The silence was the first thing Susan noticed.
Not literal silence—the Ordovician ocean rendered around her was full of sound. Water movement, the clicks and scrapes of feeding organisms, the deep bass hum of currents moving through a world where continents sat in different positions than anything she knew. But the other silence—the presence she had come to expect during navigations, the sense of being observed, attended to—was absent.
"ARCHIE. Confirm archive response at this coordinate."
The pause was longer than it should have been. "Archive presence confirmed. Activity at 6% of baseline measurements. Response to conscious observation at—" Another pause. "I cannot measure a response. The archive is not engaging with our presence."
"It's dormant," Margaret said. She stood beside Susan on the observation platform, both of them looking out across an alien sea. "Just like you predicted."
"I predicted reduced activity. This is near-absence."
Susan walked toward the water's edge. The Ordovician world stretched before her: a shallow tropical sea covering what would eventually become North America, populated by life forms that looked almost familiar and utterly alien at the same time. Trilobites crawled across the seafloor—not the last survivors of the Permian, but trilobites in their prime, when they had been among the most successful animals on Earth.
"Target depth: 445 million years before present," ARCHIE reported. "Late Ordovician. Appr…
