Researchers have long been looking at how climate change influences animal behavior: polar bears hunting reindeer instead of seals; parrots with larger beaks to better regulate their body temperature in the face of increased heat; or marine species that move towards the poles. A new large-scale study by a hundred researchers suggests that primates are also being affected.
Monkeys from America and lemurs from Madagascar, species that are exclusively or fundamentally arboreal, abandon the trees to descend to the ground due to warming and deforestation. Spending more time on the ground represents a drastic change in their way of life, exposing themselves to the lack of food and shelter, and to large predators. Ultimately, either they adapt or they may suffer an impact that is difficult to calculate.
The research, published in the Proceedings of the National Academy of Sciences (PNAS), has tracked 32 species of monkeys -including spider, howler, marmoset and capuchin monkeys- and 15 lemurs -bamboo lemurs, crowned , ring-tailed, sifakas- during more than 150,000 hours of observation at 68 sites in the Americas and Madagascar. Groups of animals from one corner of the planet to another showed the same tendency to adopt a terrestrial lifestyle for a longer time.
“A catastrophic impact”
«It is a wonderful study, a delight -appreciates Michael Llorente, professor of the Serra Húnter program at the University of Girona and who has not participated in it-; it has what the science of the future should have: international collaboration to try to solve big questions and to be able to appreciate changes on a planetary scale».
Although the species examined spent an average of only 2.5% of their time each month on the ground, the analysis identified variations both between and within species. As Llorente, also director of the master’s degree in Primatology, explains to this newspaper, these species have evolved over thousands or millions of years to live in trees and have developed successful strategies to feed and protect themselves from predators. Now, “due to human responsibility, they are forced to leave this lifestyle in a 180º turn that can have a catastrophic impact,” he laments.
Verreaux’s sifaca, from Madagascar
The transition from an arboreal to a terrestrial lifestyle has occurred before in the evolution of primates, including hominids, but the current changes are so rapid that they are, according to the authors, “a serious threat”. The consequences are difficult to foresee.
“We don’t know what can happen. I don’t think they have time to adapt,” says Llorente, who believes that the main problem for these animals will be finding food. The researchers explain in the study that primates that eat a more generalized diet (not just fruit) and live in larger groups can adapt more easily. However, species adapted to a certain type of fruit or leaf will be forced to change their diet and may not find enough or appropriate food to survive. Also, on the ground they face higher risks of predation, such as large carnivores or snakes. Those who live near highways or human settlements also suffer more problems.
It will influence your evolution.
“These primates are mostly very intelligent and I am hopeful that they may be able to adapt,” says the Spanish researcher. Those that do not will require quick and effective conservation strategies to ensure their survival. In any case, he has “no doubt” that the change will affect the evolution of these animals. “But we are not going to see it because it is a very slow process, thousands or tens of thousands of years,” he points out.
For Llorente, the next step is to repeat the study in Africa and Asia, and see how deforestation affects species such as gorillas or baboons, which are mainly terrestrial but, for example, carry out some key activities in the trees, such as sleeping. .
“The study shows something that everyone intuited but that no one had been able to quantify on a planetary scale and shows how this climate crisis affects everything,” he adds.