New research suggests that animals can thrive in human-dominated environments by being expert judges of risk. Alexis Breen and Dominik Deffner from the Max Planck Institute for Evolutionary Anthropology and the Max Planck Institute for Human Development, respectively, studied the behaviour of great-tailed grackles, a bird species that has successfully invaded urban areas in North America. They found that the male grackles, who lead this charge, shy away from risk, a characteristic that is well-suited to chaotic environments like cities. These findings provide insight into how animals and humans can coexist successfully.
The research focused on analyzing the feeding behavior of grackles in urban environments. The researchers observed how quickly grackles learned where food was hidden and how quickly they relearned the location when it was swapped. They discovered that male grackles were more efficient foragers in uncertain environments, relearning the location of hidden food faster than females. The males exhibited risk-sensitive learning, sticking to feeding from a known location rather than exploring new ones, which the researchers inferred from their feeding behavior.
The differences in learning strategies between male and female grackles make biological sense, as males are the ones who disperse and lead their species’ urban invasion. The caution exhibited by male grackles when foraging in new territories helps them navigate the challenges of unpredictable urban environments. The researchers suggested that female grackles may learn from the already established males to overcome these challenges in later-arriving populations. The study highlights how risk-sensitive learners like male grackles are better adapted to cope in chaotic settings, such as human-induced urban environments.
Using computer simulations, the researchers examined the learning strategies that are most successful in unpredictable environments, such as urban settings. They found that risk-sensitive learners were more likely to dominate in such environments, indicating that this learning strategy is advantageous for animals navigating human-dominated environments. The study provides evidence of how grackles are thriving in urban environments and links the differences in foraging behavior between male and female grackles to their roles in leading the species’ invasion.
In order to facilitate future studies on human-animal coexistence, the researchers created an online repository where scientists and the public can access their custom-built modeling tools. By making their research tools openly available, the researchers aim to support further investigation into how animals adapt and thrive in human-dominated environments. The study emphasizes the importance of risk-sensitive learning strategies for animals navigating unpredictable urban environments and sheds light on how animals can successfully coexist with humans in the Anthropocene.
