Defaunation threatens plant diversity

Abstract

Half of all plants rely on animals to disperse their seeds. This biotic dispersal allows plants to maintain gene flow between fragmented populations, recover from perturbation and expand their distribution ranges — responses that underlie the capacity of plants to track new habitats with climate change. Therefore, declining animal populations, which are both a consequence and a driver of global change, pose a substantial threat to plant diversity.

In a recent study published in Science, Ruben Heleno and colleagues constructed a European-wide plant–animal seed dispersal network and assessed the conservation status of these interactions. Their literature search of over 50,000 publications yielded a network of 5,030 interactions between 592 native plants adapted to seed dispersal and 398 disperser species. A third of these disperser species, and therefore their interactions with plants, were categorized as high or very high concern by IUCN (International Union for Conservation of Nature), pointing to a developing seed dispersal crisis across Europe.