Tectonic activity continued to lift the landscape through the Ice Ages and by 1 million years ago, the Santa Ana Mountains had begun to form. Mammoths, Mastodonts, and Saber-Toothed Cats roamed the savannas and stream channels of Saddleback Valley. Their teeth and bone fossils were found during the construction of Costeau Park and the Community Center.
The Community Center murals illustrate the prehistory of the City of Laguna Hills changing landscapes. These are represented by a shallow tropical embayment, an open sea, and Ice Age grasslands. The remains of the diverse life that inhabited these paleo-environments are displayed throughout the foyer for public enjoyment and education.