In the Cretaceous Period started when the Jurassic period ended, which was exactly 144 million years ago and was also longer than any other period, reaching to approximately 65 million years. The Cretaceous period also marks the end of the Dinosaurs, who were destroyed by the meteorite that struck the earth 65 million years ago.
In the Cretaceous Period there was a newly discovered bird or glider called, The Microraptor Gui or also known as The Dinosaur with Four Wings, which was believed to show how birds evolved from a group of small dinosaurs called dromaeosaurs. The Microraptor gui was discovered in the Jiufotang Formation in western Liaoning, China. The Microraptor Gui is 77 cm in length and has four wings. What’s different about this species is that it has a wing on each of its hind limbs.
On January 23 in the issue of the journal Nature, Xu Xing, a paleontologist at the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing, China, says that in the the species was an early ancestor of birds that most likely used its feathered limbs, along with its long feather-fringed tail, to soar from tree to tree.
The dominant life in the Cretaceous Period was the dinosaurs they also branched out in to previously less-dominant species like horned dinosaurs. There were also insects, birds, and even mammals although they were the smallest animal life at the time period.
The early Cretaceous Period is where plant life, also known as Angiosperms, first began to blossom, this caused a growth in insects populations. The climate was the coldest for the Mesozoic times as glaciers appeared at the poles. Due to the steady increase of CO2 levels the cooler weather was gone and a warming period replaced it.
Morris, J. E. "The Cretaceous Period Home Page." Eons and Epochs Home Page. Web. 30 Aug. 2011.