystems on which people depend,” said Evan Fricke, first author of the work and researcher at Rice University in the United States.
Because many plant species depend on animals for reproduction, seeds often do not spread far enough, making it difficult to adapt to the environment. climate change, they explained from the Information and Scientific News Service (SINC) of Spain.
“To maintain suitable environmental conditions in a changing climate, many plant species need to ‘migrate’, shifting their geographic range to overcome the climate change“, explained Fricke to SINC.
Scientists believe that if these plant species cannot cope with changes in temperature, the biodiversity of plants and the ecosystem services they provide.
To conduct the study, Fricke and colleagues pooled data from more than 400 seed dispersal networks around the world and developed learning models to predict changes, based “on the species of birds and mammals present in each place”.
They then compared maps showing what dispersal would be like without human-caused extinctions, and the results revealed that the current seed dispersal function declined dramatically from its natural level, with decline especially widespread outside of the tropics
“Temperate regions show some of the largest declines in seed dispersal function,” explained the scientist.
Research shows the correlation between the crisis of biodiversity and the climate crisis, and in the face of this the scientists proposed “improving the connectivity of habitats” to allow free roaming of seed dispersers.
In addition, the work highlighted the need to restore fauna to ensure effective seed dissemination, especially with large animals.
“Large mammals and birds they are especially important as long-distance seed dispersers, but have been largely lost from natural ecosystems,” concluded Christian Svenning, lead author of the study.