This is a collection of 15 essays authored by Dr. Aldemaro Romero Jr. and his collaborators on paleontology and evolutionary biology. This volume encompasses the most critical papers Dr. Romero has written on biological evolution, from fossils to cave fauna. Among the fossils described are impressions of horseshoe crabs, jellyfishes, and the enigmatic paleocyphonautes. The latter represents a new understanding of the evolution of invertebrates by...