On July 10, 2026, researchers from the Georgia Institute of Technology and BioFrontiers Institute at the University of Colorado Boulder proposed a new explanation for the formation of terracettes, the hillside steps that have puzzled scientists for over a century. Their study, published in the Journal of the Royal Society Interface, suggests that the movement of grazing animals could create these distinct landscape features.
Understanding Terracettes and Their Formation
Terracettes are periodic landscape patterns characterized by step-like formations along hillslopes. Each terracette comprises a flat tread and a sloped riser, with adjacent steps interconnected by shorter ramps. These formations are found worldwide, particularly on steep hillsides and mountainsides.
Historically, two hypotheses have been proposed regarding their formation: one suggests slow downhill movement of soil and rock, while the other attributes it to the trampling of grazing animals. The researchers aimed to determine the validity of these theories through a simulation of animal movements.
Simulating Grazing Animal Movements
The team utilized computational models to simulate how animals move across hilly terrains. They discovered that simple behaviors, such as seeking food while minimizing energy expenditure, could lead to the creation of terracettes. Lead author Benjamin Seleb noted, "I suspected the numerous grazing cows had something to do with it... I learned about the contested origins of these terracettes."
By modeling animal movement, the researchers found that when animals graze, they tend to walk horizontally across steep slopes, which packs the soil down and contributes to the formation of these landscape patterns.
Darwin's Historical Interest in Terracettes
Interestingly, the question of terracette formation intrigued renowned naturalist Charles Darwin over a century ago. In his 1881 book, The Formation of Vegetable Mould, through the Action of Worms, with Observations on their Habits, Darwin commented on the horizontal ledges formed by grazing animals. He noted that while animals likely contribute to their formation, other factors may also play a role.
Seleb and his colleagues revisited Darwin's observations, confirming that terracettes can be produced by grazing animals' movements. Saad Bhamla, another researcher, mentioned, "We spent a fair bit of simulations confirming something Darwin was already puzzling about nearly 150 years ago."
Conclusion: A New Understanding of Landscape Patterns
This study sheds new light on the longstanding mystery of terracettes, highlighting the impact of animal behavior on landscape formation. As researchers continue to explore these patterns, they provide valuable insights into the interactions between wildlife and their environments.
🤖 This article was rewritten by Feed and Figures' editorial AI from a report originally published by Phys.org. Facts and quotes are preserved from the original; the rewrite focuses on clarity and structure. For the unedited original, see the source link below.
