This is read by an automated voice. Please report any issues or inconsistencies here. PORTLAND, Maine — Sharks are the most feared predators in the sea, and their survival hinges on fearsome teeth ...

For most of modern history, the open ocean has been treated as a place apart. Beyond the 200-nautical-mile limits of national jurisdiction, it was governed by custom, fragmented rules, and the ...

Sharks are the most feared predators in the sea, and their survival hinges on fearsome teeth that regrow throughout their lives. But changes in the ocean's chemistry could put those weapons at risk.

Teeth from a blacktip reef shark, seen in Germany. PORTLAND, Maine — Sharks are the most feared predators in the sea, and their survival hinges on fearsome teeth that regrow throughout their lives.

In this undated handout photo provided by Heinrich Heine University Duesseldorf in January 2026, a blacktip reef shark swims at Sealife Oberhausen in Oberhausen, Germany. (Maximilian Baum/Heinrich ...