Study shows seed dispersers help plants 'climb' mountains and escape climate change

A study led by Sara Mendes and Rúben Heleno, researchers at the Centre for Functional Ecology (CFE) of the Faculty of Sciences and Technology of the University of Coimbra (FCTUC), has concluded that seed dispersers help plants ascend mountains to escape climate change.

This research, published in the journal New Phytologist, identified all the animal species (seed dispersers) responsible for spreading each plant species across the five altitudinal vegetation levels of Tenerife, in the Canary Islands. Tenerife, the highest point in the Atlantic Ocean at 3,718 metres above sea level, has vertically structured vegetation, making it an ideal location to study how species respond to climate change in mountainous ecosystems.

“We spent two years climbing up and down the mountain, resulting in one of the most comprehensive seed dispersal networks ever assembled in the world. Our findings reveal that seed dispersers connect different layers of vegetation by ingesting fruits and dispersing viable seeds along ‘corridors’ that stretch from the shore to the mountain's summit. This enables the next generation of plants to sprout and thrive at higher altitudes, escaping the harsh effects of climate change at lower elevations, such as drought and heat,” explains Sara Mendes, lead author of the study.

According to the authors, one of the most important and unexpected findings was the discovery of seeds from eleven plant species dispersed by animals (in their droppings) to altitudes higher than where the adult plants currently exist. "These seeds show that animals can help plants move uphill fast enough to keep up with climate change".

However, the experts warn: "The study also revealed a worrying finding: more than half of the plants that animals help are invasive species that could take advantage of this uplift, posing a potential threat to native ecosystems. The research highlights the importance of protecting seed-dispersing animals, both for their intrinsic value and for the survival of mountain plants in a changing climate, and the urgent need to control the spread of invasive species.

The scientific article “Climb forest, climb: Diverse disperser communities are key to assist plants tracking climate change on altitudinal gradients” is available here.