The Cambrian ocean was wrong.
Susan knew it the moment ARCHIE rendered the environment—before she could identify what specifically triggered the wrongness, her body reacted. Nausea. Disorientation. The particular vertigo of perceiving something that refused to resolve into coherent experience.
"ARCHIE. Confirm rendering stability."
"Rendering is stable, Dr. Harris. The distortion you perceive is not an artifact. It is the environment itself."
They stood on their observation platforms in a shallow sea 538 million years old. The Cambrian explosion—the sudden diversification of complex life that had puzzled biologists for a century. Susan had expected strangeness. She had not expected this.
The water was water. The seafloor was sediment. The organisms swimming through the rendered environment were recognizable—trilobites in their earliest forms, anomalocaridids hunting with grasping appendages, the bizarre body plans of the Burgess Shale fauna. All of it should have made sense.
But the light was wrong.
"I see it too," Margaret said. The crystallographer had gone pale. "The angles. Look at how it bends."
Sunlight filtering through the ancient ocean followed paths that didn't match any optics Susan understood. It bent around organisms, pooled in spaces where nothing should have obstructed it, cast shadows that pointed in directions contradicting the source.
"Light works however the manifold dictates," Susan heard herself say. "The substrat…
