What period is known as the "middle life" in Earth's history, characterized by the rise of mammals and dinosaurs?

The Mesozoic Era, often referred to as the "middle life," spans from approximately 252 to 66 million years ago. This era is significant as it is marked by the dominance of dinosaurs and the emergence of mammals. During this time, the Earth’s climate and geography underwent dramatic changes, creating diverse environments that allowed for the evolution of various species. The Mesozoic Era is further divided into three periods: the Triassic, Jurassic, and Cretaceous, each showcasing different stages in the evolution of life on land and in the oceans. This era concludes with a mass extinction event that paved the way for the subsequent rise of mammals in the later Cenozoic Era.

The other choices represent different geological times. The Paleozoic Era preceded the Mesozoic and featured the development of early life forms such as fish and amphibians. The Cenozoic Era follows the Mesozoic, characterized by the evolution and diversification of mammals and birds following the extinction of the dinosaurs. The Precambrian Era, which is even older, encompasses the time before the complex life forms that would dominate the later eras. Thus, the Mesozoic Era is accurately identified as the "middle life" due to its