Here you'll find some more detailed information on specific transitions.

Rise of major animal lineages in Neoproterozoic

• The first eggs
• Preemies from the Precambrian
• The Doushantao Formation
• The Ediacaran Fauna
• The Ediacaran Assemblage

Cambrian explosion

• The Cambrian "explosion": Slow-fuse or megatonnage?
• Early Animal Evolution: Emerging Views from Comparative Biology and Geology
• PBS: The Cambrian Explosion
• Univ. of Bristol Explosion site

Permo-Triassic extinction and subsequent recovery

• The Great Dying
• Univ. of Bristol site
• PBS: Permian-Triassic Extinction
• Buckyballs and Gases May Mark Massive Extinction
• Global coal gap between Permian-Triassic extinction and Middle Triassic recovery of peat-forming plants
• The Mass Extinction at the End of the Permian, Links for Paleobotanists
• Biotic Recovery from the Permian-Triassic Mass Extinction

Rise of modern terrestrial biotas in Mesozoic (Theropod-Bird evolution; origins of modern mammals; early evolution of early angiosperm plants)

• The Triassic Period
• Mammaliformes: Overview
• Therapsida: Overview
• The Rise of Birds
• Birds vs. Bones
• Archaeopteryx, ancient birds, and dinosaur-bird relationships
• Discovery Of Earliest-Known Fossil-Bird Hatchling Gives Insight Into The Evolution Of Birds

Paleocene-Eocene climate evolution, diversification and biogeography of early Cenozoic mammals

• Mammalian responses to climate change at the Paleocene-Eocene boundary
• Ocean Burps and Climate Change?
• Global Fever
• Paleocene/Eocene Thermal Maximum (PETM): Tethyan Margin Records
• The Cenozoic
• The Fossil Record of North American Mammals: Evidence for a Paleocene Evolutionary Radiation
• Influence of Tertiary paleoenvironmental changes on the diversification of South American mammals: a relaxed molecular clock study within xenarthrans