A sweeping global study warns that forests are becoming dominated by fast-growing trees, while slow-growing species that stabilize ecosystems are fading away. This shift could leave forests less diverse, less resilient, and less capable of protecting the planet from climate change. Credit: Shutterstock Trees are essential to life on Earth. They absorb and store CO 2 , support animals, fungi, and insects, hold soil in place, manage water cycles, and provide people with vital resources such as