The Jurassic Period is a geological time frame that lasted from about 201 to 145 million years ago. It is known for the rise of large dinosaurs, such as Brachiosaurus and Stegosaurus, which dominated the land. This period also saw the development of early birds and the first mammals, alongside a diverse range of plant life, including ferns and cycads. During the Jurassic Period, the Earth's continents were arranged differently than today, forming a supercontinent called Pangaea. As it began to break apart, new oceans and seas emerged, creating various habitats. The climate was generally warm and humid, supporting lush vegetation and a rich ecosystem.