The article explores how changes in the environment can lead to mass extinctions of species throughout Earth's history. By studying the chemical makeup of rocks from different time periods, scientists can uncover clues about what caused these catastrophic events. The researchers focus on five major extinction events and analyze the geochemical data to understand the environmental impacts that led to the loss of biodiversity. This approach helps us piece together the puzzle of how past mass extinctions were triggered and what consequences they had on life on Earth.