This book investigates the phenomenon of evolutionary stasis, exploring why certain ancient species have persisted virtually unchanged through vast geological timescales while others have gone extinct or undergone significant adaptation. Peter Douglas Ward, a paleontologist and evolutionary biologist, draws upon extensive fossil records and biological research to present a compelling argument about the factors that allow some life forms to survive millennia. The work examines the interplay of environmental stability, genetic resilience, and ecological niche in maintaining these 'living fossils'.

This work is recognized for its in-depth exploration of evolutionary stasis and the concept of 'living fossils.' Ward's analysis is grounded in paleontological evidence, offering a detailed look at species that have defied evolutionary pressures. The book provides a comprehensive overview of the scientific understanding of why some ancient life forms persist while others vanish.