The only constant is change. The Earth is continually changing and new environments replace older ones.  All forms of life change through natural mutations. This process is known evolutionary radiation. Some of the mutations result in characteristics that permit a species to survive in a new environment. Others lack it, so they perish. It is well demonstrated by the fact that no terrestrial vertebrate is known to have lived for more than two million years.
     Around 324 million years ago some sauropsids (early reptiles) developed unique characteristics, ones found in modern day mammals. Paleontologists often describe them as “more dog than frog.” They were the first synapsids. Taking advantage of an abundance of new food sources, they radiated into many different forms. They were the dominate terrestrial vertebrates for the next forty million years. Then, they were all but wiped out by the Permian Extinction Event, 251 million years ago. Their ecological niche was filled by the sauropsids, as they radiated into the dinosaurs and a great many other animals. They ruled the Earth until falling victim to the Cretaceous Extinction Event, 65 million years ago. They became extinct. The tables had turned and the few surviving synapsids quickly radiated into modern day mammals.
   This multi-faceted poster provides a comprehensive overview of the synapsids. It introduces each of the groups and shows many species, each accompanied by an informative caption. Few animals have radiated so quickly into so many different forms. Taking advantage of that, this poster also presents the synapsids as a classic example of evolutionary radiation, which is carefully explained. It also shows how the first tetrapods radiated into the synapsids and how the synapsids later radiated into mammals. Thus it is also a comprehensive prehistory of the mammals. This unique and totally original presentation of interrelated information has never before been presented in any media.