Co-extinction increases estimates of species disappearance
(sustainabilityenvironment.com) – By the end of the century, 27% of animal species will disappear from the planet. Regardless of our actions today and in the future. Including compliance with the new 2030 nature protection targets endorsed today by COP15 on biodiversity. It is the extinction ’embedded’ in the level of climate crisis and change in the use of soils today, which will be triggered by a domino effect now set in motion. But by 2050, the disappearance of species will affect 1 in 10 animals.
Confirmation that the 6 th mass extinction is ongoing comes from a study by the EU JRC and the University of Flinders. The study, published in Science Advances, evaluated the trend of primary extinctions and co-extinctions up to 2100 from a simulated model that includes the impact of climate and soil on 15 thousand food chains intertwined. All are processed by one of the most powerful supercomputers available in Europe.
Thanks to the simulation it is possible to keep track not only of the ‘direct’ extinction of animals, due to loss of habitat, but also of the ‘secondary’ extinctions, that is to say the disappearance of the species that depend on the former and see their food chain disturbed. “Think of a predatory species that loses its prey due to climate change. The loss of the predated species is a ‘primary extinction’, because it has succumbed directly to a disturbance. But having nothing to eat, even its predator will become extinct (a “co-extinction”). Or, imagine that a parasite loses its host due to deforestation, or that a flowering plant loses its pollinators due to too hot. Each species depends in some way on the others,” explains Corey Bradshaw, co-author of the article.
In this way it is possible to obtain a more precise estimate of the size of the disappearance of the species. The simulation, conducted on three different climate scenarios of the IPCC, shows that secondary extinctions are 34% more than what would be estimated if only direct effects were considered. A significant figure then concerns the most endangered species: using this model, their disappearance by the end of the century increases by 184%.